Question 1

What is Viaduct?

Accepted Answer

Viaduct is a C4 architecture modeling tool that connects system, container, component, and code diagrams in a single model, and provides a hosted MCP server for AI coding agents.

Question 2

How does the MCP server work?

Accepted Answer

You get a personal token that connects MCP-compatible clients like Cursor or Claude Code to your architecture model, allowing agents to query services, endpoints, documentation, and diagrams.

Question 3

Is Viaduct free?

Accepted Answer

The quick start editor is available without an account and sends nothing anywhere, but ongoing team usage likely follows a freemium model with paid plans for advanced features.

Question 4

Can I import an existing OpenAPI spec?

Accepted Answer

Yes, Viaduct supports importing OpenAPI documents to populate container endpoints, and can export them back as files.

Question 5

What are change sets?

Accepted Answer

Change sets are structured diffs of architecture changes, similar to code review, so you can approve or reject modifications proposed by your team or an AI agent.

Viaduct

Alternatives

GitHub Copilot

Cursor

Replit AI

v0 by Vercel

Bolt.new

Codeium