ComfyUI MCP Server

Instructions

Implementation Reference

• comfy_mcp/mcp/server.py:242-277 (handler)

  The validate_workflow tool handler: parses DSL syntax using DSLParser, returns validation status, errors, node/section counts on success, or error details on failure.

  def validate_workflow(dsl: str) -> dict:
      """Validate DSL workflow syntax.
  
      Parses DSL and checks for syntax errors without executing the workflow.
      Returns validation status and any errors found.
  
      Args:
          dsl: Workflow content in DSL format
  
      Returns:
          Validation result with is_valid, errors, and warnings
  
      Examples:
          validate_workflow(dsl_content)
      """
      try:
          parser = DSLParser()
          workflow_ast = parser.parse(dsl)
  
          # If parsing succeeded, it's valid
          return {
              "is_valid": True,
              "errors": [],
              "warnings": [],
              "node_count": sum(len(section.nodes) for section in workflow_ast.sections),
              "section_count": len(workflow_ast.sections)
          }
  
      except Exception as e:
          return {
              "is_valid": False,
              "errors": [str(e)],
              "warnings": [],
              "message": "DSL syntax error"
          }