It depends on the plan. Every diagram is stored as native draw.io XML, so you can keep editing it with prompts on either plan. Paid gets that XML back in every reply and as a .drawio export; open it at app.diagrams.net. Free gets an SVG with a watermark, and replies carry xml: null with a link to that SVG.
Yes, with no usage limit. Free costs 0andmakesunlimiteddiagramsandeditsthroughtheAPI,MCPserverandSDKs.Paidis0 and makes unlimited diagrams and edits through the API, MCP server and SDKs. Paid is 20 a month or $120 a year, and adds two things: no watermark, and the draw.io file. See Plans & pricing.
Use the MCP server to give an AI agent (Claude, Cursor) the ability to make diagrams in-loop. Use an SDK (Python or TypeScript) for app and CI code. Use the REST API directly from any other language.
dgz_test_ keys have a lower rate limit. They still run real generations on your account, so they are not a sandbox. See Authentication.
AWS, Azure, GCP, and general architecture. Call Meta at runtime for the authoritative list of providers, diagram types, and export formats.
Store it in a secret manager, use it server-side only, and never commit it. Keys are shown once, stored only as a hash, and can be revoked instantly. See Security.
You get a consistent envelope with a code, message, and request_id. See Errors. Quote the request_id to support.
No. Bring your own key (BYO) was removed on 9 October 2026, and stored provider keys were deleted. Every request runs on our models, on both plans.
Yes, per key and per IP, and that is the only limit. A 429 means back off and retry. See Rate limits.