# MCP servers

MCP servers can be saved organization integrations or inline portable definitions attached to an eval.

## Command

| Command | Description |
| - | - |
| `lightsage mcp-servers list` | List MCP servers. |

## List MCP servers

```bash theme={null}
lightsage mcp-servers list --output-format json
```

The response includes transport metadata without exposing credentials, environment values, or OAuth secrets.

Use a saved MCP server ID in an eval or configuration:

```bash theme={null}
lightsage evals create \
  --name "Test MCP auth" \
  --prompt "List available tools." \
  --judge "Tools are listed." \
  --agent codex:gpt-5-4 \
  --mcp 550e8400-e29b-41d4-a716-446655440000

lightsage evals configurations create --eval-id eval_123 \
  --mcp-server-ids mcp_support_123 \
  --name "With supporting tools"
```

For an inline server, pass JSON or an `@file` containing one server definition:

```bash theme={null}
lightsage evals run \
  --prompt "List the available Lightsage tools." \
  --judge "The tools are listed." \
  --agent codex:gpt-5-4 \
  --mcp '{\n    "name": "lightsage",\n    "type": "http",\n    "url": "https://mcp.lightsage.com/mcp",\n    "headers": {\n      "X-Lightsage-Api-Key": "${LIGHTSAGE_API_KEY}"\n    }\n  }' \
  --env LIGHTSAGE_API_KEY="$LIGHTSAGE_API_KEY"
```

Inline definitions support `http`, `sse`, and `stdio`. Lightsage validates the definition and adapts it to the selected agent harness before queuing the run.