# Dependency Slimming: pydantic-ai → pydantic-ai-slim

**Date**: 2025-12-13
**Version**: Post v1.2.0

## Change

Switched from `pydantic-ai` to `pydantic-ai-slim[openai]` to reduce container image size.

### Before
```
pydantic-ai>=1.27,<1.28
```

This installs SDKs for ALL LLM providers:
- anthropic
- boto3 + botocore (AWS Bedrock)
- cohere
- google-genai + google-auth
- groq
- huggingface-hub

Total packages: ~158

### After
```
pydantic-ai-slim[openai]>=1.27,<1.28
```

Only installs the OpenAI-compatible SDK. Ollama works through this interface.

Expected packages: ~80-90 (significant reduction)

## Why This Works

Tatlock uses Ollama exclusively, which implements the OpenAI-compatible API. The code uses:
```python
from pydantic_ai.models.openai import OpenAIChatModel
from pydantic_ai.providers.ollama import OllamaProvider

model = OpenAIChatModel(
    model_name=config.OLLAMA_DEFAULT_MODEL,
    provider=OllamaProvider(base_url=f"{config.OLLAMA_HOST}/v1")
)
```

This pattern only requires the `openai` extra, not the full pydantic-ai package.

## Rollback Instructions

If this change breaks things:

1. Revert requirements.txt:
```diff
- pydantic-ai-slim[openai]>=1.27,<1.28
+ pydantic-ai>=1.27,<1.28
```

2. Reinstall dependencies:
```bash
pip install -r requirements.txt
```

3. Delete this file once confirmed stable.

## Testing Checklist

- [ ] Unit tests pass
- [ ] Integration tests pass (with Ollama running)
- [ ] Wakeup script e2e test passes
- [ ] Container builds successfully
- [ ] Container runs correctly