Reported by @rare jacinth
Bug Report: Android ChatGPT app sends string placeholder for MCP image file param, causing INVALID_PARAMETERS
`Steps to Reproduce`
- Open ChatGPT Android app (version
ChatGPT/1.2025.350). - Select a Connector that expect an image object (MCP tool).
- Attach an image file.
- Prompt: “Add contour to image.” or “Use XX Connector on the attached image. Do not generate a new image.”
- Approve the tool call when prompted.
`Expected Result`
The tool receives image as an object with { download_url, file_id }, passes schema validation, and the MCP server processes the image.
`Actual Result`
The approval payload shows {"image":"attached_image"} or {"image":"image0"} or {"image":"attachment://image"} (string placeholder). The tool call fails schema validation with:
reason: INVALID_PARAMETERSExpected type ['object'], got str
ChatGPT then falls back to native image generation instead of the MCP tool.
PS: the same interaction works perfectly on Web/iOS but not on Android.
`Environment`
ChatGPT Android app (v 1.2025.350)