exec-command-recipes.md

Exec Command Recipes

These recipes intentionally use explicit exec_command commands. The MCP server does not infer project type, install dependencies automatically, or choose package-manager cache policy.

Foreground and background results

The server always exposes the same four process tools: exec_command, write_stdin, read_output, and kill_session. It does not dynamically add a tool after a command starts.

exec_command waits up to 10 seconds by default. If the command exits in that window, the result is complete and no polling call is needed. If it is still running, the result contains a session_id and an exact next_action, for example:

{
  "status": "running",
  "session_id": "sess_123",
  "next_action": {
    "tool": "write_stdin",
    "arguments": {
      "session_id": "sess_123",
      "chars": "",
      "yield_time_ms": 10000
    }
  }
}

Calling write_stdin with empty chars means “wait/poll”; non-empty chars interacts with the process. read_output is for paging retained stdout/stderr when a result explicitly says output was truncated (or when compact verbosity was requested). It is not an extra step for every command.

Use the external runtime HOME, TMPDIR, or cache_dir reported by server_info when you want dependency caches without adding files to the Git worktree. These shell examples assume trusted mode because they use environment expansion:

MAVEN_USER_HOME="$HOME/.cache/m2" mvn test
GRADLE_USER_HOME="$HOME/.cache/gradle" ./gradlew test
npm_config_cache="$HOME/.cache/npm" npm ci && npm test
PIP_CACHE_DIR="$HOME/.cache/pip" python -m pip install -r requirements.txt && python -m pytest
GOCACHE="$HOME/.cache/go-build" GOMODCACHE="$HOME/.cache/go-mod" go test ./...
CARGO_HOME="$HOME/.cache/cargo" cargo test
cmake -S . -B "$TMPDIR/cmake-build" && cmake --build "$TMPDIR/cmake-build" && ctest --test-dir "$TMPDIR/cmake-build"

Primitive toolchain checks:

java -version
javac -version
mvn -version
gcc --version
g++ --version
make --version
cmake --version
node --version
npm --version
python --version
pip --version
go version
cargo --version
rustc --version

If dependencies need network access, start with:

coding-tools-mcp --permission-mode trusted --workspace /path/to/repo