Gemini MCP server

gemini-mcp

MCP server for Google Gemini media generation. Exposes thirteen tools to Claude over stdio: list available models, generate/edit/compose images, generate a consistent set of images from a master prompt, multi-turn image refinement (Interactions API), video generation (omni), music generation (Lyria), an async result poll for long generations, and Files API upload/list/delete for reusable image references. Output is written to disk by default (path returned) or returned inline as base64. Built on the Gemini v1beta API (generativelanguage.googleapis.com) using the Nano Banana / Nano Banana Pro (images), omni (video), and Lyria (music) model families.

Developed and maintained by AI (Claude Code).

Environment Variables

Long generations and client timeouts

4K / Pro-model generations can outrun an MCP host's own tools/call timeout (error -32001). The server sends notifications/progress heartbeats so hosts that reset their timeout on progress wait it out. If the host still gives up, the server-side generation usually completes anyway: the image is written to the output dir, geminiinteract also writes an .json sidecar recording the interactionid, and continue_last: true resumes the interaction the lost response belonged to.

When a chained call 404s

A 404 on a request carrying previousinteractionid is not proof the chain expired. The only 404 body observed live is generic — "Requested entity was not found." — and never names which entity. An unknown or renamed model id, and an expired Files API files/… uri (~48h TTL), return exactly the same thing. So the server no longer asserts a cause it can't establish: the upstream text is surfaced verbatim, and gemini_interact runs an experiment to find out which it was.

Most often the id isn't missing at all — it just isn't visible yet. The interactions store is eventually consistent, and a freshly created id can 404 while the same id resolves fine minutes later; heavy turns (4K, Pro, thinkinglevel: high) are the likeliest to hit it, which is exactly the turn you most want to chain from. So a chained 404 is retried with exponential backoff for up to 120s (GEMINICHAINRETRYMS) before anything is declared broken. The 404 generates nothing and isn't billed, so the wait costs only time.

After that budget is spent, the tool looks up that id's sidecar, re-attaches the image it produced, and re-issues the request without the chain:

Shortened. The full README is on GitHub.