Elevated errors: Invalid `signature` in `thinking` block

Timeline

Started: 2026-01-23T05:09:39.604Z

Updated: 2026-01-23T07:47:45.193Z

Resolved: 2026-01-23T07:47:45.178Z

Impact scope

Official sources

Provider: anthropic

Updates

• resolved

  This issue is resolved for new requests. However, for responses from one platform received between 2026-01-23 00:00 UTC - 2026-01-23 08:00 UTC that are subsequently included in requests sent to a different platform, there may still be errors.

  2026-01-23T07:47:45.178Z

• monitoring

  A fix has been implemented and we are monitoring the results.

  2026-01-23T07:32:15.476Z

• identified

  We are continuing to work on a fix for this issue.

  2026-01-23T06:24:09.882Z

• identified

  A mitigation is to _not_ mix Claude API traffic between Bedrock, Vertex, and api.anthropic.com. Each platform is fully operational independently.

  2026-01-23T05:22:32.529Z

• identified

  We are continuing to work on a fix for this issue.

  2026-01-23T05:12:47.205Z

• identified

  We are continuing to work on a fix for this issue.

  2026-01-23T05:10:43.895Z

• identified

  The issue has been identified and fix is being implemented.

  2026-01-23T05:09:39.660Z