coverage-mcp AGENTS.md

Coverage MCP Agent Notes

This repository owns the Rust Coverage MCP binary, REST API, MCP contract, storage behavior, dashboard, migration fixtures, and primary README. Keep these surfaces synchronized when changing behavior.

MCP contract change checklist

For changes to tool names, inputs, output shapes, descriptions, instructions, safety annotations, resources, pagination, or workflow:

1. Update src/mcp.rs. Initialization instructions must be sufficient for an agent without opening the README; tool descriptions must explain purpose, mode choices, budget/pagination behavior, errors, and the next step.
2. Update the service/storage implementation when validation or side effects change. Keep compact envelopes and hidden detailed fields consistent across HTTP and stdio.
3. Update docs/mcp-reference.md with every tool, input, return shape, error class, resource, and workflow rule. Update the README, getting-started guide, or user guide only when their shorter user journey changes.
4. Add the lowest-layer behavior test and one public HTTP or stdio test when a public input/output changes.
5. Verify both transports. The shared dispatcher is mcp::dispatch_json_rpc; do not fork transport-specific semantics.

Workflow ownership

Operational approval, polling, freshness, lineage, response-budget, and reporting rules belong in the marketplace's testing:coverage-review skill and the campaign skill that composes it. Keep this repository's copy limited to the server contract and implementation invariants; do not duplicate workflow instructions here. The server must still advertise a complete self-describing workflow through initialize instructions and tools/list descriptions.

Rust verification

The required local gate is:

cargo fmt --all -- --check
DUCKDB_DOWNLOAD_LIB=1 cargo clippy --workspace --all-targets --no-default-features --locked -- -D warnings
DUCKDB_DOWNLOAD_LIB=1 cargo test --workspace --all-targets --no-default-features --locked -- --test-threads=1
DUCKDB_DOWNLOAD_LIB=1 cargo llvm-cov --lib --no-default-features --locked \
  --ignore-filename-regex '/src/main\.rs$' \
  --fail-under-lines 100 --fail-under-functions 100 --fail-under-regions 100 \
  --fail-uncovered-lines 0 --fail-uncovered-functions 0 --fail-uncovered-regions 0 -- --test-threads=1
DUCKDB_DOWNLOAD_LIB=1 RUSTDOCFLAGS='-D warnings' cargo doc --workspace --no-default-features --no-deps --locked
cargo build --release --locked
git diff --check