Can I fix this without downgrading OpenClaw?

As of now, downgrading is the only confirmed fix. The issue is a regression in newer OpenClaw versions, and the exact fix from Mistral's side isn't public. Keep an eye on the OpenClaw GitHub issues for updates.

What does '422 status code (no body)' mean?

A 422 error means the server understood your request but couldn't process it due to semantic errors in the request. 'No body' means the server didn't provide any specific details about what was wrong.

Does this affect other Mistral models like Codestral?

Yes, users have reported it affects other models like `codestral-latest` as well, indicating a broader compatibility issue with the Mistral provider in affected OpenClaw versions.

Fix Mistral 422 Status Code (no body) Error in OpenClaw

TL;DR — Quick Fix

The `mistral` provider in OpenClaw v2026.3.8 and later returns a `422 status code (no body)` error. Downgrade to v2026.3.7 or earlier.

Run Diagnostics

Next Step

Fix now, then reduce repeat incidents

If this issue keeps coming back, validate your setup in Doctor first, then harden your config.

Open Doctor Harden Config

Error Signal

embedded run agent end: ... isError=true error=422 status code (no body)

What's Happening

You're seeing a 422 status code (no body) error when using the Mistral provider in OpenClaw, specifically after version 2026.3.7. Your direct API calls to Mistral work fine, but OpenClaw fails. This started around version 2026.3.8.

The Fix

The confirmed fix from the community is to downgrade your OpenClaw installation. Several users reported that versions 2026.3.7 or 2026.2.25 work correctly. You'll need to revert to one of these older versions until a fix is merged and released.

For example, if you installed via Docker:

docker pull openclaw/openclaw:2026.3.7

Or if you built from source, checkout an older tag:

git checkout v2026.3.7

Why This Occurs

This looks like a regression introduced in OpenClaw 2026.3.8. The exact cause isn't detailed, but Mistral's API might be rejecting the request format OpenClaw is sending in newer versions. The 422 status code typically means 'Unprocessable Entity', and the lack of a response body means Mistral isn't giving a specific reason for the rejection.

Prevention

Be cautious when upgrading OpenClaw, especially to patch versions if you rely on specific provider integrations. Watch the OpenClaw GitHub releases for fixes related to Mistral. You can also try running npx clawaid in your project to check your overall config health, though this specific issue is a provider compatibility bug.

As a temporary workaround, you could try using Mistral via OpenRouter if that's an option for you.

Last Updated: March 2026

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