# Chat models return 503 service error when /v1/chat requests omit message and chat\_history while providing tool\_results

- Provider: [Cohere](https://down.guide/providers/cohere)
- Confidence: Confirmed
- Impact: Operational
- lasted 37m
- started 2025-10-18 21:46 UTC
- id: DWN-0033eacd0f
- Official page: https://status.cohere.com/incidents/01K7WMKZTGGPADA69MEAE9P4TY

## Updates from Cohere
### 2025-10-18 21:46 UTC: identified
🛠️ We have identified the root cause of the incident, and are working diligently to fix.

### 2025-10-18 22:23 UTC: resolved
🎉 The issue has been resolved and we are back to normal.

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