MCP-TY

Instructions

Implementation Reference

• src/mcp_ty/server.py:626-667 (handler)

  This function is the MCP tool handler 'get_code_actions', which gets diagnostics for a file path and calls the underlying LSP client to retrieve code actions.

  @mcp.tool()
  async def get_code_actions(file_path: str, line: int, column: int) -> str:
      """Get available quick fixes and refactorings at position (1-based)."""
      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(0.3)
  
          diagnostics = client.get_diagnostics(path)
          relevant_diags = [
              d for d in diagnostics
              if d.range.start.line <= line - 1 <= d.range.end.line
          ]
  
          actions = await client.get_code_actions(
              path, line - 1, column - 1, line - 1, column, relevant_diags
          )
  
          if not actions:
              return _not_found(f"No actions at {path.name}:{line}:{column}")
  
          action_list = []
          for i, action in enumerate(actions, 1):
              action_list.append({
                  "index": i,
                  "title": action.title,
                  "kind": action.kind or None,
                  "has_edit": action.edit is not None
              })
  
          return _ok({"count": len(actions), "actions": action_list})
  
      except Exception as e:
          return _error(str(e))

• src/mcp_ty/lsp_client.py:713-745 (helper)

  This is the underlying LSP client method that performs the actual communication with the language server to get code actions.

  async def get_code_actions(
      self, file_path: str | Path, start_line: int, start_char: int,
      end_line: int, end_char: int, diagnostics: list[Diagnostic] | None = None
  ) -> list[CodeAction]:
      """Get available code actions (quick fixes, refactorings) for a range."""
      file_path = Path(file_path).resolve()
      uri = file_path.as_uri()
  
      context: dict[str, Any] = {"diagnostics": []}
      if diagnostics:
          for diag in diagnostics:
              context["diagnostics"].append({
                  "range": diag.range.to_dict(),
                  "message": diag.message,
                  "severity": diag.severity,
                  "source": diag.source,
                  "code": diag.code
              })
  
      result = await self._send_request("textDocument/codeAction", {
          "textDocument": {"uri": uri},
          "range": {
              "start": {"line": start_line, "character": start_char},
              "end": {"line": end_line, "character": end_char}
          },
          "context": context
      })
  
      if not result:
          return []
  
      actions = []
      for item in result: