Checks whether the Signalint MCP server is responsive. Read-only; returns the string "pong" with no side effects. Use this to verify the server is connected before running diagnostics. Invalid arguments return an error response; no authentication is required.

Runs and clusters Oxlint and TypeScript (and optionally Biome) lint and type diagnostics for one or more project paths. Read-only; no files are written or modified. Paths default to the project root (".") when omitted; paths must be relative and within the project directory — absolute paths or paths outside the root return an error response. Use this for a full project scan; use check_files instead for faster incremental checks after editing specific files. Each call re-runs all enabled engines with no caching.

Runs Oxlint and TypeScript (and optionally Biome) lint and type diagnostics on a specific list of files, using per-engine content-hash caching to skip unchanged files. Read-only; no files are written or modified. Use this for incremental checks after editing specific files; use check_project for a full project scan. The files parameter expects relative file paths (not glob patterns) within the project directory — absolute paths or paths outside the root return an error response. Caching is file-content-hash-based: a file is re-checked only when its content or the engine's config file (e.g., .oxlintrc, tsconfig.json) has changed since the last call, not based on git status. TypeScript is a whole-program engine: it re-runs whenever any TypeScript file in the request has changed content.

Returns the full issue list for either one cluster ID or one issue ID from the most recent check_project or check_files call. Read-only; no files are written or modified. Supply exactly one of clusterId or issueId — supplying both or neither returns an argument error. If the referenced cluster or issue no longer exists in the latest results (e.g., after re-running a check), returns a status: "stale" response instead of an error; call check_project or check_files again to refresh.

Returns all diagnostic issue signatures currently flagged as looping (repeatedly appearing and disappearing) in this server session. Read-only; no files are written or modified. Loop history is accumulated across all check_project and check_files calls in this process lifetime, and is restored from .signalint/session.jsonl on startup. Takes no parameters. Use this to identify which diagnostics an agent is oscillating on; use check_project or check_files to run fresh diagnostics.