# devstral-2512

Calls to the model devstral-2512 on Mistral stopped working on July 31, 2026.

Mistral retired model devstral-2512 on July 31, 2026. Calls specifying this model fail since that date. The change was announced on May 22, 2026.

## The error Mistral returns once devstral-2512 is gone

HTTP 400

```json
{"object":"error","message":"Invalid model: devstral-2512","type":"invalid_model","param":null,"code":"1500"}
```

## What to use instead

Mistral recommends migrating to Mistral Medium 3.5.

- API: Mistral (api.mistral.ai)
- Model: devstral-2512
- Released: December 9, 2025 (models.dev)
- Kind: Model retirement
- Announced: May 22, 2026
- Takes effect: July 31, 2026
- Calls after that day: fail
- Calls it hits: `model devstral-2512`
- Source: [Lifecycle page](https://docs.mistral.ai/getting-started/models/models_overview/)
- Verified: November 6, 2026, against Mistral's own pages
- Page: https://www.okapi.bot/models/mistral/devstral-2512/

Okapi finds the calls this change hits in your repo and opens the pull request with the fix: https://github.com/apps/okapi-agent