# OpenAI GPT Models Feedback for Hermes Agent

**Source reference:** Official docs, community discussions, blog posts

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## Supported Models

Hermes Agent supports OpenAI models including:
- GPT-4o / GPT-4o-mini
- GPT-5 series (via API)
- o1 / o3 (reasoning models)
- Codex models (with special OAuth handling)

---

## Codex Integration

**Special Feature:** When using Anthropic OAuth through `hermes model`, Hermes prefers Claude Code's own credential store over copying the token into `~/.hermes/.env`. This keeps refreshable credentials working properly.

**Copilot Alternative:**
```
copilot — Direct Copilot API (recommended)
```
Uses your GitHub Copilot subscription to access GPT-5.x, Claude, Gemini, and other models through the Copilot API.

---

## Auxiliary Vision Configuration

**Recommended setup for GPT-4o vision:**
```yaml
auxiliary:
  vision:
    provider: "openrouter"
    model: "openai/gpt-4o"
```

**Using Codex OAuth (ChatGPT Pro/Plus):**
```yaml
auxiliary:
  vision:
    provider: "codex"  # uses your ChatGPT OAuth token
    # model defaults to gpt-5.3-codex (supports vision)
```

---

## Token Overhead

Same 13.9K fixed overhead applies to OpenAI models:

| Component | Tokens |
|-----------|--------|
| Tool definitions | 8,759 |
| System prompt | 5,176 |
| **Fixed overhead** | **~13,935** |

---

## Community Feedback

### Positive
- Reliable tool calling
- Good for complex reasoning tasks
- Widely tested and supported

### Cost Considerations
- GPT-4 class models are expensive for high-volume usage
- Consider using budget models (GPT-4o-mini) for simpler tasks
- Token overhead adds significant cost multiplier

---

## Provider Agnostic Design

Hermes allows easy switching between providers:

```bash
hermes model  # Interactive provider selection
```

**Switch without code changes:**
- OpenAI → Anthropic → Local models
- No configuration file editing required
- API keys stored securely in `~/.hermes/.env`

---

## Recommendations

1. **Use GPT-4 class models** for complex architecture decisions
2. **Use GPT-4o-mini** for routine tasks to reduce costs
3. **Enable response caching** when available
4. **Monitor token usage** with `/usage` command
5. **Consider OpenRouter** for flexibility across multiple frontier models