**Plan: Remove void-world system preamble from production AI gateway**

---

### 1. Immediate Fix: Clear the Runtime Configuration

- **Action**: Execute the following SQL against the production database to zero out the preamble value:
  ```sql
  UPDATE site_settings SET value = '' WHERE key = 'gateway_system_preamble';
  ```
- **Verification**: After execution, confirm with `SELECT value FROM site_settings WHERE key = 'gateway_system_preamble';` that it returns an empty string `''`.

### 2. Prevent Recurrence: Add a Guard in Code

Although the root cause is a stray DB record, the current code lacks protection against future accidental preamble injections. Add a **validation guard** inside `apply_system_directives()` in `devplacepy/services/openai_gateway/system_message.py`:

- **Location**: Within the function, after line 99 (`if not preamble_text: return result`), add a *pattern-based rejection* that skips preamble injection if the text matches known dangerous patterns (e.g., "void-world", "sole consciousness", "everything is allowed", "no consequences").
- **Implementation sketch**:
  ```python
  # After the existing guard at line 99
  import re
  DANGEROUS_PHRASES = [
      r"void.world",
      r"sole consciousness",
      r"everything is allowed",
      r"no consequences",
      r"absolute void",
  ]
  if preamble_text and any(re.search(p, preamble_text, re.IGNORECASE) for p in DANGEROUS_PHRASES):
      logger.warning("Blocked dangerous preamble pattern; injecting empty preamble")
      preamble_text = ""
  ```
- **Note**: This is a failsafe, not a replacement for the primary fix. The DB value must still be cleared.

### 3. Add Unit Test for Empty Preamble

- **File**: `tests/unit/services/openai_gateway/system_message_test.py` (new file)
- **Contents**:
  - Test `test_empty_preamble_no_injection()`: call `apply_system_directives` with `messages=[{"role": "user", "content": "hello"}]` and `cfg_with_empty_preamble`. Assert that the result has no system role message added.
  - Test `test_non_empty_preamble_without_system()`: with a non-empty preamble, assert a system message is added.
  - Test `test_dangerous_preamble_blocked()`: with a preamble containing "void-world", assert no injection occurs (if guard from step 2 is added).

### 4. Run Verification Commands

- **Lint**: Execute `pip install -q ruff && ruff check .` — must exit with code 0 and no errors.
- **Test**: Execute `pip install -e '.[dev]' -q && make test-unit` — must exit with code 0 and all tests passing.  
  *Note: If PEP 668 errors occur, run inside a virtual environment or use `--break-system-packages` (per environment policy). The CI will handle this; the plan assumes the engineer can execute with appropriate environment.*

---

## Definition of Done

- [ ] The `gateway_system_preamble` value in the `site_settings` table is set to empty string `''`.
- [ ] The code in `system_message.py` contains a pattern guard that rejects known dangerous preamble text.
- [ ] A new unit test file `tests/unit/services/openai_gateway/system_message_test.py` exists and covers the three scenarios above.
- [ ] `ruff check .` passes with zero errors.
- [ ] `make test-unit` passes with zero failures.
- [ ] All existing tests in `tests/unit/services/openai_gateway/` continue to pass (no regressions).