What an AI application is

Strip away the demos and an AI application is a normal enterprise system with three new parts: a model you do not control, retrieval that feeds it context, and tools it is allowed to call. Everything around those three is engineering you already know: networks, databases, identity, integration, operations and cost.

That is why the map above has lenses. Pick one and the same system turns into a networking problem, a data problem or an identity problem, with the components that matter for that discipline lit up.

The shape that survives production

  • Edge and API gateway own the way in: TLS, WAF, authentication and rate limits, with origins that accept traffic only from them.
  • Agent decides what happens next. In most systems it is a supervisor with a small set of specialist workers, explicit stop conditions and checkpoints, so a run can resume after a crash.
  • LLM gateway is the only way out to a model: routing, budgets, redaction, caching and one place to trace every call.
  • Retrieval supplies the knowledge the model was never trained on, filtered at query time by who is asking.
  • Ingestion keeps that knowledge fresh from the systems that own it, and copies their permissions onto every chunk.
  • Tools are typed MCP servers with explicit permissions in front of real enterprise APIs. Writes carry idempotency keys, and the risky ones wait for a person.

Where teams get hurt

  • Identity stops at the web app, so the agent calls tools as a shared service account and every user can reach whatever that account can.
  • Retrieval leaks across teams, because permissions were not copied with the chunks or were not applied at query time.
  • Observability arrives after the first incident, so nobody can say which retrieved text or tool call produced a bad answer.
  • Evaluation lives in a spreadsheet instead of the release path, so a prompt change ships with no regression check.
  • Retries meet side effects without idempotency keys, and an approval or a refund happens twice.

The guides attached to each component take these in order.

Where platforms meet

Every hop between two platforms is a seam. Each one needs identity federation (whose token crosses?), a private network path (no public egress), and a data decision (what leaves, in which region, logged where).

Azure and Databricks

Identity
Use Entra ID as the identity provider for both. Provision users and groups into Databricks with SCIM, map the Foundry managed identity to a Databricks service principal, and pass the user's token (audience: the Azure Databricks resource) wherever row-level access matters.
Network
Keep the hop private: Private Link to the workspace, and for serverless compute a network connectivity configuration (NCC) with private endpoints back to your storage and services. Turn off public network access on both sides.
Data
Decide what crosses. Send retrieved chunks and citations rather than tables. Keep both sides in one region for residency, and log the call on both (Log Analytics and Databricks system tables) so an audit can join them on a request ID.

Read moreYour agent should not be a superuserRelevant data can still be data the user may not seeShared agent memory is an access-control problem

Open source and Azure

Identity
Federate your OIDC provider with Entra ID, or use workload identity federation so self-hosted services get short-lived Entra tokens without stored secrets.
Network
Reach Azure services through private endpoints from your VNet, or over ExpressRoute or VPN from on-premises. Avoid public endpoints with API keys.
Data
Prompts and completions leave your boundary at this hop: check the region, retention and abuse-monitoring settings of the Azure model deployment, and log the request ID on your side.

Read moreWhat an AI gateway actually costs to runWhere your MCP server runs is a production decision

Open source and Databricks

Identity
Authenticate as a Databricks service principal with OAuth machine-to-machine tokens rather than personal access tokens, and federate users through the same IdP the workspace trusts.
Network
Front-end Private Link to the workspace, with IP access lists as the fallback where Private Link is not available.
Data
Query through SQL warehouses or Vector Search endpoints instead of copying tables out, so Unity Catalog lineage records who read what.

Read moreA vector store is infrastructure, not magic memoryA stale answer is a wrong answer

Every connection that can cross platforms (22)

Node by node

Your network

Web App

Frontend3 linked

Identity

SSO · OBO2 linked

API Gateway

AuthN · limits4 linked

Secrets

Vault · KMS1 linked

Agent

Orchestration40 linked

LLM Gateway

Route · budget11 linked

Observability

Traces · evals19 linked

Tools

MCP servers20 linked

Human review

Approval queue4 linked

Private subnet

Ingestion

Chunk · embed12 linked

Vector Index

Embeddings · hybrid7 linked

Retrieval

Hybrid · rerank29 linked

Memory

Session · long-term7 linked

On this map