# Body submission (llmcpp)

**Body submission** delivers the implementation llmcpp should accept. The deposit fixture's final action corresponds to this MCP call:

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "submit",
    "arguments": {
      "body": "cents += amount;"
    }
  }
}
```

The active target is `Account::deposit(int amount)`, so the submitted text contains only its statements. The compiler checks that body before accepting it; a rejected submission uses one attempt.

After acceptance, the generation pass can cache the body and rewrite the source. An external agent also answers the original `llm/generate` request with completion status. Returning C++ only in that final response is insufficient: the tool-mediated submission identifies the checked implementation that belongs to the target.