# babbage-002

Calls to the model babbage-002 on OpenAI stopped working on September 28, 2026.

On September 28, 2026, the model babbage-002 was shut down and stopped working. API calls specifying model babbage-002 fail since that day.

## The error OpenAI returns once babbage-002 is gone

HTTP 404

```json
{"error":{"message":"The model `babbage-002` has been deprecated, learn more here: https://platform.openai.com/docs/deprecations","type":"invalid_request_error","param":null,"code":"model_not_found"}}
```

## What to use instead

Move to the recommended replacement gpt-5.6-terra. Because gpt-5.6-terra is not served on /v1/completions, moving to it requires more than updating the model id: calls must shift to Chat Completions (/v1/chat/completions) or the Responses API (/v1/responses), adapting the prompt string into messages or input.

gpt-5.6-terra is not served on /v1/completions. Move the call to Chat Completions (/v1/chat/completions) or the Responses API (/v1/responses): the prompt string becomes messages or input.

- API: OpenAI (api.openai.com)
- Model: babbage-002
- Kind: Model retirement
- Takes effect: September 28, 2026
- Calls after that day: fail
- Calls it hits: `model babbage-002`
- Source: [Deprecations page](https://developers.openai.com/api/docs/deprecations)
- Verified: November 6, 2026, against OpenAI's own pages
- Page: https://www.okapi.bot/models/openai/babbage-002/

## OpenAI's words

> Shutdown date: 2026-09-28; Model / system: babbage-002; Recommended replacement: gpt-5.6-terra

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