# Hermes

[Hermes Agent](https://hermes-agent.nousresearch.com) includes OpenCode providers for pay-as-you-go and Go. It picks the
right API for each paid or Go model. Free-tier chat models require OpenCode and return HTTP `403` from Hermes.

| Provider       | Plan          | Key variable           |
| -------------- | ------------- | ---------------------- |
| `opencode-zen` | Pay-as-you-go | `OPENCODE_ZEN_API_KEY` |
| `opencode-go`  | Go            | `OPENCODE_GO_API_KEY`  |

## Configure

Run the model setup and select **OpenCode Zen** for pay-as-you-go or **OpenCode Go** for Go.

```bash
hermes model
```

Paste a [personal API key](/console/harnesses#get-an-api-key), then choose a model. Hermes saves the
key to `~/.hermes/.env` and the selection to `~/.hermes/config.yaml`.

```yaml title="~/.hermes/config.yaml"
model:
  provider: opencode-go
  default: kimi-k3
```

<Callout>Go requires a session ID on every request. Hermes v0.21.6 and later send it automatically.</Callout>

## Models

Use model IDs from the [Console](/console/models#endpoints) or [Go](/console/go#endpoints) table without a prefix.
Switch models in a session with `/model`, or pick one for a single run.

```bash
hermes chat --provider opencode-zen --model claude-sonnet-5-5
```

## Console MCP

Add the [Console MCP](/console/harnesses#console-mcp) server with OAuth, then sign in from the browser.

```bash
hermes mcp add opencode-console --url https://opencode.ai/console/mcp --auth oauth
hermes mcp login opencode-console
```

Or add it to `~/.hermes/config.yaml` and run `/reload-mcp` in a session.

```yaml title="~/.hermes/config.yaml"
mcp_servers:
  opencode-console:
    url: https://opencode.ai/console/mcp
    auth: oauth
```