gemini_image_generate
Create images from text descriptions using Gemini's image models. Supports multiple sizes, aspect ratios, and reference images for guided generation.
Instructions
Generate image(s) from a text prompt with a Gemini image model (Nano Banana / Nano Banana Pro). If the result will likely be refined iteratively, prefer gemini_interact (multi-turn) as the entry point.
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| seed | No | Seed for reproducible generation; random if omitted | |
| async | No | Run in the background and return a job_id immediately instead of the image, so a long (Pro/4K) generation cannot hit the host tools/call timeout (-32001). Poll gemini_get_result with the job_id to fetch the result (jobs are per-process and expire ~10 min after completion). | |
| count | No | Number of independent images (default 1) | |
| model | No | Model id override (default: server default; see gemini_list_models). gemini-3.1-flash-image (Nano Banana 2) is the versatile generalist workhorse — balances speed with state-of-the-art 4K generation, world knowledge, and reliable text rendering; excels at multi-reference-image processing and consistency. gemini-3-pro-image (Nano Banana Pro) is the premium choice for the most complex visual tasks — highest world knowledge, advanced localization, accurate brand consistency, precision creative control. gemini-3.1-flash-lite-image (Nano Banana 2 Lite) is the fastest/cheapest for simple tasks (1K only, no search grounding). | |
| images | No | Paths to reference input images (image-conditioned generation) | |
| inline | No | Return base64 images inline instead of writing to disk | |
| prompt | Yes | Text prompt describing the image | |
| confirm | No | Must be true to proceed. Without this, the tool returns a preview. | |
| filename | No | Base filename for the output image (extension stripped; default: slugified prompt) | |
| video_url | No | Public YouTube URL (or a previously uploaded Files API uri) as a video reference (video→image; use a Flash model e.g. gemini-3.1-flash-image) | |
| image_size | No | Output resolution (512 = 0.5K, Flash-only) | |
| images_url | No | Reference images as public https URLs — the SERVER downloads them, so no image bytes travel through the conversation. Preferred over images_base64, which costs ~14k tokens per photo and breaks if a file read was truncated. Max 15MB each; must be a directly-linked image (Content-Type image/*). | |
| output_dir | No | Directory to write images to (default: $GEMINI_OUTPUT_DIR or cwd) | |
| timeout_ms | No | Upstream request timeout in ms for this call (default: $GEMINI_TIMEOUT_MS, else 60000 — or 120000 when image_size is 4K, which routinely runs past 60s) | |
| video_path | No | Path to a local video file — uploaded to the Gemini Files API (~48h retention, 2 GB max) and used as the video reference. Alternative to video_url. | |
| aspect_ratio | No | Output aspect ratio | |
| google_search | No | Ground the image in live Google Search results (current events, weather, data) | |
| images_base64 | No | Reference images as base64 strings or data URIs. Last resort: prefer images_url or images_file_uris, which keep image bytes out of the conversation | |
| from_clipboard | No | Use the image currently on the macOS system clipboard as an input (downscaled to JPEG) | |
| thinking_level | No | Reasoning depth (Gemini 3 models); higher can help complex/structural edits | |
| idempotency_key | No | Opaque idempotency key: a repeat call with the same key returns the recorded result (reused: true) instead of billing a new generation. Set it when retrying after a host timeout (-32001) to avoid a duplicate charge. | |
| images_file_uris | No | Reference images by Gemini Files API reference ("files/<id>", or the full uri) from gemini_upload_file or POST /upload. Upload once, then reference it across as many calls as you like — no bytes are re-sent and none enter the conversation. Files are retained ~48h, after which the reference stops resolving. |