# text-bison

Calls to the model text-bison on Vertex AI stopped working on April 21, 2025.

## The error Vertex AI returns once text-bison is gone

HTTP 404

```json
{"error":{"code":404,"message":"Publisher model `projects/{project}/locations/{region}/publishers/google/models/text-bison` was not found or your project does not have access to it. Ensure you are using a valid model name and that the model is available in the specified region.","status":"NOT_FOUND"}}
```

## What to use instead

Move to gemini-3.8-flash. gemini-2.5-flash-lite, named first, stopped working on 2026-10-20.

- API: Vertex AI (aiplatform.googleapis.com)
- Model: text-bison
- Kind: Model retirement
- Takes effect: April 21, 2025
- Calls after that day: fail
- Calls it hits: `model text-bison`
- Source: [Deprecations page](https://cloud.google.com/vertex-ai/generative-ai/docs/learn/model-versions)
- Verified: November 6, 2026, against Vertex AI's own pages
- Page: https://www.okapi.bot/models/vertex-ai/text-bison/

## Vertex AI's words

> Model ID: text-bison; Release date: May 2023; Retirement date: April 21, 2025; Recommended upgrade: gemini-2.5-flash-lite

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