Tool: BOX_UPLOAD_FILE Log ID: log_Q9bj8GcM8kDd Date: March 2, 2026 Description: The BOX_UPLOAD_FILE tool consistently returns a server-side error when called with a valid base64-encoded file and correct attributes. The Box connection itself is active and authenticated — other Box tools (e.g., BOX_LIST_ITEMS_IN_FOLDER) work correctly with the same connected account. Error response: json { "data": { "message": "'NoneType' object is not subscriptable", "status_code": null }, "successful": false, "error": "'NoneType' object is not subscriptable", "log_id": "log_Q9bj8GcM8kDd" } Request payload used: json { "connected_account_id": "ca_YZZl7GyCCB8u", "arguments": { "attributes": { "name": "laika-box-test.txt", "parent": { "id": "0" } }, "file": { "name": "laika-box-test.txt", "content": "" } } } What works: BOX_LIST_ITEMS_IN_FOLDER — returns results successfully ✅ Box connection status: ACTIVE ✅ What doesn't work: BOX_UPLOAD_FILE — NoneType error ❌ BOX_CREATE_UPLOAD_SESSION — returns 405 Method Not Allowed (appears to be hitting the wrong endpoint — api.box.com instead of upload.box.com) ❌ Hypothesis: The error likely occurs in how the Composio proxy handles the format: "binary" parameter type on the file field — it may not be correctly deserializing/passing the base64 content through to the Box upload API.

Hey @John, I just checked your logId and looks like you are using an older version of the tool, could you try using the latest version(

20260225_02

) and lmk if it's working? Docs for ref: https://docs.composio.dev/docs/tools-direct/toolkit-versioning.

Oh thank you, that did work!