An AI coding agent can inspect a function without knowing which system owns it or which external service constrains its behavior. A C4 model supplies that missing scope. It is most useful when the agent retrieves the relevant architecture before proposing a change and checks its assumptions against implementation evidence.
Give the agent a concrete question
Use the e-commerce model below. Ask what changes when the payment provider introduces a new authorization contract. The useful answer names the affected boundary, the payment-facing service, its callers and the evidence needed before editing code.
The model is a starting point for investigation, not proof that the running system matches the documentation. A missing relationship may mean the model is incomplete. Have the agent report uncertainty instead of filling gaps with plausible architecture.
Try this review prompt
Read the architecture for the checkout system before proposing code changes.
Identify the payment provider, its callers and the owning container.
List the relevant model element IDs and relationships.
Inspect repository evidence for each dependency you intend to change.
Separate observed facts from assumptions and proposed design changes.
Describe the impact on context, container and component views.
Present a proposed model update for review before applying it.
Download a portable checkout model for a small practice exercise. It is synthetic teaching data, not a claim about your repository.
Download the full review prompt with target placeholders and a structured response format. In the checkout example, a useful proposal should identify the adapter-facing contract and the tests needed to verify it. It should not invent repository paths or claim that every caller must change before inspecting the code.
Connect architecture through MCP
The UXXU MCP setup guide describes the organization-scoped endpoint and API-key authentication. A compatible client can inspect architecture and use the tools allowed by the key’s permissions. Start by asking it to list the available projects and read the relevant diagram; confirm the target before making updates.
Do not put a real API key into a shared prompt, model description or public embed. Keep credentials in the client’s secret configuration. Access to a diagram should not become accidental access to a different organization.
Review the architecture change with the code change
When an implementation adds a new dependency, update the shared element and relationship rather than drawing a second copy for one audience. Verify the related views after the change. When only a class implementation changes and the contract is preserved, the higher-level architecture may not need editing.
Use the UXXU C4 model tool for the human review and the maintenance checklist to make that review repeatable.