Generation & references
Place image bytes and understand the boundary of MCP media editing.
The batch_design operation create_image accepts a data:image/...;base64,... URI or raw base64 for an encoded PNG, JPEG, WebP, or GIF. You can provide width or height to preserve aspect ratio, and meta to record provenance. Fanta ingests it as an asset under assets/images/ on save.
create_image does not fetch http(s) URLs. Use import_image with exactly one of path (absolute or project relative), HTTP(S) url, or base64 source to save an image into the project's Assets panel. It returns an asset ID and saved path but does not create a canvas layer. A URL import has a download timeout and image-size limit. Use a separate placement workflow or valid FNX source edit when the design needs that asset on canvas.
set_fill can replace a frame or shape's paint stack with an image paint. Its source is encoded PNG/JPEG/WebP/GIF bytes, and fit can be fill, fit, stretch, or tile. It ingests the bytes as an asset in the same undoable batch. A style read may show an existing image's asset ID; that ID is not the source argument for set_fill.
prepare_design_asset accepts kind: "image" or "svg", a prompt, and optional preferred_model. It opens the existing generation composer for the user to review; it does not submit a request or spend credits. The external MCP surface has no direct generate_image or generate_media tool. Some toolbar AI commands also open drafts that require the user to send them.
Inspect imported or placed media on canvas and with get_screenshot. See the known issues for alpha limitations.