A Senior Stopped the Pairing Until the Session Lived in YAML

Description and use

During pairing, a YAML session contract was used and verified locally by a Python script to enforce constraints and stop conditions instead of relying on the LLM chat transcript.

Problem

Free LLM chat transcripts are unreliable for capturing pairing agreements; they can drift or be lost, making it hard to enforce constraints and review decisions.

Outcome

The pairing session now has a durable, schema‑validated contract that enforces invariants, budgets, and stop conditions locally, preventing drift and ensuring reproducibility.

Workflow

• 1. Create a "pairing/" directory with a session_contract.yaml and verify_session.py
• 2. Write the session contract (id, owner, max_minutes, max_model_calls, stop_on, invariants, budgets) before any model call
• 3. Run verify_session.py to load and validate the contract
• 4. Draft code with the free model, ensuring each reply is saved to disk
• 5. After each reply, run verify_session.py again to check invariants and budgets
• 6. If verification fails, abort the session or adjust the contract
• 7. Commit the contract and all artifacts to the repository
• 8. Use the verifier as the pairing partner that cannot be overridden during the hour

Evidence

Keep a versioned session contract in the repository. Verify it locally before every model call and after every saved reply.

Source