Cloudviz API vs Lucid API + MCP

Cloudviz API

Diagrams come from the live AWS account through a read-only cross-account role with a per-customer external ID. AWS only, and API access starts at the $49 a month Team plan.

Lucid API + MCP

OAuth 2.0 scopes with :readonly variants, and audit log endpoints in the REST API. No public changelog for the API or the MCP server.

Cloudviz API

1. Call GET /aws/accounts/ first to get the Cloudviz account ID, then request /aws/accounts/{account-id}/{region}/{format}
2. On a 202, wait and repeat the same GET until the diagram is ready
3. Ask for jsonSnapshot or jsonDiagram (there is no plain json format) when the agent has to reason over resources
4. Use a read-only key unless the agent has to add, change or delete AWS accounts

Lucid API + MCP

1. Always send Lucid-Api-Version: 1, or prefix the path with /v1
2. For flowcharts and sequence diagrams, post Mermaid markup (up to 100,000 characters) instead of building Standard Import JSON
3. Request :readonly scopes when the agent only reads documents
4. On 429, wait 60 seconds or back off. Create Mermaid Diagram allows 60 calls a minute
5. Sharing and embed endpoints need an OAuth token. An API key won't work there