Zero Trust on Azure

Your network can be hardened end to end and still sit one compromised account away from a breach. That sentence is the whole case for Zero Trust, and it explains why the generic Zero Trust architecture picture keeps circulating. Users and devices at the top, an identity provider, MFA, a policy engine, a policy enforcement point, segmentation, protected resources, and a monitoring column on the side. Never trust, always verify, least privilege. This post is about Zero Trust on Azure: which Microsoft service does each job, and where the neat boxes stop matching how the platform behaves.

I like the generic picture. It is the NIST SP 800-207 model with icons, and it summarizes a modern access path fairly. It does not tell you what to switch on in an Azure tenant, though. So I redrew it with Azure icons, one service per box, and wrote down what I had to change to make it accurate.

Zero Trust on Azure: the generic architecture mapped to Microsoft Entra, Intune, Global Secure Access, Azure networking, and Microsoft Sentinel.

Zero Trust on Azure: the same spine, with names on it

The generic flow has eleven steps. Here is what each one is called in a Microsoft tenant.

Steps 1 to 6: identity and policy

  1. Verify users. Employees, admins, vendors and workloads are all Microsoft Entra ID identities. Vendors come in through External ID (B2B), and workloads through app registrations and managed identities. That last group matters more than the picture suggests, and I will come back to it.
  2. Check devices. Device trust is an Intune compliance policy plus a Defender for Endpoint risk score, which Entra receives as a device claim. Patch status, encryption, OS health and firewall state are compliance checks, not network checks.
  3. Verify identity. One identity provider: Entra ID. In a hybrid tenant, Connect Sync or Cloud Sync brings in the on-premises accounts, and the Active Directory authority boundary stays where it was.
  4. Strengthen authentication. MFA, authentication strengths, passkeys and FIDO2 are Entra features. The policy that demands them lives in the next box.
  5. Evaluate access. Conditional Access takes the signals: user, group, device compliance, location, sign-in risk and user risk, client app, and the sensitivity of the target app.
  6. Make policy decisions. Also, Conditional Access. Grant, block, require MFA, require a compliant device, require an authentication strength, or apply session controls.

Steps 7 to 11: enforcement, isolation and visibility

  1. Enforce access. This is where the picture and the platform part ways. More below. The candidates are Global Secure Access, Front Door and Application Gateway with WAF, API Management validate-jwt, the application itself, and Bastion.
  2. Isolate workloads. Virtual networks, network security groups, application security groups, Azure Firewall, private endpoints, and private DNS.
  3. Protect resources. App Service, Functions, API Management, Azure SQL, Storage, Key Vault, and for the Active Directory box, Entra Domain Services or domain controllers behind Entra Private Access.
  4. Monitor continuously. Microsoft Sentinel for SIEM and SOAR, Defender for Cloud for posture and workload protection, ID Protection for risky sign-ins and users, Log Analytics for everything the rest emits.
  5. Build the foundation. Key Vault and customer managed keys, Purview labels and DLP, managed identities, Azure Policy, PIM, backup, and a landing zone you segment before the first workload lands.

That mapping is useful on its own. Architecture reviews ask me for it regularly, usually from someone with the generic picture, asking, “so what do we actually buy?” But three of the boxes hide something, and that’s why I’m writing this post.

Policy engine and policy administrator share one box

NIST 800-207 separates the policy engine (decides) from the policy administrator (tells the enforcement point what it decided). The generic picture keeps them apart and gives the administrator its own job list: create a secure session, issue an access token, enforce policy decisions, monitor the session, log and audit.

Zero Trust on Azure does not split them into two services. Conditional Access is Microsoft’s policy engine, and the token service that acts on its verdict is the same Entra ID. The decision and the administration happen in one evaluation at token issuance. There is no separate component you can point at and call the PA.

That collapse is convenient, and it has a cost. Because the decision binds to token issuance, the decision also binds to token lifetime. Which brings me to the enforcement point.

The enforcement point in Zero Trust on Azure is not one gateway

The picture draws a single Policy Enforcement Point, a ZTNA gateway or reverse proxy, and lists four jobs for it: verify every request, decrypt and inspect traffic, enforce least privilege, block unauthorized access.

On Azure, I count at least six places that do some of that for some traffic, and none of them does all of it for all traffic.

  • Entra ID itself, at token issuance. Conditional Access enforces here, and for most SaaS and Microsoft 365 traffic this is the only enforcement point there is.
  • Global Secure Access, the ZTNA layer. Private Access fronts internal apps and, since January 2026, domain controllers, so Kerberos traffic can finally sit behind a Conditional Access policy. Internet Access is the secure web gateway. TLS inspection for it is still in preview as I write this, so “decrypt and inspect traffic” is a roadmap item for part of the stack, not a given.
  • Front Door and Application Gateway, with WAF policies, for public web entry points.
  • API Management, where validate-jwt checks the token the app will later trust.
  • The application, which validates the token again and applies its own authorization. Microsoft’s own guidance says Conditional Access “doesn’t prevent the app from blocking access on its own”. The app is an enforcement point whether you designed it that way or not.
  • Bastion, for the administrative sessions that never pass through any of the above.

The generic picture is not wrong to draw one box. It is wrong if you read it as one product. Every Zero Trust review I have done ended with a table of enforcement points and the traffic each one does not see. The gaps in that table are the architecture.

“Verify every request” means “verify every token issuance”

This is the part I most wanted to write down, because it surprises people when they measure it.

Entra evaluates Conditional Access when it issues a token. Access tokens live 60 to 90 minutes by default. Between issuances, the resource trusts the token, and a policy change, a password reset, a disabled account, or a risk event does nothing to a token already in use. “Verify every request” at the resource means “check the signature and expiry of a token that Entra verified up to an hour and a half ago”.

Continuous Access Evaluation closes that gap, but only for resources and clients that support it. In my earlier post, Microsoft Entra ID under the hood, I measured this on a test tenant. A CAE-aware client received a 1439-minute token, and the resource rejected it four seconds after I revoked its sessions. The non-CAE client next to it kept a 65-minute token and kept receiving 200 responses until it expired. Same tenant, same policy, same user. The only difference was whether the client and resource spoke CAE.

So the “Revoke” decision in the picture’s policy engine box is real, but it depends on the plumbing. For your own APIs on App Service, Functions, or API Management, CAE does nothing unless you build the claims challenge handling yourself. The honest version of the diagram puts a footnote under Revoke, and that is what mine does.

Where this Zero Trust on Azure mapping is the wrong answer

  • If most of your estate is not on Azure. Conditional Access and Global Secure Access still apply to a mixed estate, but the segmentation and protected resources rows are Azure-specific. For AWS or on-premises workloads, Entra Private Access gives you an enforcement point in front of them, not segmentation behind them.
  • If you have no Intune. Device compliance is the second strongest signal Conditional Access has. Without a device management platform feeding it, “check devices” collapses to “is the device Entra joined”, a weaker test than the picture implies.
  • If you are on Entra ID Free or P1 only. Sign-in risk and user risk conditions need P2. Global Secure Access needs the Entra Suite or standalone licenses. The mapping above assumes you have them, and many tenants do not.
  • If your apps cannot validate tokens. Legacy applications behind an App Proxy or Private Access get an enforcement point in front of them and nothing inside them. That is still better than nothing, and it is not Zero Trust at the application layer.
  • If nobody reads Sentinel. The monitoring column feeds risk back into policy only if someone tunes analytics rules and acts on the incidents. A workspace that ingests everything and alerts no one is a cost, not a control.

The question at the bottom of the picture

The generic post ends with a good question: if an attacker compromised one employee’s account today, how much of your network could they reach?

On Azure, the answer comes from five smaller questions. Does the compromised identity hold standing privileged roles, or does PIM activate them with a window? Does Conditional Access require a compliant device, so a stolen credential on an unmanaged laptop stops at step five? Do the resources sit on private endpoints, behind network security groups that only admit the subnet that should talk to them? Do the workloads that matter speak CAE, so a revoke lands in seconds rather than at the next token expiry? And can Sentinel tell you any of this happened before the attacker finishes?

I have not yet met a tenant where all five answers were yes. The mapping in this post is how I find out which ones are no.

Zero Trust is not a product you install. Zero Trust on Azure is about fifteen services configured to agree with each other, and the diagram only becomes true once they do. If you want the same treatment for the identity layer alone, Microsoft Entra ID goes deeper under the hood, and the API Management for AI workloads series covers the validate-jwt enforcement point in detail.

Logic Apps Automation Pricing: The Free Grant and What It Changes

In July, I wrote a preview assessment of Logic Apps Automation. One row in my reality-check table read: “Pricing: not finalised.” I declined to quote meters, because third-party posts were running ahead of Microsoft.

That row is now closed. On October 7, the Logic Apps team announced pricing together with a monthly free grant. This post covers what the numbers say, and which parts of my July advice they confirm or correct.

One note on terms first. In July I described the hierarchy as Project, Application, Workflow. The documentation now says Environment, App, Workflow. I use the new names here.

What you get for free

Every Azure subscription receives the following:

ComponentFree grant
Managed environmentOne environment, free for the first 60 days only
Workflow runtime108,000 execution-seconds per month (about 30 hours)
Data retention1 GB per month
Managed connector calls1,000 Standard and 500 Enterprise per month
Knowledge storage1 GB per month
AI usage1,100 Azure Agent Credits (AACs) per month
Isolated code execution18,000 seconds per month (about 5 hours)

What you pay beyond it

The pricing documentation lists these rates for East US:

MeterRate
Managed environment$0.042 per hour
Workflow runtime$0.00008 per execution-second
Data retention$0.12 per GB per month
Standard connector action$0.000125
Enterprise connector action$0.001
Knowledge storage33 AACs per GB per month ($0.33)
Sandbox$0.000024 per vCPU-second, $0.000003 per GiB-second

The runtime meter counts execution-seconds on a baseline of 1 vCPU and 2 GiB of memory. Consumption, in contrast, counts actions. Standard charges for reserved capacity. As a result, a slow workflow now costs more than a fast one, regardless of its action count.

AI usage is billed in AACs, converted from tokens based on the model you select. In July, I called the agent iteration bound “your cost fuse”. That fuse now protects a number: 1,100 AACs per month. Moreover, if you bring your own model, Automation does not charge the token usage at all.

What happens on day 61

The environment fee is the part that matters most. At $0.042 per hour, an environment costs about $30.66 per month, whether or not anything runs.

Compare that with the grant. By my arithmetic, the monthly usage grants are worth roughly $21 at list rates: $8.64 of runtime, about $11 of AI usage, and under $2 for everything else. The AI figure assumes one AAC equals one cent, which I derive from the knowledge storage line. Microsoft does not state it.

So from day 61, the fixed fee exceeds the value of everything the grant gives you. The grant lowers the bill. It does not make the platform free.

One correction to my July post

My decision table placed “long idle periods with traffic spikes” on Automation, because the runtime scales from 0 to N. The compute still does. However, the environment fee does not scale to zero.

Therefore, I would now move very sporadic, low-volume work back to Consumption, which has no fixed fee. Automation remains the better fit for bursty AI and agent workloads that justify roughly $30 a month as a baseline.

The grant has an owner problem

My main concern in July was governance: who owns a workflow, and what happens when that person leaves. The grant adds a billing version of the same question.

The grant applies to the first environment you create in a subscription. Delete that environment and you lose the grant for good. A new environment does not restore it. In addition, existing preview users must create a new environment to receive it.

Consequently, the first person to click “create” decides where the subscription’s free grant lives. The documentation itself names “billing context” as a reason to separate environments. My July advice was a named owner and a named deputy. Apply the same rule here.

Where this is the wrong answer

Sustained load. Running the baseline continuously consumes about 2.6 million execution-seconds, or roughly $210 per month, plus the environment. A Logic Apps Standard WS1 plan costs about $175. So my July claim holds: predictable 24×7 load belongs on Standard.

EU data residency. The preview runs in Australia East, East Asia, North Central US, Southeast Asia, Sweden Central, UK South, and West US. West Europe and North Europe are missing. Inside the EU, Sweden Central is the only option.

Note: How my list compares with the announcement

RegionAnnouncement and docsMY portal
Australia East, East Asia, North Central US, Southeast Asia, UK South, West USYesYes
Sweden CentralYesNo
Brazil South, West Central USNoYes
Central US EUAP, East US 2 EUAPNoYes

Budgets that need certainty. The published rates are East US estimates, and East US is not a preview region. Furthermore, Microsoft says the new pricing rolls out in phases and may change before general availability.

Anyone counting on 30 free hours of production. The documentation states that the runtime host also runs during portal authoring. Designing in the portal draws on the same grant.

What stays open

Pricing closes one item. The others from July remain: CI/CD and environment-as-code, an audit read role, ownership transfer, a model support matrix, and a clear statement on VNet and private endpoints. Knowledge bases and sandboxes are still labelled preview, although the grant already covers both.

What I would do on Monday

My July advice to decision makers was: fund one team, one environment, one non-regulated workflow. That advice now costs close to nothing for 60 days. Three additions follow from the pricing.

First, create the free environment deliberately, in the subscription and region you intend to keep. Second, check the Free Grants tab under Settings weekly during the first month. Third, put day 61 in the calendar, and decide before that date whether the workload is worth $30 a month.

The technology is still further along than the operating model. Now the bill is, too.

When Agentic Workloads Break the PaaS Assumptions

This series started with a map and grew into seven pieces. Five layers came first: compute, where load shape picks the service; messaging and orchestration, where two questions replace four product choices; data patterns, where idempotency and the outbox keep a platform correct; governance and identity, where policy and audit become the compliance posture; and observability and FinOps, where behaviour and cost become visible. Then came the lens: from design to demonstrable operation, the shift from “is it built?” to “can we operate it responsibly?”

Every one of those pieces rests on a shared assumption. The system does what you told it to do. You wrote the workflow, you defined the routes, you set the policies, and the platform executes them. That assumption has held for every integration platform I’ve built. Agentic workloads break it. So this capstone asks what changes when the thing making decisions inside your platform is a model, not your code, and why each layer, plus the readiness lens itself, deserves a second look because of it.

The assumption agentic workloads break

Conventional integration is deterministic. A message arrives, a workflow runs its defined steps, a router sends it where the rules say. You can read the code and know what will happen. You can test every path. When something fails, you trace it to a step you wrote.

Agentic workloads replace part of that determinism with a model that decides at runtime. The agent reads context, picks a tool, interprets the result, and chooses the next action. Moreover, it does so differently depending on inputs you didn’t fully anticipate. That’s the point of it: the flexibility is the feature. But it means you can no longer read the code and know what will happen. So the ground under every layer shifts: behavior is no longer exactly what you specified.

None of this argues against agentic workloads. It argues for revisiting each layer with the shift named explicitly. Let’s do that.

Compute: the loop changes the shape of the work

The compute layer sorted workloads by load shape: steady request traffic to App Service, event-driven bursts to Functions or Container Apps. Agentic workloads add a shape that sorting didn’t account for: the loop.

An agent doesn’t process a request and return. It reasons, calls a tool, waits, observes, and reasons again, sometimes for many cycles, before it finishes. That’s neither a clean request-response nor a discrete event. Instead, it’s a long-running loop of unpredictable duration with external calls in the middle. So the compute question changes. You’re no longer asking “steady or bursty” alone. You’re asking how to host something that runs for seconds or minutes, holds state across tool calls, and scales on a dimension concurrent reasoning loops that CPU-and-memory autoscale captures poorly. Container Apps with event-driven scaling often fit better here than App Service, and the orchestration frequently belongs in a workflow engine rather than raw compute.

Messaging and orchestration: the agent is a non-deterministic router

The messaging layer drew a clean line. Deterministic routing rules sent messages where the logic dictated. An agent orchestrating tool calls is, in effect, a router too, but a non-deterministic one. It decides which tool to call from its reading of the context, not from a rule you wrote.

The reliability consequences are real. Delivery guarantees still matter; an agent that triggers a business action still needs that action to occur exactly once, so Service Bus and the idempotency store in the data layer remain as relevant as ever. What changes is predictability. You can’t fully anticipate which actions the agent will trigger, or in what order. Therefore, the orchestration has to stay correct under sequences you didn’t design for. One practical lesson from building these loops applies directly: agent outputs rarely arrive as the clean structures a deterministic step would emit, so you build explicit bridges between agent actions rather than assuming shape.

Data: state and correctness under non-determinism

The data patterns held a platform correct when systems it didn’t control misbehaved. Agentic workloads make those patterns more necessary, not less, and they add one more.

Idempotency matters more because an agent may retry a tool call or repeat an action as it reasons, so the dedup store carries a heavier load. The outbox matters just as much, because an agent-triggered write still has to propagate reliably. Workflow state matters more too, since the reasoning loop is exactly the kind of long-running, restart-surviving process that needs durable state and a correlation ID. And then the new one: conversation and context state. An agent carries context across turns, and that context has to live somewhere durable and queryable, which explains why a flexible document store keeps showing up as the default for agentic conversation state. The access pattern points at the store. Same principle as the map, applied to a new kind of state.

Governance and identity: where the assumptions break hardest

This layer changes most, and I’d insist any integration architect think it through before shipping an agentic workload.

The governance layer secured a deterministic platform. Identity answered who the caller was; policy constrained what the platform could be. Both still matter. However, agentic workloads open a gap that neither fully closes. Identity secures who the agent is. It does not touch what a poisoned tool result or a manipulated retrieved document makes the agent do. Prompt injection rides in through the data the agent requested inside the reasoning loop, downstream of the perimeter check everyone assumes protects them.

So the governance layer needs additions a deterministic platform never required:

  • Authorization moves per-action: A validated identity at the edge isn’t enough. Each tool call the agent makes needs its own check: is this specific action allowed for this tenant right now? The perimeter check happens once; the risk recurs on every call inside the loop.
  • Recovery means compensation, not retry: Agent actions have side effects across systems. A failed sequence three actions deep can’t restart from the top; it needs compensating actions to undo what already happened. That’s saga-style thinking, and you design it; it doesn’t emerge.
  • Containment has to be possible: When an agent misbehaves, you stop it fast, and at more than one layer. Layered containment, from a single configuration flip-up to a full block, turns “contain the agent” from an incident-call debate into a seconds-long operation.
  • Evaluation becomes a first-class layer: Operational observability tells you the agent is running. It doesn’t tell you the agent’s outputs are quietly degrading. Under the EU AI Act’s oversight and transparency duties, that stops being optional polish and becomes evidence you’re meeting an obligation.

The readiness lens, asked again

The design-to-operation post posed the question that decides go-live: not “is it built?” but “can we operate it safely, recoverably, auditably, and predictably?” Agentic workloads sharpen every word of that sentence.

Safely now includes per-action authorization and containment, because the threat walks in as data. Recoverably now means compensation and sagas, because retry alone can’t undo side effects. Auditably now covers what the agent accessed, which tool it called, why it acted, and what policy constrained it evidence the EU AI Act increasingly expects. And predictably is precisely the property the agent gave up, which is why the surrounding architecture has to supply it instead. The production baseline, the demonstrable-versus-designed test, the three moments of readiness all of it still applies. Each bar sits higher.

The revised framework

The map closes with five questions. For agentic workloads, they hold, and each gains a harder edge. Before an agentic workload goes near a real system, I’d add these:

Can I host a long-running reasoning loop, not just a request or an event? Can my orchestration stay correct when I can’t predict the action sequence? Does my data layer hold conversation state as well as business state, with idempotency doing heavier duty? Is authorisation per-action, not just per-identity? Can I contain a misbehaving agent in seconds? And can I evidence what the agent did, why, and whether its quality held?

Those aren’t different questions from the series. They’re the same layers, asked again under non-determinism, and then held up against the readiness lens one more time.

The shape of it

Agentic workloads don’t replace the Azure PaaS foundation an integration architect builds on. They stress it. Every layer in this series still includes compute, messaging, data, governance, and observability, but each one now supports a workload that decides for itself at runtime. The compute layer meets the loop. The messaging layer meets a non-deterministic router. The data layer meets conversation state and heavier idempotency. The governance layer meets a threat that walks in through the front door as data. And the readiness lens meets a workload that surrendered predictability, so the architecture has to supply it.

The through-line of the whole series holds here too. The model is the least differentiated part of a production agent. What separates a demo from something you can run against real systems in a regulated industry is the architecture around it: the same layers, asked harder, and proven in operation rather than promised in design. So the foundation was never wasted. It’s exactly what agentic workloads need, applied with the assumptions made explicit.

That’s the series. Start at the Azure PaaS map for the layer-by-layer foundation, take the design-to-operation lens with you as the test, and come back here for what changes when the workload thinks for itself.

AI Foundry Spoke Model Deployment: Why It Still Happens

A comment on the first post in this series asked why AI Foundry Spoke model deployment happens at all in the Citadel pattern, a question worth answering properly in its own post rather than buried in a reply thread.

Great article as usual! Just wondering, in the given Governance Hub & Agent Spoke architecture, what is the purpose of deploying the models both to the Spoke and the Hub? Shouldn’t they only be deployed to the Hub and provided from there?

That’s a sharp question, and it points at a real tension in the Citadel pattern that the original post didn’t call out explicitly enough. Here’s the direct answer, followed by the reasoning behind it.

The short answer

No, they shouldn’t both serve your application’s inference needs. Only the Hub deployment should. The model deployment sitting in the Spoke exists today because of how Azure AI Foundry’s Agent Service currently works, not because the architecture intends a second, governance-free inference path.

That distinction matters, so it’s worth walking through why the Spoke deployment is there at all.

Why AI Foundry Spoke Model Deployment Happens at All

In the ideal version of the Citadel pattern, every model call flows through the Hub’s APIM gateway. That’s the entire point of centralizing governance in one place. It’s what the rest of the series demonstrated: every agent call routed through apim-wpvlimv4ngkns, with token tracking, content safety, cost attribution, and the kill switch all enforced at that single choke point.

The Spoke still ends up with its own local model deployment because the AI Foundry Agent Service needs one for two reasons. This is a direct consequence of how the AI Landing Zone Bicep templates provision the Spoke, not a choice made anywhere in this series.

It powers the Agent Service’s own internal capabilities. Thread management, agent orchestration, and built-in tools like Code Interpreter or File Search (when enabled) call the model directly, through Foundry’s own runtime, rather than through any external endpoint you control. That runtime doesn’t route through APIM. It talks to whatever model deployment sits alongside it in the same project.

It satisfies the Foundry project’s provisioning requirements. A Foundry project currently expects an associated model deployment to exist as part of setting up the project, even if your actual application traffic never calls that deployment directly.

Neither of these is a governance decision. They’re artifacts of how the Agent Service is architected right now.

Two paths, not one

The practical result is that a Citadel deployment ends up with two separate paths to a model, and they serve different purposes.

The Spoke’s local deployment exists for Foundry’s own internal agent runtime. It’s not meant to see your production traffic, and if it does, none of the governance you built in the Hub applies to those calls.

The Hub’s deployment, reached through APIM, is what your application code should use. That’s what we wired up explicitly in Part 2 of this series, with the standard OpenAI SDK pointed at the gateway rather than directly at the Foundry endpoint. The Hub itself is built on the AI Hub Gateway Solution Accelerator, and its AI gateway capabilities are exactly what give APIM the token metering, content safety, and audit trail features this series has leaned on throughout.

The second path exists precisely because of a limitation the series already documented. The Agent Service SDK, in its current preview state, doesn’t route its own LLM calls through APIM. It bypasses the gateway entirely, which means using it directly would mean giving up token metering, policy enforcement, and audit trails on every call the agent makes. That’s why Part 2 used the standard OpenAI SDK pointed at APIM instead of the native Agent Service SDK, and it’s the same underlying issue this reader’s question is really about.

What this means in practice

If you’re building on this pattern today, treat the Spoke’s model deployment as infrastructure the platform needs to exist, not as a second inference endpoint your application is allowed to call. Point your application code at the Hub, through APIM, every time. Leave the Spoke deployment alone to do the job Foundry needs it for internally, and don’t build anything that calls it directly for your own traffic.

If you’re reviewing someone else’s Citadel-pattern deployment, this is worth checking explicitly. A model deployment sitting in a Spoke isn’t wrong by itself, but it’s worth confirming nothing in the application is quietly calling it and skipping the gateway.

Where this is heading

I’d expect this to tighten up as the Agent Service SDK matures out of preview and gains native APIM routing support. When that happens, the two-path situation described here becomes a one-path situation, and the Spoke deployment stops being something you need to actively route around.

Until then, the answer to the original question stands: deploy to the Hub, govern everything through APIM, and treat the Spoke’s model deployment as plumbing the platform needs rather than a second front door.

Thanks to the reader who asked the original question. It’s exactly the kind of detail that’s easy to leave implicit in an architecture diagram and much more useful said out loud.

Microsoft Foundry Citadel Platform Azure: Conversation Persistence with Cosmos DB

In the previous post, we connected a real tool-calling agent to the Microsoft Foundry Citadel Platform on Azure, routing every LLM call through the APIM governance hub in Sweden Central. The agent answered weather questions; the hub captured usage events in Cosmos DB; and Application Insights confirmed that both LLM calls were governed. The agent worked, but it had no memory. Every run started fresh, with no record of what was asked or answered.

This post adds conversation persistence to the Microsoft Foundry Citadel Platform on Azure. Every agent run now produces a structured document in the spoke’s Cosmos DB conversations container: the user’s question, the tool call made, the tool result, the agent’s answer, token counts, model version, and timestamp. The agent gains a memory layer, marking the transition as the spoke’s data tier becomes active.

What We Build

Each agent run writes one document to the spoke Cosmos DB:

{
"id": "run-20260625-143022-stockholm",
"principal_id": "steefjan@msn.com",
"timestamp": "2026-06-25T14:30:22.441Z",
"question": "What is the weather like in Stockholm right now?",
"tool_calls": [
{
"name": "get_weather",
"arguments": {"location": "Stockholm"},
"result": {
"location": "Stockholm, Sweden",
"temperature_celsius": 22.5,
"wind_speed_kmh": 7.2,
"condition": "Overcast"
}
}
],
"answer": "The weather in Stockholm is overcast with a temperature of 22.5°C...",
"model": "gpt-4o-2024-11-20",
"prompt_tokens": 234,
"completion_tokens": 67,
"total_tokens": 301,
"apim_gateway": "apim-wpvlimv4ngkns.azure-api.net"
}

The partition key is /principal_id matching the container definition deployed by the spoke Bicep template. In addition, this arrangement ensures that all conversations for a given user are grouped into the same logical partition, making per-user history queries efficient.

The agent writes the document after completing the run, so a failed or incomplete run leaves no record.Moreover, it’s clean, simple, and auditable.

Prerequisites

From the previous two posts you should have:

  • Hub deployed in rg-ai-hub-gateway-dev
  • Spoke deployed in rg-ai-spoke-dev with Cosmos DB cosmos-tggi2gmkw22w4, database cosmos-dbtggi2gmkw22w4, container conversations
  • App Config appcs-tggi2gmkw22w4 populated with COSMOS_DB_ENDPOINT and CONVERSATIONS_DATABASE_CONTAINER
  • agent.py, config.py, and tools.py from the previous post
  • Virtual environment activated with openai, azure-appconfiguration, azure-identity, and requests installed

Step 1 — Install the Cosmos DB SDK

With your virtual environment activated:

pip install azure-cosmos

Pitfall: Cosmos DB Public Network Access

If your Cosmos DB has firewall rules enabled (which the spoke Bicep template sets by default), your local IP needs to be in the allowed list or public access needs to be set to All networks for dev. Check via the portal: cosmos-tggi2gmkw22w4 (your instance) → Networking → Public access → All networks → Save. In production this would be networkIsolation=true with private endpoints only.

Step 2 — Extend Config to Read Cosmos DB Settings

The spoke App Config already contains COSMOS_DB_ENDPOINT and CONVERSATIONS_DATABASE_CONTAINER — populated automatically during deployment. Extend config.py to pull these:

$lines = @(
"from azure.appconfiguration import AzureAppConfigurationClient",
"from azure.identity import DefaultAzureCredential",
"",
"APP_CONFIG_ENDPOINT = 'https://appcs-tggi2gmkw22w4.azconfig.io'",
"LABEL = 'ai-lz'",
"",
"def get_config() -> dict:",
" credential = DefaultAzureCredential()",
" client = AzureAppConfigurationClient(",
" base_url=APP_CONFIG_ENDPOINT,",
" credential=credential",
" )",
" keys = [",
" 'AI_FOUNDRY_PROJECT_ENDPOINT',",
" 'CHAT_DEPLOYMENT_NAME',",
" 'APIM_GATEWAY_URL',",
" 'APIM_SUBSCRIPTION_KEY',",
" 'COSMOS_DB_ENDPOINT',",
" 'CONVERSATIONS_DATABASE_CONTAINER',",
" 'DATABASE_NAME',",
" ]",
" config = {}",
" for key in keys:",
" setting = client.get_configuration_setting(key=key, label=LABEL)",
" config[key] = setting.value",
" return config",
"",
"if __name__ == '__main__':",
" cfg = get_config()",
" for k, v in cfg.items():",
" print(f'{k}: {v[:40]}...')"
)
[System.IO.File]::WriteAllLines("$PWD\config.py", $lines, [System.Text.UTF8Encoding]::new($false))

Test it:

python config.py

You should now see seven keys including COSMOS_DB_ENDPOINT pointing to https://cosmos-tggi2gmkw22w4.documents.azure.com:443/ and CONVERSATIONS_DATABASE_CONTAINER set to conversations.

Step 3 — Create cosmos.py

Create a dedicated Cosmos DB module:

$code = 'import os
cosmos = """from azure.cosmos import CosmosClient
from azure.identity import DefaultAzureCredential
import uuid
from datetime import datetime, timezone
def get_cosmos_client(endpoint):
return CosmosClient(url=endpoint, credential=DefaultAzureCredential())
def save_conversation(endpoint, database_name, container_name, principal_id, question, tool_calls, answer, model, prompt_tokens, completion_tokens, total_tokens, apim_gateway):
container = get_cosmos_client(endpoint).get_database_client(database_name).get_container_client(container_name)
now = datetime.now(timezone.utc)
fmt = \"%Y%m%d-%H%M%S\"
doc_id = f\"run-{now.strftime(fmt)}-{str(uuid.uuid4())[:8]}\"
document = {\"id\": doc_id, \"principal_id\": principal_id, \"timestamp\": now.isoformat(), \"question\": question, \"tool_calls\": tool_calls, \"answer\": answer, \"model\": model, \"prompt_tokens\": prompt_tokens, \"completion_tokens\": completion_tokens, \"total_tokens\": total_tokens, \"apim_gateway\": apim_gateway}
container.create_item(body=document)
print(f\"Saved conversation: {doc_id}\")
return document
def get_conversation_history(endpoint, database_name, container_name, principal_id, limit=5):
container = get_cosmos_client(endpoint).get_database_client(database_name).get_container_client(container_name)
query = f\"SELECT TOP {limit} c.id, c.timestamp, c.question, c.answer, c.total_tokens FROM c WHERE c.principal_id = @principal_id ORDER BY c._ts DESC\"
return list(container.query_items(query=query, parameters=[{\"name\": \"@principal_id\", \"value\": principal_id}], partition_key=principal_id))
"""
agent = """import json
from openai import AzureOpenAI
from config import get_config
from tools import get_weather, WEATHER_TOOL_DEFINITION
from cosmos import save_conversation, get_conversation_history
PRINCIPAL_ID = \"steefjan@msn.com\"
def run_agent_with_memory(user_question):
cfg = get_config()
apim_base = cfg[\"APIM_GATEWAY_URL\"].rstrip(\"/\").replace(\"/openai\", \"\")
client = AzureOpenAI(azure_endpoint=apim_base, api_key=cfg[\"APIM_SUBSCRIPTION_KEY\"], api_version=\"2024-02-01\")
messages = [{\"role\": \"user\", \"content\": user_question}]
print(f\"Sending request via APIM: {apim_base}\")
response = client.chat.completions.create(model=cfg[\"CHAT_DEPLOYMENT_NAME\"], messages=messages, tools=[WEATHER_TOOL_DEFINITION], tool_choice=\"auto\")
msg = response.choices[0].message
messages.append(msg)
tool_calls_log = []
answer = msg.content or \"\"
total_prompt = response.usage.prompt_tokens
total_completion = response.usage.completion_tokens
if msg.tool_calls:
for tool_call in msg.tool_calls:
args = json.loads(tool_call.function.arguments)
print(f\" -> Tool call: get_weather({args})\")
result_str = get_weather(**args)
result_json = json.loads(result_str)
print(f\" -> Tool result: {result_str}\")
tool_calls_log.append({\"name\": tool_call.function.name, \"arguments\": args, \"result\": result_json})
messages.append({\"role\": \"tool\", \"tool_call_id\": tool_call.id, \"content\": result_str})
response2 = client.chat.completions.create(model=cfg[\"CHAT_DEPLOYMENT_NAME\"], messages=messages)
answer = response2.choices[0].message.content
total_prompt += response2.usage.prompt_tokens
total_completion += response2.usage.completion_tokens
save_conversation(endpoint=cfg[\"COSMOS_DB_ENDPOINT\"], database_name=cfg[\"DATABASE_NAME\"], container_name=cfg[\"CONVERSATIONS_DATABASE_CONTAINER\"], principal_id=PRINCIPAL_ID, question=user_question, tool_calls=tool_calls_log, answer=answer, model=cfg[\"CHAT_DEPLOYMENT_NAME\"], prompt_tokens=total_prompt, completion_tokens=total_completion, total_tokens=total_prompt+total_completion, apim_gateway=apim_base.replace(\"https://\", \"\"))
return answer
if __name__ == \"__main__\":
cfg = get_config()
print(\"=== Recent conversation history ===\")
history = get_conversation_history(cfg[\"COSMOS_DB_ENDPOINT\"], cfg[\"DATABASE_NAME\"], cfg[\"CONVERSATIONS_DATABASE_CONTAINER\"], PRINCIPAL_ID, 3)
if history:
for h in history:
print(f\" [{h[\"timestamp\"]}] Q: {h[\"question\"][:60]}...\")
else:
print(\" No previous conversations found.\")
print()
question = \"What is the weather like in Amsterdam right now?\"
print(f\"Question: {question}\")
answer = run_agent_with_memory(question)
print(f\"Answer: {answer}\")
"""
with open("cosmos.py", "w", encoding="utf-8") as f:
f.write(cosmos)
with open("agent_with_memory.py", "w", encoding="utf-8") as f:
f.write(agent)
print("Done")
'
[System.IO.File]::WriteAllText("$PWD\write_files.py", $code, [System.Text.UTF8Encoding]::new($false))
python write_files.py

Pitfall: Managed Identity RBAC for Cosmos DB

The CosmosClient with DefaultAzureCredential uses your Azure CLI identity locally. That identity needs the Cosmos DB Built-in Data Contributor role on the Cosmos DB account — not a standard Azure RBAC role, but a Cosmos DB data plane role. The spoke deployment should have assigned this automatically via the assignCosmosDBCosmosDbBuiltInDataContributorExecutor deployment. If you get a 403, verify:

az cosmosdb sql role assignment list `
--account-name cosmos-tggi2gmkw22w4 `
--resource-group rg-ai-spoke-dev `
--output table

Your principal ID (8e856fa1-f4c4-4a02-91a5-a6ccc6afc6b3) should appear with role definition ID ending in 00000000-0000-0000-0000-000000000002 (Built-in Data Contributor). If not, assign it:

az cosmosdb sql role assignment create `
--account-name cosmos-tggi2gmkw22w4 `
--resource-group rg-ai-spoke-dev `
--role-definition-id /subscriptions/dc0f4d72-3734-4b03-8884-ccfb9c2c4cc7/resourceGroups/rg-ai-spoke-dev/providers/Microsoft.DocumentDB/databaseAccounts/cosmos-tggi2gmkw22w4/sqlRoleDefinitions/00000000-0000-0000-0000-000000000002 `
--principal-id 8e856fa1-f4c4-4a02-91a5-a6ccc6afc6b3 `
--scope /subscriptions/dc0f4d72-3734-4b03-8884-ccfb9c2c4cc7/resourceGroups/rg-ai-spoke-dev/providers/Microsoft.DocumentDB/databaseAccounts/cosmos-tggi2gmkw22w4

Pitfall: No Connection Strings

Never use Cosmos DB connection strings or account keys in the agent code. The pattern here uses DefaultAzureCredential throughout — locally it picks up your az login identity, in production it uses the spoke’s Managed Identity. This is the NEN 7510 and cVGZ security baseline compliant approach.

Step 4 — Create agent_with_memory.py

$lines = @(
"import json",
"from openai import AzureOpenAI",
"from config import get_config",
"from tools import get_weather, WEATHER_TOOL_DEFINITION",
"from cosmos import save_conversation, get_conversation_history",
"",
"PRINCIPAL_ID = 'steefjan@msn.com'",
"",
"def run_agent_with_memory(user_question: str) -> str:",
" cfg = get_config()",
" apim_base = cfg['APIM_GATEWAY_URL'].rstrip('/').replace('/openai', '')",
"",
" client = AzureOpenAI(",
" azure_endpoint=apim_base,",
" api_key=cfg['APIM_SUBSCRIPTION_KEY'],",
" api_version='2024-02-01',",
" )",
"",
" messages = [{'role': 'user', 'content': user_question}]",
" print(f'Sending request via APIM: {apim_base}')",
"",
" # First LLM call - tool decision",
" response = client.chat.completions.create(",
" model=cfg['CHAT_DEPLOYMENT_NAME'],",
" messages=messages,",
" tools=[WEATHER_TOOL_DEFINITION],",
" tool_choice='auto',",
" )",
"",
" msg = response.choices[0].message",
" messages.append(msg)",
" first_usage = response.usage",
"",
" tool_calls_log = []",
" answer = msg.content or ''",
" total_prompt_tokens = first_usage.prompt_tokens",
" total_completion_tokens = first_usage.completion_tokens",
"",
" # Handle tool calls",
" if msg.tool_calls:",
" for tool_call in msg.tool_calls:",
" args = json.loads(tool_call.function.arguments)",
" print(f' -> Tool call: get_weather({args})')",
" result_str = get_weather(**args)",
" result_json = json.loads(result_str)",
" print(f' -> Tool result: {result_str}')",
"",
" tool_calls_log.append({",
" 'name': tool_call.function.name,",
" 'arguments': args,",
" 'result': result_json,",
" })",
"",
" messages.append({",
" 'role': 'tool',",
" 'tool_call_id': tool_call.id,",
" 'content': result_str,",
" })",
"",
" # Second LLM call - synthesis",
" response2 = client.chat.completions.create(",
" model=cfg['CHAT_DEPLOYMENT_NAME'],",
" messages=messages,",
" )",
" answer = response2.choices[0].message.content",
" total_prompt_tokens += response2.usage.prompt_tokens",
" total_completion_tokens += response2.usage.completion_tokens",
"",
" total_tokens = total_prompt_tokens + total_completion_tokens",
"",
" # Save to Cosmos DB conversations container in the spoke",
" save_conversation(",
" endpoint=cfg['COSMOS_DB_ENDPOINT'],",
" database_name=cfg['DATABASE_NAME'],",
" container_name=cfg['CONVERSATIONS_DATABASE_CONTAINER'],",
" principal_id=PRINCIPAL_ID,",
" question=user_question,",
" tool_calls=tool_calls_log,",
" answer=answer,",
" model=cfg['CHAT_DEPLOYMENT_NAME'],",
" prompt_tokens=total_prompt_tokens,",
" completion_tokens=total_completion_tokens,",
" total_tokens=total_tokens,",
" apim_gateway=apim_base.replace('https://', ''),",
" )",
"",
" return answer",
"",
"if __name__ == '__main__':",
" # Show last 3 conversations before running",
" from config import get_config",
" cfg = get_config()",
" print('=== Recent conversation history ===')",
" history = get_conversation_history(",
" endpoint=cfg['COSMOS_DB_ENDPOINT'],",
" database_name=cfg['DATABASE_NAME'],",
" container_name=cfg['CONVERSATIONS_DATABASE_CONTAINER'],",
" principal_id=PRINCIPAL_ID,",
" limit=3,",
" )",
" if history:",
" for h in history:",
" print(f' [{h[chr(116)+chr(105)+chr(109)+chr(101)+chr(115)+chr(116)+chr(97)+chr(109)+chr(112)]}] Q: {h[chr(113)+chr(117)+chr(101)+chr(115)+chr(116)+chr(105)+chr(111)+chr(110))[:60]}...')",
" else:",
" print(' No previous conversations found.')",
" print()",
"",
" question = 'What is the weather like in Amsterdam right now?'",
" print(f'Question: {question}')",
" answer = run_agent_with_memory(question)",
" print(f'Answer: {answer}')"
)
[System.IO.File]::WriteAllLines("$PWD\agent_with_memory.py", $lines, [System.Text.UTF8Encoding]::new($false))

Run it:

python agent_with_memory.py

A successful run looks like this:

Run it a second time and the history section will show the previous exchange:

Step 5 — Validate in Cosmos DB Data Explorer

Go to the Azure Portal → cosmos-tggi2gmkw22w4 → Data Explorer → cosmos-dbtggi2gmkw22w4 → conversations → Items.

You should see your conversation document with all fields populated. The partition key /principal_id should match steefjan@msn.com.

To query all conversations for a user:

SELECT * FROM c WHERE c.principal_id = 'steefjan@msn.com' ORDER BY c._ts DESC

To get a summary of all runs with token totals:

SELECT c.id, c.timestamp, c.question, c.total_tokens, c.model
FROM c
WHERE c.principal_id = 'steefjan@msn.com'
ORDER BY c._ts DESC

Step 6 — What’s in the Document

Looking at a stored conversation document, every field serves a purpose:

FieldPurpose
idUnique run identifier — traceable back to a specific agent invocation
principal_idPartition key — enables per-user history queries and RBAC scoping
timestampISO 8601 UTC — audit trail, correlatable with APIM logs
questionOriginal user input — searchable for pattern analysis
tool_callsFull tool call log including arguments and results — debugging and audit
answerFinal agent response — quality review and feedback loops
modelModel version — tracks which model version answered which questions
prompt_tokens / completion_tokensCumulative across both LLM calls — accurate per-conversation cost
total_tokensSum of both calls — FinOps input per user per conversation
apim_gatewayGateway used — identifies which hub instance served the request

The token counts here are cumulative across both LLM calls (tool decision and synthesis), yielding a true per-conversation costrather than a per-call figure. This is more useful for FinOps reporting you care about the cost of answering a question, not the cost of individual API calls within that answer.

Pitfalls Summary

PitfallFix
Cosmos DB firewall blocks local IPPortal → Networking → All networks for dev, or add specific IP
403 on Cosmos DB writeAssign Cosmos DB Built-in Data Contributor data plane role to your principal
CosmosResourceNotFoundErrorVerify database name (cosmos-dbtggi2gmkw22w4) and container name (conversations) match exactly
Partition key mismatchContainer was created with /principal_id — every document must include this field
DefaultAzureCredential fails locallyRun az login and ensure the correct subscription is selected
Never use connection stringsUse DefaultAzureCredential throughout — locally via az login, in production via Managed Identity

What the Full Citadel Data Layer Now Looks Like

After this post, the spoke’s data tier is fully active:

StoreWhat it holdsWho writes it
Hub Cosmos DB ai-usage-containerPer-LLM-call usage events (tokens, model, gateway, IP)APIM gateway automatically
Spoke Cosmos DB conversationsPer-run conversation documents (question, tools, answer, cumulative tokens)Agent code explicitly
App Config appcs-tggi2gmkw22w4All configuration keys for the spokeSpoke deployment automatically

The hub’s ai-usage-container captures the infrastructure view of every API call, governed and logged. The spoke’s conversations container captures the application view of every user interaction, structured and queryable. Together, they give you both compliance evidence and application telemetry from a single agent run.

What’s Next

The next post in this series showcases the Citadel Kill Switch and explains how it stops a governed agent when necessary. It details how the five-layer containment system in APIM effectively shuts down the process without affecting the spoke or agent code. The conversation history you’ve created illustrates the clear before-and-after contrast: requests flow to Cosmos DB and then abruptly halt at the gateway layer.

Azure PaaS Integration for Architects: A Practitioner’s Map

If you’ve spent any time in the Azure portal lately, you’ll know the problem isn’t a lack of PaaS services; it’s too many of them, with overlapping capabilities and just enough marketing gloss to make every option look like the right one. App Service or Container Apps? Logic Apps or Functions? Service Bus or Event Grid? The Azure PaaS catalog has grown quickly, and for integration architects specifically, the decisions compound: pick the wrong option at the compute layer, and you’re fighting the platform every time you add a connector, a retry policy, or a compliance control.

This post is a map, not a comparison matrix. I’m grouping the Azure PaaS services that matter to integration work into four layers: compute, integration, data, and governance, and walking through the decision points that arise when designing for a regulated enterprise environment rather than a greenfield demo. If you’ve followed my Logic Apps Agent Loop series or the APIM for AI workloads series, this sits underneath both the platform primer and the deeper posts, which assume you already have read.

Why Azure PaaS still matters to integration architects

IaaS provides you with a VM and asks you to manage everything above it. SaaS gives you the finished product and asks for nothing. PaaS sits in between: the platform owns patching, scaling, and availability, and you own the application logic and configuration. For integration workloads specifically, that trade-off is usually the right one: you rarely need to control the OS of a message broker, but you do need fine-grained control over routing, transformation, and policy enforcement.

The practical test I use: if a service requires you to think about instance sizing, OS patch cycles, or cluster upgrades, it’s leaning IaaS regardless of what the marketing page calls it. If it requires you to think about triggers, bindings, connectors, and scaling rules, it’s PaaS. AKS sits deliberately on that boundary; more on that below.

Layer 1: Compute in Azure PaaS Integration

Azure App Service

Still, the default is web APIs and backend services that don’t need event-driven scaling. App Service gives you deployment slots, built-in autoscale, and managed TLS with minimal ceremony. For integration architects, the main use case is hosting synchronous REST APIs that front a backend system the kind of thing that used to be a WCF service or an on-prem IIS site.

The limitation that catches people out: App Service scales on CPU/memory/queue-length rules, not on arbitrary event volume. If your workload is bursty and event-driven rather than steadily loaded, you’ll either overprovision or look elsewhere.

Azure Functions

The event-driven counterpart. Functions are the right choice when the unit of work is a discrete event: a message landing in a queue, a file arriving in Blob Storage, or an HTTP call that needs to fan out. The Consumption plan gives true scale-to-zero, which matters for cost in low-traffic integration scenarios; the Premium and Flex Consumption plans trade some of that elasticity for warm instances and VNet integration, which most enterprise integration platforms need anyway because you’re rarely allowed to expose a public endpoint without a private link in front of it.

Where Functions get uncomfortable: long-running orchestrations. A single function execution has a timeout, and while Durable Functions solves the orchestration problem, you’re now managing a stateful workflow engine on top of a stateless compute primitive. That’s usually the point where I ask whether Logic Apps would do the job with less code.

Azure Container Apps

The newer entrant is increasingly my default recommendation for anything that needs to run a container without the operational overhead of Kubernetes. Container Apps gives you KEDA-based event-driven scaling, Dapr integration for service-to-service calls and pub/sub, and revision-based traffic splitting all without you touching a node pool. For integration architects building agent-based or microservice-style integration components, this is often the sweet spot: you get container portability (useful if the workload might move, or if you’re standardizing on containers for other reasons) without inheriting cluster lifecycle management.

Azure Kubernetes Service (AKS)

Worth naming even though it’s not strictly Azure PaaS: Microsoft manages the control plane, yet you still own node pool upgrades, networking configuration, and workload scheduling. AKS earns its place when you have genuine Kubernetes-native requirements: custom operators, a multi-team platform where Kubernetes is the common substrate, or workloads that need capabilities Container Apps doesn’t expose yet. For most integration teams, reaching for AKS by default is over-engineering. Reach for it when a specific requirement forces your hand, not because it’s the more “serious” option.


Layer 2: Integration with Azure PaaS

Azure Logic Apps

The workflow orchestration layer with Azure PaaS remains the most direct route to enterprise connectors: SAP, IBM MQ, mainframe hosts, and the long tail of line-of-business systems that lack a modern REST API. Standard Logic Apps (running on the single-tenant model) close most of the gaps that made Consumption Logic Apps hard to use in regulated environments: VNet integration, built-in state management, and per-workflow scaling.

The honest trade-off: Logic Apps designer-first workflows are fast to build and easy for less code-heavy teams to maintain, but they get harder to reason about and harder to code-review once a workflow grows past a certain complexity. I’ve found the practical ceiling is somewhere around “a dozen actions with a couple of branches.” Past that, either decompose into smaller workflows or move the logic into a Function.

Azure API Management

Not just a gateway for integration architects, APIM is where governance actually gets enforced. Rate limiting, authentication, request/response transformation, and policy-based routing all live here, in front of whatever compute layer is doing the real work. If you’re building any platform where multiple consumers hit a shared set of backend capabilities, APIM is the control point that lets you change backend implementations without breaking consumers and enforce policy without touching application code.

The thing worth planning for early: policy authoring in APIM is a distinct skill, separate from the languages your team already knows. Please budget time for the team to learn the policy XML dialect rather than treating it as an afterthought. Badly written policies are a common source of latency and hard-to-diagnose failures.

Azure Service Bus

The durable, ordered, transactional messaging backbone. Reach for Service Bus when you need guaranteed delivery, sessions for ordered processing, or transactional message handling across multiple operations. Topics and subscriptions give you pub/sub without standing up a separate broker.

Azure Event Grid

The lightweight, high-throughput event router. Where Service Bus is about reliable delivery of business messages, Event Grid is about routing high-volume, fire-and-forget events resource state changes, custom application events, IoT telemetry to whichever subscriber cares about them. The two are frequently used together: Event Grid fans out a notification, and a subscriber puts a durable message on Service Bus for guaranteed processing.

A rule of thumb I use with teams new to Azure integration: if losing a message would be a business incident, it belongs on Service Bus. If losing a message would just mean a missed notification, Event Grid is fine.


Layer 3: Data in Azure PaaS

Integration architecture lives and dies by what’s underneath it, and the PaaS data services matter as much as the compute and messaging layers.

Azure SQL Database remains the default for relational, transactional workloads with a need for strong consistency think reference data, transactional state, anything with real foreign-key relationships. In addition, Azure Cosmos DB earns its place when you need global distribution, flexible schema, or the kind of horizontal scale that a single SQL instance won’t give you cheaply; it’s also increasingly the default choice for conversation and state storage in agentic workloads, given its low-latency reads and flexible document model. Finally, Azure Cache for Redis sits in front of both, absorbing read load and giving you a fast, ephemeral store for session state or short-lived coordination data.

The mistake I see most often: teams default to Cosmos DB because it’s the “modern” choice, then discover they actually needed relational integrity and end up hand-rolling consistency checks that SQL would have given them for free. Pick based on the access pattern, not the reputation.


Layer 4: Governance and identity for Azure PaaS

This is the layer that separates a proof of concept from something you can run in a regulated industry. Microsoft Entra ID and managed identities remove the need for connection strings and API keys scattered across configuration files. Each of the Azure PaaS services above should authenticate via managed identity. Key Vault holds what can’t be a managed identity (third-party API keys, certificates). Azure Policy and Microsoft Defender for Cloud provide the guardrails and posture visibility that an auditor or security team will ask for. Azure Monitor and Application Insights are non-negotiable for integration platforms, especially when a message fails somewhere in a chain of five services. Distributed tracing is the difference between a five-minute diagnosis and a day of log archaeology.


Layer 5: The gap that agentic workloads expose

Everything above holds for conventional integration platforms. Agentic AI workloads add a wrinkle that a recent round of discussion on LinkedIn I saw around an enterprise agent architecture diagram put well: the model is arguably the least differentiated part of a production agent deployment. Identity, permissions, observability, governance, and reliable orchestration are what separate a working demo from something you can run against real systems, and a few of those deserve to be called out specifically for integration architects, because they don’t map cleanly onto the governance layer above.

Idenitity

Identity secures who the agent is, not what it does. Entra ID and managed identity answer “Is this caller who it claims to be?” They don’t address what happens when a poisoned tool result or a manipulated retrieved document changes the agent’s next action mid-reasoning loop. Prompt injection rides in through the RAG layer and tool outputs inside the loop, where identity checks at the perimeter don’t reach. The practical implication for PaaS design is that authorization needs to occur per action, not just per identity. This is exactly what APIM policy scoping and per-tool consent in Logic Apps and AI Foundry connectors are for: to treat each tool call as its own authorization decision, rather than an inherited privilege from a validated caller.

Recovery

Recovery means compensating actions, not just retries. Agent actions have side effects across systems: a ticket got created, a record got updated, an email went out. A failed step three actions into an agent loop can’t just retry from the top; it needs a saga-style compensating action to undo what already happened. Service Bus sessions and Logic Apps’ native support for scoped try/catch-with-compensation are the building blocks here — but the compensation logic has to be designed in explicitly, because neither service provides it by default.

Evaluation

Evaluation and drift detection are a first-class layer, not an afterthought. Application Insights and Azure Monitor provide operational observability into latency, error rates, and throughput. They don’t tell you if the agent’s outputs are quietly degrading in quality over time. That’s a separate concern, and one worth budgeting for from the start rather than bolting on after the first bad production incident.

The questions worth asking before an agent goes anywhere near a real system: what did it access, what tool did it call, why did it act, what policy constrained it, what happened when it failed, and who owns the outcome. If a PaaS architecture can’t answer all six, the gap isn’t in the model; it’s in the platform around it.


Azure PaaS Integration decisions: a framework, not a decision tree for integration architects

None of these layers are picked in isolation; the compute choice constrains the integration pattern, and the integration pattern constrains what the data layer needs to support. When I’m working through this with a team, the questions I ask in order are:

  1. Is the trigger an event or a schedule/request? Event-driven points toward Functions or Container Apps with KEDA; request-driven points toward App Service or APIM-fronted compute.
  2. Does a human or a low-code team need to maintain this workflow? If yes, Logic Apps earns serious consideration even if a Function would be more “elegant.”
  3. What’s the cost of losing a message? Business-critical → Service Bus. Best-effort notification → Event Grid.
  4. Does the data need strong relational integrity, or flexible scale? SQL for the former, Cosmos DB for the latter — and don’t let the “modern” label make the decision for you.
  5. Is everything behind managed identity and traced end to end? If the answer is no anywhere in the chain, that’s the next thing to fix, not the last.

Azure PaaS Integration Conclusion

That’s the shape of it. In practice, most enterprise integration platforms end up using several of these services together: API Management fronting a mix of Logic Apps and Functions, backed by Service Bus for reliable delivery and Cosmos DB or SQL for state and the architecture work is less about picking a single winner than about drawing clean boundaries between them.

Azure Logic Apps Agent Loop Production Operations

Part 7 of 7 in the Logic Apps Agent Loop series

Part 6 covered the security stack for agentic workflows: Easy Auth, Managed Identity, and Key Vault. This final post closes the series with Azure Logic Apps agent loop production operations: how to monitor agent loops with Application Insights, what the pricing model looks like across Standard and Consumption, the key platform limits to be aware of, and how to deploy agentic workflows through a repeatable DevOps pipeline.

By the end of this post, you will have a complete picture of what it takes to run an agentic workflow in production, not just to build one.

Azure Logic Apps agent loop production monitoring with Application Insights

The run history you have used throughout this series is the starting point for understanding what an agent loop did and why. For production workloads you need more: aggregated metrics across multiple runs, structured log queries, alerting on failures, and tracing across distributed systems. Application Insights provides all of this for Standard logic apps.

Enabling Application Insights

If you did not enable Application Insights when you created la-agent-loop, you can add it after deployment:

  1. In the Azure portal, open your la-agent-loop logic app resource
  2. Navigate to Application Insights under Settings in the left sidebar
  3. Click Turn on Application Insights
  4. After the pane updates, click Apply → Yes
  5. Click View Application Insights data to open the dashboard

Application Insights begins collecting telemetry from that point forward; it does not backfill historical run data.

What Application Insights captures for agent loops

For Standard agentic workflows, Application Insights captures enhanced telemetry beyond what the run history provides. Key data points include:

Requests — each workflow trigger appears as an incoming request, with duration, success/failure status, and HTTP response code.

Dependencies — each tool call the agent makes appears as a dependency call, with the target service, duration, and result. Moreover, for an agent loop that invokes Azure OpenAI and Azure AI Search, you will see both as dependency entries, making it straightforward to identify which tool call is slowest.

Exceptions — any workflow failure surfaces as an exception with a full stack trace, correlated to the specific run and iteration where it occurred.

Custom metrics — Logic Apps emits custom metrics for agent loop iterations, token usage, and tool invocation counts. These are queryable via Kusto (KQL) in the Logs blade.

Useful KQL queries for agent loops

You can query agent loop run durations for, let’s say, over the last 72 hours:

requests | where timestamp > ago(72h) | where name contains "agent" | summarize avg(duration), max(duration), count() by bin(timestamp, 1h) | render timechart

To identify failed agent loop runs:

requests | where timestamp > ago(72) | where success == false | project timestamp, name, duration, resultCode, cloud_RoleInstance | order by timestamp desc

To track tool call durations:

dependencies | where timestamp > ago(24h) | where type == "HTTP" | summarize avg(duration), count() by target | order by avg_duration desc

Reading the run history for agent loops

The run history in the Logic Apps portal is the fastest way to debug a specific agent loop run. For agentic workflows it shows more than a conventional run history — each agent action expands to show its iterations, and each iteration shows the model’s reasoning, the tool calls it made, and the results it received.

The Agent activity tab is the most useful view for agentic workflows. It shows the conversation between the model and the tools in chronological order, every message the model generated, every tool it invoked, and every result it received. The agent loop reveals its chain of thought.

Key things to look for in the run history:

  • Iteration count — how many Think → Act → Observe cycles the loop ran. A loop that runs the maximum number of iterations (default 100) without completing is a signal that the instructions are ambiguous or the tools are not returning usable results.
  • Tool call inputs and outputs — expand each tool call to see exactly what the model passed as parameters and what the tool returned. This is the fastest way to diagnose a tool that is returning unexpected data.
  • Token usage — the metadata output of each agent action shows total tokens, prompt tokens, and completion tokens. High prompt token counts indicate the conversation history is growing large — consider enabling agent history reduction.

Azure Logic Apps agent loop production pricing: Standard versus Consumption

The pricing model for agentic workflows differs between Standard and Consumption, and it differs significantly from conventional Logic Apps pricing.

Standard

Standard logic apps use a fixed App Service Plan pricing model — you pay for the compute capacity whether the workflow is running or not. Agentic workflows on Standard do not incur extra charges beyond the base App Service Plan cost. However, every Azure OpenAI call the agent makes is billed separately against your Azure OpenAI resource at standard token rates.

For the la-agent-loop workflows in this series:

  • The Standard logic app itself: App Service Plan (Workflow Standard WS1 or higher)
  • Each GPT-4o call: billed to aoai-demo-ptu at your PTU reservation rate
  • Azure AI Search queries (if used): billed separately at Search tier rates

The practical implication is that Standard agentic workflow costs scale with model usage, not with workflow execution count. A loop that runs five iterations and calls GPT-4o five times costs five times more in model tokens than a loop that resolves in one iteration.

Consumption

Consumption agentic workflows use a pay-as-you-go model. Agent loop pricing is based on the number of tokens each agent action uses and appears as Enterprise Units on your bill. This is a different billing unit from the standard Consumption action executions — each token consumed by the agent is metered separately.

The Consumption agent loop is also subject to throttling based on token usage — unlike Standard, which is constrained only by the App Service Plan compute capacity.

For production workloads with predictable, high-volume agent loop usage, Standard with a PTU Azure OpenAI deployment is the more cost-predictable option. For low-volume or experimental workloads, Consumption pay-as-you-go avoids the fixed App Service Plan cost.

Known limits for agentic workflows

Before going to production, be aware of the current platform limits:

Tool constraints — tools can only contain actions, not triggers. A tool must start with an action and always contains at least one action. Control flow actions (conditions, loops, switches) are not supported inside tools. A tool only works inside the agent loop where it is defined — it cannot be shared across agent actions.

Consumption-specific limits — Consumption agentic workflows can only be created in the Azure portal, not Visual Studio Code. The AI model can come from any region, so data residency for a specific region is not guaranteed for data the model handles. The agent action is throttled based on token usage.

Agent history — by default the agent loop accumulates the full conversation history across iterations. For long-running loops this can push the context length toward the model’s limit. Enable agent history reduction in the agent action’s Settings tab to manage this. The default strategy is token count reduction with a ceiling of 128,000 tokens — adjust this based on your model’s context window and your scenario’s complexity.

Deploying agentic workflows through a DevOps pipeline

Standard logic apps are built on the Azure Functions runtime and deploy the same way as any other Standard logic app — via zip deploy, Azure Pipelines, or GitHub Actions. The workflow definitions are JSON files on disk, making them version-controllable and deployable through standard CI/CD patterns.

What to include in source control

For an agentic workflow project, the key files to version-control are:

  • sequential-agents/workflow.json — the sequential agent loop definition
  • sample/workflow.json — the autonomous agent from Post 2
  • mcp-research/workflow.json — the MCP research workflow from Post 4
  • connections.json — connection references (without credentials — those go in Key Vault)
  • host.json — Logic Apps host configuration
  • local.settings.json — local development settings (excluded from source control, .gitignore)

Deploying with Azure CLI

The simplest production deployment from a CI/CD pipeline uses the Azure CLI:

# Zip the logic app project zip -r la-agent-loop.zip . -x "*.git*" "local.settings.json"

# Deploy to Azure az logicapp deployment source config-zip \ --name la-agent-loop \ --resource-group rg-ai-solutions \ --src la-agent-loop.zip

Environment-specific configuration

Agent connections and app settings differ between development and production environments. Use Azure CLI or Bicep to set environment-specific app settings as part of the deployment pipeline:

az logicapp config appsettings set \ --name la-agent-loop \ --resource-group rg-ai-solutions \ --settings \ agent_openAIEndpoint="https://aoai-prod.openai.azure.com/" \ OPENAI__endpoint="https://aoai-prod.openai.azure.com/"

This keeps environment-specific values out of source control and injected at deploy time — the standard twelve-factor app pattern applied to Logic Apps.

Closing the series

This post closes a seven-part series on Azure Logic Apps agent loop production operations, from first principles through to observability, pricing, and DevOps deployment. The series covered:

  1. Why the agent loop is a different design paradigm from conventional workflow automation
  2. The anatomy of a single agent loop — trigger, instructions, model, and tools
  3. Autonomous versus conversational agentic workflows: when to use each
  4. Building tools: connectors, custom connectors, and MCP servers
  5. Multi-agent patterns: prompt chaining, routing, handoff, and orchestrator-workers
  6. Securing agentic workflows: Easy Auth, Managed Identity, and Key Vault
  7. Observability, pricing, and production operations — this post

The agent loop is still a rapidly evolving capability in Azure Logic Apps. The platform limitations documented throughout this series Foundry Models connection persistence, API Center MCP wizard regional constraints, Foundry OpenAPI tool network restrictions will be addressed in future platform releases. The architectural patterns, however, are stable: the four building blocks of an agent loop, the three tooling layers, the four multi-agent patterns, and the two-concern security model will remain the right mental model for this platform regardless of how the surface-level tooling evolves.

Azure Logic Apps Agentic Workflow Security in Production

Part 6 of 7 in the Logic Apps Agent Loop series

Part 5 covered multi-agent patterns in the Azure Logic Apps agentic workflow series. Each pattern extends your agent’s reach, but that reach comes with a security cost. The more capable and connected your agent, the more important it is to understand who can call it and under what conditions. This post covers the expanded caller surface, the developer key’s limitations, and the full production security stack.

Conventional Logic Apps workflows have a bounded caller surface. The callers are known systems: a scheduler, a service bus, and an HTTP client you control. The authentication model is straightforward: SAS tokens, Managed Identity, and IP filtering. Agentic workflows fundamentally change this, particularly conversational ones. When you expose a chat interface to external callers, those callers can be people, other agents, MCP servers, or automation clients from networks you do not control. The security model has to change with the threat model.

The expanded caller surface

The shift from nonagentic to agentic workflows introduces a qualitatively different caller population. In a nonagentic workflow the trigger is called by a known system at a known time for a known reason. In a conversational agentic workflow the trigger is called by:

  • Human users interacting through an external chat client
  • External agents invoking the workflow as a tool
  • MCP servers routing requests through the workflow
  • Automation clients from untrusted or unknown networks

Each of these caller types introduces different identity, trust, and access control requirements. A billing system calling a webhook is easy to reason about. An external agent calling your workflow from an unknown network at unpredictable intervals is not.

This expanded surface area is why Microsoft’s documentation draws a sharp distinction between the developer key used during design and testing in the Azure portal and proper production authentication. Understanding that distinction is the starting point for securing any agentic workflow.

The developer key: what it is and what it is not

Understanding the developer key’s limitations is the starting point for any serious Azure Logic Apps agentic workflow security implementation. When you test a conversational agentic workflow in the Logic Apps designer, the Azure portal authenticates your test calls using a developer key. The developer key is a convenience mechanism that lets you skip manual authentication setup during development. It fires automatically when you run a workflow, call a Request trigger, or interact with the integrated chat interface.

The developer key has five hard limitations that make it unsuitable for production:

  • It is not a substitute for Easy Auth, Managed Identity, federated credentials, or signed SAS callback URLs.
  • In addition, it is designed for large or untrusted caller populations, agent tools, or automation clients.
  • It is also not a per-user authorization mechanism; it has no granular scopes or roles.
  • And finally, it is not governed by Conditional Access policies at the request execution layer, only at the portal sign-in layer. And it is not intended for programmatic or CI/CD usage.

The developer key is linked to a specific user and tenant based on an Azure Resource Manager bearer token. Because of that binding, you cannot distribute it externally. It is, in the Microsoft documentation’s own framing, a mechanism for quick testing before you formalize authentication, not a path to production.

Azure Logic Apps agentic workflow security: Standard versus Consumption

The right production authentication mechanism depends on your Logic Apps hosting model.

Setting up Managed Identity for backend connections

Easy Auth secures who can call your agentic workflow. Managed Identity secures what your workflow can call. These are two distinct security concerns and both need to be addressed in production.

When your agent invokes a tool, Azure OpenAI, Azure AI Search, a storage account, or a Service Bus namespace, that call needs to be authenticated. The default approach during development is often to store an API key or connection string in app settings. In production, replace these with Managed Identity connections wherever possible. This removes credentials from app settings entirely. The logic app authenticates to backend services using its Azure AD identity, which is governed by RBAC, auditable, and revocable without rotating keys.

  1. Go to your la-agent-loop resource → Identity → System assigned → turn Status to On
  2. Save — Azure assigns a service principal to the logic app
  3. In each target resource (Azure OpenAI, AI Search, Storage), go to Access control (IAM) → Add role assignment
  4. Assign the appropriate role to the logic app’s Managed Identity:
    • Azure OpenAI: Cognitive Services OpenAI User
    • Azure AI Search: Search Index Data Reader
    • Azure Blob Storage: Storage Blob Data Reader
  5. In the Logic Apps connections, switch from API key authentication to Managed Identity for each backend service where possible.

Note: Managed Identity authentication for the agent model connection is only supported when the model type is AzureOpenAI. If your workflows use the MicrosoftFoundry model type, as in this series, the agent connection must use Key authentication. Managed Identity remains the right choice for all other backend connections such as Azure AI Search, Blob Storage, and Service Bus.

Setting up Easy Auth for your Azure Logic Apps agentic workflow

For Standard logic apps, the production authentication path is Easy Auth, also known as App Service Authentication. Easy Auth is an App Service platform feature that sits in front of your logic app and enforces identity-based authentication on every incoming request before it reaches your workflow.

When you enable Easy Auth on a Standard logic app, external callers, whether human users, external agents, or MCP servers, must present a valid identity token. Easy Auth validates the token against Microsoft Entra ID before allowing the request through. This gives you full Conditional Access policy enforcement, per-user identity, token revocation, and audit logging, the full production security stack.

To set up Easy Auth on a Standard logic app:

  1. In the Azure portal, open your la-agent-loop logic app resource
  2. Navigate to Authentication in the left sidebar under Settings
  3. Click Add identity provider
  4. Select Microsoft as the identity provider
  5. Under App registration, select an existing registration or choose Create new app registration and name it la-agent-loop-auth
  6. Under Supported account types, select Current tenant — single tenant for internal workloads
  7. Set Unauthenticated requests to HTTP 401 Unauthorized: recommended for APIs
  8. Leave Token store enabled
  9. Click Add

Note: Easy Auth operates at the App Service host level, before the Logic Apps runtime processes the request. Authentication failures are rejected at the infrastructure layer with a 401 the workflow never executes and no run history entry is created for unauthenticated calls.

Consumption: OAuth 2.0 with Microsoft Entra ID

For Consumption logic apps, configure an agent authorization policy on the logic app resource using OAuth 2.0 with Microsoft Entra ID. This provides equivalent identity enforcement to Easy Auth for the Consumption hosting model. For the full configuration steps, see Create conversational agent workflows in Azure Logic Apps on Microsoft Learn.

Key Vault for secrets that cannot use Managed Identity

Not every connection in an Azure Logic Apps agentic workflow supports Managed Identity. Where API keys or connection strings are unavoidable, store them in Azure Key Vault and reference them from Logic Apps app settings using the Key Vault reference syntax:

@Microsoft.KeyVault(SecretUri=https://your-keyvault.vault.azure.net/secrets/your-secret/)

This keeps credentials out of app settings in plain text, provides centralized rotation, and gives you audit logs of every secret access. The Standard logic app accesses Key Vault using its Managed Identity; no separate credentials are needed for the vault itself.

Network controls for Standard workflows

Standard logic apps run on the App Service infrastructure, which gives you network-level controls that Consumption workflows do not have:

Private endpoints allow your logic app to receive inbound traffic only from within a virtual network, removing public internet exposure entirely. This is the recommended configuration for production agentic workflows that serve internal users or agents.

VNet integration allows your logic app to make outbound calls to services within a virtual network, including on-premises systems, private Azure services, and internal APIs, without exposing those services to the internet.

IP access restrictions let you restrict inbound traffic to specific IP ranges at the App Service level, providing a lighter-weight alternative to private endpoints for scenarios where full network isolation is not required.

For production agentic workflows processing sensitive data, patient records, financial data, internal business intelligence, and private endpoints with VNet integration is the right starting point.

Azure Logic Apps agentic workflow security checklist

Before going live with any agentic workflow:

  • Easy Auth configured with Microsoft Entra ID (Standard) or OAuth 2.0 agent authorisation policy (Consumption)
  • Developer key not used or referenced in any production caller
  • Managed Identity enabled on the logic app and assigned to all backend services
  • API keys and connection strings moved to Key Vault references
  • Private endpoints configured for Standard workflows handling sensitive data
  • Conditional Access policies applied to the Entra ID app registration backing Easy Auth
  • Run history access restricted to authorised operations personnel

What comes next

The final post in this series concludes with operations: Application Insights integration, agent loop pricing, run history analysis, and deployment of agentic workflows through a CI/CD pipeline. Part 7 covers everything you need to run agent loops confidently in production.

Microsoft Foundry Citadel Platform Azure: A Practitioner’s Deployment Guide

Microsoft Foundry Citadel Platform on Azure is a layered AI governance architecture that delivers production-ready agent deployments with unified governance, end-to-end observability, and centralized policy enforcement via Azure API Management. It is still in preview, and the documentation assumes a degree of familiarity with Azure infrastructure that not everyone has on day one. This post walks through what it actually takes to get a working hub-and-spoke running in Sweden Central, including the pitfalls, so you can decide whether it is a viable starting point for your own AI platform journey.

What Citadel Is (and Is Not)

Before touching the tooling, it helps to understand what Citadel actually deploys. The architecture has four layers:

The first layer — Governance Hub is the runtime enforcement plane: Azure API Management as a centralized AI gateway, Azure API Center as a model registry, and supporting services for content safety, PII detection, cost attribution, and usage telemetry.

Subsequent second layer 2 — AI Control Plane provides observability via the Foundry Control Plane: agent-level execution traces, AI evaluations in development and production, red-teaming, drift monitoring, and fleet dashboards.

The next third layer — Agent Identity transforms agents into managed enterprise assets via Microsoft Entra ID, with lifecycle management, sponsorship models for human accountability, and shadow AI discovery.

Finally, the last fourth layer, 4 — Security Fabric, weaves Defender, Purview, and Entra across the other three layers for real-time threat intelligence, data governance, and compliance automation.

For this guide, we deploy Layer 1 (the Governance Hub via the AI Hub Gateway Solution Accelerator) and a Layer 1/2 spoke (via the AI Landing Zone Bicep). Layers 3 and 4 reference existing Azure services (Entra ID, Defender, Purview) that you integrate separately.

Important: Citadel is currently in preview. The repos, parameter schemas, and CLI commands will change. Treat everything in this post as a starting point, not a stable reference.

Prerequisites

Before you start, make sure you have:

  • An Azure subscription with Azure OpenAI access approved (aka.ms/oaiapply)
  • Microsoft.Authorization/roleAssignments/write on the subscription (Owner or User Access Administrator role)
  • Azure CLI installed and authenticated (az login)
  • Azure Developer CLI (azd) installed
  • Node.js — use v20 LTS, not v24. Node 24 on Windows has a known issue where npm bundles are incomplete, causing MODULE_NOT_FOUND errors on npm-cli.js and npm-prefix.js when azd tries to package Logic App components

If you run into npm issues on Windows, the cleanest workaround is Azure Cloud Shell, where Node, npm, az, and azd are all pre-installed and healthy.

Part 1: Deploying the Microsoft Foundry Citadel Governance Hub

Clone the AI Hub Gateway Solution Accelerator:

git clone https://github.com/Azure-Samples/ai-hub-gateway-solution-accelerator.git
cd ai-hub-gateway-solution-accelerator

Create your azd environment:

azd auth login
azd env new ai-hub-gateway-dev
azd env set AZURE_LOCATION swedencentral

Create a parameters file at infra/main.parameters.json. The key decisions:

Model versions matter. At the time of writing, gpt-4o-mini versions 2024-07-18 and 2024-10-18 are retired. Use gpt-4o version 2024-11-20 with GlobalStandard SKU. Always verify current model availability at aka.ms/aoai-regions before deploying these changes frequently.

{
"$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentParameters.json#",
"contentVersion": "1.0.0.0",
"parameters": {
"environmentName": { "value": "ai-hub-gateway-dev" },
"location": { "value": "swedencentral" },
"apimSku": { "value": "Developer" },
"openAiInstances": {
"value": {
"openAi1": {
"name": "openai1",
"location": "swedencentral",
"deployments": [
{
"name": "chat",
"model": { "format": "OpenAI", "name": "gpt-4o", "version": "2024-11-20" },
"sku": { "name": "GlobalStandard", "capacity": 20 }
},
{
"name": "embedding",
"model": { "format": "OpenAI", "name": "text-embedding-3-large", "version": "1" },
"sku": { "name": "Standard", "capacity": 20 }
}
]
}
}
},
"provisionFunctionApp": { "value": false },
"createAppInsightsDashboard": { "value": false },
"enableAIGatewayPiiRedaction": { "value": true },
"enableAIModelInference": { "value": true }
}
}

Deploy:

azd up

Expect 45–90 minutes. APIM Developer SKU is the slow component. If the deployment fails partway through, re-run azd up it is idempotent and will pick up where it left off.

Pitfall: Managed Identity Race Condition

You will likely see this error on first attempt:

BadRequest: The provided principal ID was not found in the AAD tenant(s)

This is a known race condition — the Managed Identity is created but has not yet propagated in Entra ID before the role assignment fires. Re-run azd up without any changes and it will succeed.

Validate the Hub

Once deployed, run:

azd env get-values | grep APIM

You will get your APIM gateway URL. Test it with a chat completion:

$headers = @{
"Content-Type" = "application/json"
"api-key" = "<YOUR_APIM_SUBSCRIPTION_KEY>"
}
$body = '{"messages":[{"role":"user","content":"Hello from the AI Hub Gateway!"}],"max_tokens":100}'
Invoke-RestMethod `
-Uri "https://<your-apim>.azure-api.net/openai/deployments/chat/chat/completions?api-version=2024-02-01" `
-Method POST -Headers $headers -Body $body

A successful response with content_filter_results and prompt_filter_results confirms Content Safety and PII redaction are active. Token usage in the response confirms Cosmos DB is logging for cost attribution.

Part 2: Deploying a Citadel Platform Agent Spoke on Azure

The spoke is deployed from the AI Landing Zone Bicep repo. Download it as a ZIP (no GitHub account required):

https://github.com/Azure/bicep-ptn-aiml-landing-zone/archive/refs/heads/main.zip

Extract and navigate to the folder. Create a resource group for the spoke:

az group create --name rg-ai-spoke-dev --location swedencentral

Create a spoke.parameters.json file. Several things to know upfront:

The parameter schema is not the same as the Citadel README suggests. The actual template parameters differ from the example file. Key differences discovered in practice: aiFoundryLocation does not exist as a separate parameter; deployMcp, greenFieldDeployment, deployPostgres, and useCMK are not in this version of the template; and solutionStorageAccountName is simply storageAccountName.

The modelDeploymentList uses nested objects, not flat properties:

"modelDeploymentList": {
"value": [
{
"name": "chat",
"model": { "format": "OpenAI", "name": "gpt-4o", "version": "2024-11-20" },
"sku": { "name": "GlobalStandard", "capacity": 20 },
"canonical_name": "CHAT_DEPLOYMENT_NAME",
"apiVersion": "2025-04-01-preview"
},
{
"name": "text-embedding",
"model": { "format": "OpenAI", "name": "text-embedding-3-large", "version": "1" },
"sku": { "name": "Standard", "capacity": 10 },
"canonical_name": "EMBEDDING_DEPLOYMENT_NAME",
"apiVersion": "2025-04-01-preview"
}
]
}

containerAppsList cannot be an empty array. The template references containerApps[0] internally and will fail validation if the array is empty. Pass at least one placeholder entry.

Deploy:

az deployment group create `
--resource-group rg-ai-spoke-dev `
--template-file main.bicep `
--parameters @spoke.parameters.json

Pitfalls in the Spoke Deployment

AI Search Standard SKU capacity exhaustion. Sweden Central frequently runs out of AI Search Standard SKU capacity. You will see ResourcesForSkuUnavailable. This affects both the standalone Search Service and the AI Foundry Agent Service’s internal Search instance. Disable both:

"deploySearchService": { "value": false },
"deployAAfAgentSvc": { "value": false }

You can re-enable them later once capacity is available, or deploy Search in a different region.

Soft-deleted resources block redeployment. Azure retains soft-deleted Cognitive Services accounts, Key Vaults, and App Configuration stores for up to 90 days. If you delete a resource group and redeploy, the deployment will fail with FlagMustBeSetForRestore or NameUnavailable. Purge them explicitly before redeploying:

# List and purge soft-deleted resources
az keyvault list-deleted --subscription <sub-id> -o table
az keyvault purge --name <name> --location swedencentral
az appconfig list-deleted --subscription <sub-id> -o table
az appconfig purge --name <name> --location swedencentral --yes
az cognitiveservices account list-deleted --subscription <sub-id> -o table
az cognitiveservices account purge --name <name> --location swedencentral

Key Vault purges are slow — allow 2–5 minutes per vault.

Bastion subnet ID resolution fails with networkIsolation=false. When you disable network isolation, the template passes a relative subnet ID to Bastion instead of a fully qualified resource ID. Disable Bastion, Jump VM, and NAT Gateway for the dev spoke:

"deployBastion": { "value": false },
"deployJumpbox": { "value": false },
"deployVM": { "value": false },
"deployNatGateway": { "value": false }

Write parameters files without BOM. On Windows, Out-File -Encoding utf8 adds a Byte Order Mark that causes az deployment to fail with Unable to parse parameter. Use either:

$content | Out-File -FilePath "spoke.parameters.json" -Encoding utf8NoBOM
# or
[System.IO.File]::WriteAllText("spoke.parameters.json", $content, [System.Text.UTF8Encoding]::new($false))

Part 3: Wiring the Citadel Spoke to the Azure APIM Hub

Add the hub’s APIM gateway URL and subscription key to the spoke’s App Configuration:

az appconfig kv set `
--name <spoke-appconfig-name> `
--key "APIM_GATEWAY_URL" `
--label "ai-lz" `
--value "https://<your-apim>.azure-api.net/openai" `
--yes
az appconfig kv set `
--name <spoke-appconfig-name> `
--key "APIM_SUBSCRIPTION_KEY" `
--label "ai-lz" `
--value "<YOUR_APIM_KEY>" `
--yes

Note: az cognitiveservices account connection create with a YAML file for creating an APIM connection in AI Foundry has known bugs in the current CLI version and will throw NoneType or codec errors. Create this connection via the Azure AI Foundry portal UI instead.

Validate End-to-End

$headers = @{
"Content-Type" = "application/json"
"api-key" = "<YOUR_APIM_KEY>"
}
$body = '{"messages":[{"role":"user","content":"Hello from the Citadel spoke!"}],"max_tokens":50}'
Invoke-RestMethod `
-Uri "https://<your-apim>.azure-api.net/openai/deployments/chat/chat/completions?api-version=2024-02-01" `
-Method POST -Headers $headers -Body $body

A successful response with content_filter_results, prompt_filter_results, and usage confirms the full Citadel loop: spoke → APIM gateway → Azure OpenAI → governance telemetry.

What the Microsoft Foundry Citadel Platform Deploys

After following this guide, your rg-ai-hub-gateway-dev resource group contains:

  • APIM gateway with content safety, PII redaction, token rate limiting, and cost attribution policies
  • Azure OpenAI with gpt-4o and text-embedding-3-large
  • Cosmos DB for usage event logging
  • Logic App for usage processing
  • Application Insights for gateway telemetry

Your rg-ai-spoke-dev resource group contains:

  • AI Foundry account and project
  • gpt-4o and text-embedding-3-large deployments
  • Cosmos DB with a conversations container
  • Key Vault, App Configuration, Storage Account, Application Insights, Log Analytics

App Configuration is fully populated with canonical keys (CHAT_DEPLOYMENT_NAME, AI_FOUNDRY_PROJECT_ENDPOINT, COSMOS_DB_ENDPOINT, and more) ready for agent applications to consume.

This Is a Dev Setup — Here Is What Changes for Non-Prod and Production

The configuration above is a starting point, not a production blueprint. Key differences when moving up the environment stack:

APIM SKU. Developer SKU has no SLA and no VNet support. Switch to Premium SKU for non-prod and production. This significantly increases cost and deployment time but enables private networking, multi-region, and availability zones.

Network isolation. For production, set networkIsolation=true and wire the spoke VNet to your hub VNet via peering (hubIntegrationHubVnetResourceId). This requires coordinating private DNS zones across the hub and spoke. The template supports bringing existing DNS zones via the existingPrivateDnsZone* parameters.

AI Search. Re-enable deploySearchService and deployAAfAgentSvc for non-prod and production. If Sweden Central remains capacity-constrained on Standard SKU, deploy Search to a paired region (East US 2 works well) using the searchServiceLocation parameter.

Bastion and Jump VM. For production with networkIsolation=true, re-enable deployBastion and deployJumpbox so operators can access resources inside the private VNet without public endpoints.

Separate parameter files per environment. Maintain spoke.parameters.dev.json, spoke.parameters.nonprod.json, and spoke.parameters.prod.json with environment-specific values. Use a deployment pipeline (GitHub Actions or Azure DevOps) to apply them consistently.

Model versions. Pin specific model versions in parameters files and validate availability in your target region before each deployment. Azure OpenAI model lifecycle moves fast; versions retire on 18-month cycles, and regional availability varies.

Preview Caveats

Citadel is in active development. Several things you should expect to change:

The parameter schemas for both the hub and spoke accelerators will evolve. Parameters discovered missing or renamed in this guide will likely be reorganized again as the repos mature. Always check the actual main.bicep parameter definitions rather than relying on example files.

The az cognitiveservices account connection create CLI command for AI Foundry connections is incomplete at the time of writing. This will improve as the Foundry CLI surface area matures.

The citadel-v1 branch in the AI Hub Gateway repo is flagged as the recommended path for new deployments. By the time you read this, it may have become the default branch with a cleaner deployment experience.

Regional capacity for AI Search Standard SKU fluctuates. Sweden Central is a high-demand region for AI workloads plan for capacity constraints in any SKU beyond Basic for dev scenarios.

Conclusion

Citadel gives you a credible, opinionated starting point for enterprise AI governance on Azure APIM as the AI gateway, AI Foundry as the agent runtime, Cosmos DB for conversation state, and App Configuration as the configuration backbone. Getting it running today requires navigating several rough edges: parameter schema inconsistencies, soft-delete cascades, model version deprecations, regional capacity constraints, and Windows-specific tooling issues.

None of these are blockers. They are the expected friction of working with a platform in active preview. The underlying architecture is sound, and the pieces that do work, APIM governance policies, Content Safety integration, App Config population, and AI Foundry project wiring deliver real value immediately.

If you are building an AI platform for your organization, a Citadel dev setup is a reasonable first step. Treat it as a learning environment to understand the architecture, validate the tooling, and build the parameter files you will need for non-prod and production. Then evolve it deliberately: add network isolation, re-enable Search and Agent Services as capacity allows, and adopt the Citadel contracts (AI Access Contract, AI Publish Contract) to formalize the hub-spoke integration as your agent portfolio grows.

The governance-velocity paradox Citadel sets out to solve is real. Getting the foundation right now, while it is still in preview and the patterns are malleable, is the right time to start.

Final note: This post reflects a hands-on deployment performed in June 2026. Given the pace of change in this space, verify all CLI commands, parameter schemas, and model versions against current documentation before applying them in your own environment.

Anatomy of an Agent Loop in Azure Logic Apps

Part 2 of 7 in the Logic Apps Agent Loop series

Part 1 explained why the Azure Logic Apps agent loop is a different design paradigm from conventional workflow automation. This post gets hands-on with the anatomy of that loop. We will look at the four building blocks that make up every agent loop trigger, instructions, connected model, and tools, and walk through how to wire them together in a Standard logic app.

By the end of this post you will have a working autonomous agent that accepts a prompt from a trigger, reasons over it using Azure OpenAI, invokes a connector action as a tool, and returns a result. The run history will show you exactly how the loop iterated.

The Azure Logic Apps agent loop: four building blocks

Before opening the designer, it helps to have a clear mental model of what you are assembling. Every Azure Logic Apps agent loop consists of four parts.

Trigger

The trigger starts the workflow, exactly as it does in any nonagentic Logic Apps workflow. For an autonomous agent, this can be any supported trigger an HTTP request, a timer, a Service Bus message, a new email, or anything else in the connector library. The trigger’s output becomes the initial input to the agent: the prompt or data the model will reason over.

Instructions

Instructions are the system prompt for the agent. You provide them as a block of natural language text in the agent action’s configuration pane. They define the agent’s role, what it can and cannot do, how it should respond, and any constraints it should observe. A well-written instructions block is the single most important factor in how well the agent performs. Think of it as the job description you hand to the model at the start of every run.

Connected model

The agent needs a language model to reason with. In Standard Logic Apps, you connect the agent to an Azure OpenAI Service resource and specify the model deployment to use — typically a GPT-4o deployment. The agent sends the instructions, the trigger input, and the results of any tool calls to the model at each iteration of the loop. The model’s response tells the agent what to do next.

Tools

A tool is a sequence of one or more connector actions that the agent can choose to invoke. You build tools directly in the Logic Apps designer by adding actions from the connector gallery inside the agent action. Each tool gets a name and a description — the model uses these to decide which tool to call and when. A single agent can have multiple tools. An agent with no tools can still respond to prompts using the model’s built-in knowledge, but it cannot take action on external systems.

The diagram below shows how these four parts fit together inside a single agent loop execution.

Building your first agent loop in Azure Logic Apps

The demo for this post is deliberately simple: an agent that receives a topic via an HTTP trigger, uses Azure OpenAI to generate a summary, and returns the result to the caller. One trigger, one model, one tool is enough to see all four building blocks in action and to read a meaningful run history.

Prerequisites

  • A Standard logic app resource deployed in Azure
  • An Azure OpenAI Service resource with a GPT-4o model deployment
  • Contributor access to both resources

Step 1: Create the workflow

In the Azure portal, open your Standard logic app and select Workflows from the sidebar. Choose Add, then select Autonomous Agents as the workflow type. Give the workflow a name and select Stateful. Logic Apps creates a new workflow with an empty agent action already in place.

Step 2: Configure the trigger

The autonomous agent workflow template starts with a When a HTTP request is received trigger by default. Leave the method as POST. In the request body JSON schema, add a single property: topic of type string. This is the input the agent will work with.

Step 3: Write the instructions

Select the agent action in the designer to open its configuration pane. On the Parameters tab, find the Instructions field. Enter something like the following:

You are a research assistant. When given a topic, use the available tools to retrieve relevant information and return a concise summary of no more than three sentences. Always cite your source.

Keep instructions specific and bounded. Vague instructions produce unpredictable behaviour. The model will take the instructions literally, so precision matters.

Step 4: Connect the model

Still on the Parameters tab, select Add connection under the model configuration section. Choose Azure OpenAI Service, select your resource, and choose your GPT-4o deployment. Logic Apps establishes the connection and stores it against the workflow.

Step 5: Add a tool

Inside the agent action, select Add a tool. This opens the connector gallery filtered to actions that can be used as tools. For this demo, add the HTTP action as a tool — name it search_web, give it the description “Retrieves content from a given URL”, and configure it to accept a URL as input. In a production scenario you would use Azure AI Search or a more capable connector here; the HTTP action keeps the demo self-contained.

Step 6: Save and run

Save the workflow. Use a REST client to POST a JSON body like {"topic": "Azure Logic Apps agent loop"} to the workflow’s trigger URL. The agent fires, the model reasons over the instructions and the topic, invokes the search tool, and returns a summary.

Reading the run history

he run history is where the Azure Logic Apps agent loop becomes visible. Open the workflow’s Run history and select the latest run. You will see the trigger, followed by the agent action. Expand the agent action and you will find each iteration of the loop shown as a numbered step: the model’s reasoning output, the tool call with its inputs and outputs, and the model’s decision on whether to loop again or return a final answer.

This is the key difference from a nonagentic run history. In a conventional workflow, the run history shows a flat list of actions. In an agent loop, it shows a nested, iterative structure the model’s chain of thought made visible.

For a simple prompt, you may see a single iteration. For a more complex task involving multiple tool calls, you will see the loop unfold across three, five, or more steps. Each step shows exactly what the model decided and why.

Standard versus Consumption: model connections

In Standard logic apps, you configure the model connection yourself — selecting an Azure OpenAI Service resource and specifying the deployment. This gives you full control over which model version you use, where it is hosted, and how it is secured via Managed Identity.

In Consumption logic apps (currently in public preview), the model connection is handled via Microsoft Foundry and the configuration is more constrained. For any production workload, Standard remains the right choice.

What comes next

The agent in this post is autonomous it runs without human interaction, triggered by an HTTP call and returning a result when done. That covers a wide range of integration scenarios, but not all of them. Some tasks require a back-and-forth with a user: a support conversation, a guided data-entry flow, a multi-turn research session.

The next part will cover exactly that distinction, autonomous versus conversational agentic workflows, and walk through when to choose each pattern and what changes in the designer when you do.