# 400 errors on JSON uploads need clearer error messages **URL:** \ **Category:** Feature Requests\ **Created:** [May 7, 2026, 4:19pm UTC](https://community.retellai.com/t/400-errors-on-json-uploads-need-clearer-error-messages/2617 "2026-05-07T16:19:14Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![mendyezagui](https://yyz2.discourse-cdn.com/flex008/user_avatar/community.retellai.com/mendyezagui/32/1762_2.png) [@mendyezagui](https://community.retellai.com/u/mendyezagui)\ **Post date:** [May 7, 2026, 4:19pm UTC](https://community.retellai.com/t/400-errors-on-json-uploads-need-clearer-error-messages/2617/1 "2026-05-07T16:19:14Z")
When uploading JSON for agent configs or test definitions, validation failures return a generic 400 with little context. Figuring out what actually broke turns into a binary search through the payload — slow and painful, especially with large configs. What would help: 1. **Field-level error messages** — name the offending key, the value, and the expected type/format (e.g. `"tools[2].parameters.required must be an array of strings, received string"`) 2. **Multiple errors per response** when there are several issues, so we fix everything at once instead of one round-trip per error 3. **Schema reference link** in the error response pointing to the relevant docs section This is standard practice for any API that accepts structured input — the current behavior forces us to guess and re-upload