Microsoft put Azure API Management's AI Gateway tier into public preview on July 27, available in East US 2 and Sweden Central at no cost while pricing is determined. The tier is a purpose-built resource whose control plane is organized around models, MCP servers, and tools rather than APIs — a structural departure from the policy-layering approach of the classic and v2 tiers, which retain their existing AI gateway capabilities unchanged.
The model federation layer covers the multi-cloud reality most enterprise fleets already live in. The preview publishes Foundry-hosted models including OpenAI, Anthropic, and Mistral alongside models in AWS Bedrock, Google Vertex AI, and OpenAI direct. All OpenAI-compatible providers share one endpoint path; the gateway routes on an exact match of the model field, so each published model requires a unique name. Anthropic runs through a custom provider with Messages API passthrough. A gateway provisions in about a minute with no scale units to plan.
| Provider | Hosting Platform | Endpoint Protocol | Routing Mechanism |
|---|---|---|---|
| OpenAI | Azure Foundry | OpenAI-compatible | Exact match on model field; unique name required |
| Anthropic | Azure Foundry | Custom provider — Messages API passthrough | Exact match on model field; unique name required |
| Mistral | Azure Foundry | OpenAI-compatible | Exact match on model field; unique name required |
| AWS Bedrock models | AWS Bedrock | OpenAI-compatible | Exact match on model field; unique name required |
| Google Vertex AI models | Google Vertex AI | OpenAI-compatible | Exact match on model field; unique name required |
| OpenAI (direct) | OpenAI Direct | OpenAI-compatible | Exact match on model field; unique name required |
| Provider | Hosting Platform | API Protocol | Routing / Notes |
|---|---|---|---|
| OpenAI | Azure AI Foundry | OpenAI-compatible | Shared endpoint; routes on exact match of model field |
| Anthropic | Azure AI Foundry | Messages API passthrough | Custom provider; separate API path |
| Mistral | Azure AI Foundry | OpenAI-compatible | Shared endpoint; routes on exact match of model field |
| Models on AWS Bedrock | AWS Bedrock | OpenAI-compatible | Shared endpoint; routes on exact match of model field |
| Models on Google Vertex AI | Google Vertex AI | OpenAI-compatible | Shared endpoint; routes on exact match of model field |
| OpenAI (direct) | OpenAI | OpenAI-compatible | Shared endpoint; each published model requires a unique name |
Tool federation extends the same pattern to the MCP layer. Teams can expose an existing MCP server over SSE or Streamable HTTP, convert REST API operations into an MCP server by uploading an OpenAPI spec, or draw on more than 1,400 connector-backed tools from the Power Platform and Logic Apps library without hosting a server. Multiple MCP servers federate behind a single endpoint, so an agent connects once and resolves tools across all of them. Per-backend authentication supports API keys, OAuth 2.0 client credentials, managed identity, and mTLS.
| Exposure Method | Source / Transport | Server Hosting Required | Supported Auth Schemes |
|---|---|---|---|
| Expose existing MCP server | SSE or Streamable HTTP | Yes (customer-hosted) | API key, OAuth 2.0 client credentials, managed identity, mTLS |
| Convert REST API via OpenAPI spec | Uploaded OpenAPI spec → auto-generated MCP server | No | API key, OAuth 2.0 client credentials, managed identity, mTLS |
| Connector-backed tools (Power Platform / Logic Apps) | 1,400+ pre-built connectors | No | Managed by connector platform |
Governance is configured through policy cards in the portal as JSON properties rather than the XML expressions APIM veterans know. Cards cover request and token rate limits, token quotas, Azure AI Content Safety, and fallback to a secondary model. Policies apply per asset, making coverage for each model or MCP server explicit. Telemetry flows as OpenTelemetry token metrics with GenAI semantic conventions to Application Insights, Datadog, Splunk, Grafana Cloud, or any OTLP endpoint the customer controls. The resource runs in the customer's own subscription and Entra tenant.
| Category | Item | Notes |
|---|---|---|
| Policy Card | Request rate limit | Applied per asset (per model or MCP server) |
| Policy Card | Token rate limit | Applied per asset |
| Policy Card | Token quota | Applied per asset |
| Policy Card | Azure AI Content Safety | Applied per asset |
| Policy Card | Fallback to secondary model | Applied per asset; activates on primary failure |
| Telemetry | Application Insights | OpenTelemetry token metrics with GenAI semantic conventions |
| Telemetry | Datadog | OpenTelemetry token metrics with GenAI semantic conventions |
| Telemetry | Splunk | OpenTelemetry token metrics with GenAI semantic conventions |
| Telemetry | Grafana Cloud | OpenTelemetry token metrics with GenAI semantic conventions |
| Telemetry | Any OTLP endpoint | Customer-controlled destination |
| Category | Item | Detail |
|---|---|---|
| Policy card | Request rate limits | Per model or MCP server; configured as JSON in portal |
| Policy card | Token rate limits | Per model or MCP server; configured as JSON in portal |
| Policy card | Token quotas | Per model or MCP server; configured as JSON in portal |
| Policy card | Azure AI Content Safety | Per model or MCP server; configured as JSON in portal |
| Policy card | Model fallback | Fallback to a secondary model on failure |
| Telemetry | Application Insights | OpenTelemetry token metrics, GenAI semantic conventions |
| Telemetry | Datadog | OpenTelemetry / OTLP |
| Telemetry | Splunk | OpenTelemetry / OTLP |
| Telemetry | Grafana Cloud | OpenTelemetry / OTLP |
| Telemetry | Custom OTLP endpoint | Any customer-controlled OTLP destination |
The operating model splits platform ownership from team autonomy. A central group connects approved models and tools, sets guardrails, and retains the usage picture; application teams test assets in a built-in console and build against them without routing every change through the center. This works only if the access boundary holds. It does not hold the way APIM subscription scoping did: a runtime key is gateway-scoped, reaching every model and every tool published on that gateway. Microsoft's guidance is one key per application, but a leaked key's blast radius is the entire gateway rather than a single product. Teams that relied on APIM subscriptions to scope consumers to specific APIs must redesign that boundary.
Two unresolved questions from architects matter. Agent lifecycle coverage is the first: if an agent run ends without clean completion after producing useful work, it is unclear whether the output is preserved for auditable review or whether the gateway retries the run from scratch. The distinction matters for stateful agent pipelines where idempotency is not guaranteed. The second is coexistence: organizations that built AI gateway configurations on Premium or Standard v2 have no published guidance on whether those investments carry across, run alongside, or migrate into the new tier. Microsoft's documentation describes the AI Gateway tier as an extension of the existing gateway, but the portal and control plane are structurally separate.
Preview posture requires careful reading before planning an onboarding schedule. There is no SLA. APIs, telemetry, limits, regions, and pricing can all change before GA. Specific throughput and quota caps are unpublished. Pricing is not yet announced, which leaves the cost-governance argument—the one most cited as the tier's practical value—as the least settled part of the release.
The architectural takeaway: the AI Gateway tier solves the control-plane consolidation problem for teams fronting five or more model providers, but key-scoping and coexistence gaps make it a workbench deployment rather than a production control plane until Microsoft ships quota granularity and migration guidance.