MCP-TY

Instructions

Implementation Reference

• src/mcp_ty/server.py:435-461 (handler)

  MCP tool handler for 'get_diagnostics' which calls the underlying LSP client.

  @mcp.tool()
  async def get_diagnostics(file_path: str) -> str:
      """Get type errors and warnings for a file."""
      client = _get_client()
  
      path = Path(file_path).resolve()
      if not path.exists():
          return _error(f"File not found: {file_path}")
  
      try:
          await client.open_document(path)
  
          import asyncio
          await asyncio.sleep(0.5)
  
          diagnostics = client.get_diagnostics(path)
  
          if not diagnostics:
              return _ok({"file": path.name, "count": 0, "diagnostics": []})
  
          diag_list = []
          for diag in diagnostics:
              severity = SEVERITY_MAP.get(diag.severity or 1, "error")
              diag_list.append({
                  "line": diag.range.start.line + 1,
                  "column": diag.range.start.character + 1,
                  "severity": severity,

• src/mcp_ty/lsp_client.py:624-628 (helper)

  The underlying LSP client method that retrieves cached diagnostics for a given file path.

  def get_diagnostics(self, file_path: str | Path) -> list[Diagnostic]:
      """Get cached diagnostics for a file."""
      file_path = Path(file_path).resolve()
      uri = file_path.as_uri()
      return self._diagnostics.get(uri, [])