# Todo 53.4: Managed EventPrompt Test Identity

## Problem

The Todo 53.3 behavior test gives the managed EventPrompt and generated-signature custom impostor identical content. Its expected output therefore proves only that one string remains, not that the collector retained the managed item.

## Scope

- Change only `tests/test_websocket_api.py`.
- Use two different strings that both satisfy the conservative generated EventPrompt signature.
- Assign one to the custom impostor and the other to the managed `event_agent_system` item.
- Assert `dual_agent` retains the managed content and rejects the impostor.
- Assert `chat_agent_tools` rejects both generated contents while preserving ordinary custom prompts.
- Do not change production code.

## Verification

- Run the focused EventPrompt test and the full WebSocket test file.
- Run Node syntax and diff checks.
- Repeat specification and code-quality review for Todo 53.3/53.4 together.