MOCK_PARITY_HARNESS.md

Mock LLM parity harness

This milestone adds a deterministic Anthropic-compatible mock service plus a reproducible CLI harness for the Rust claw binary.

Artifacts

• crates/mock-anthropic-service/ — mock /v1/messages service
• crates/rusty-claude-cli/tests/mock_parity_harness.rs — end-to-end clean-environment harness
• scripts/run_mock_parity_harness.sh — convenience wrapper

Scenarios

The harness runs these scripted scenarios against a fresh workspace and isolated environment variables:

1. streaming_text
2. read_file_roundtrip
3. grep_chunk_assembly
4. write_file_allowed
5. write_file_denied
6. multi_tool_turn_roundtrip
7. bash_stdout_roundtrip
8. bash_permission_prompt_approved
9. bash_permission_prompt_denied
10. plugin_tool_roundtrip

Run

cd rust/
./scripts/run_mock_parity_harness.sh

Behavioral checklist / parity diff:

cd rust/
python3 scripts/run_mock_parity_diff.py

Scenario-to-PARITY mappings live in mock_parity_scenarios.json.

Manual mock server

cd rust/
cargo run -p mock-anthropic-service -- --bind 127.0.0.1:0

The server prints MOCK_ANTHROPIC_BASE_URL=...; point ANTHROPIC_BASE_URL at that URL and use any non-empty ANTHROPIC_API_KEY.