# Name lookup (llmcpp)

**Name lookup** resolves a name from the location of the generated body. This MCP request asks the compiler about the private field used in the repository's `Account` fixture:

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "lookup",
    "arguments": {
      "name": "Account::cents"
    }
  }
}
```

The JSON-RPC identifier matches the reply to this request. `lookup` returns declarations found and their usability from the active body's context.

Inside `Account::deposit`, `cents` is accessible; in the external `peek` function, access is restricted. Lookup can also check names such as `std::cout` rather than assuming their declarations are available.

Finding a declaration is not enough to validate every expression involving it. The agent uses [[llmcpp-candidate-compilation|candidate compilation]] to check its complete proposed body.