ComfyUI MCP Server

Instructions

    Args:
        workflow_name: Workflow filename (e.g., 'my-workflow.json')

    Returns the workflow dict that can be modified and executed.
    

Implementation Reference

• src/comfy_mcp_server/tools/workflow.py:238-265 (handler)

  The core handler function for the 'load_workflow' tool. It uses Pydantic Field for input schema validation, loads the specified workflow JSON file from the configured directory, handles errors like missing directory or file, and returns the workflow dictionary.

  @mcp.tool()
  def load_workflow(
      workflow_name: str = Field(description="Workflow filename"),
      ctx: Context = None,
  ) -> dict:
      """Load a workflow file for inspection or modification.
  
      Args:
          workflow_name: Workflow filename (e.g., 'my-workflow.json')
  
      Returns the workflow dict that can be modified and executed.
      """
      if not settings.workflows_dir:
          return ErrorResponse.not_configured("COMFY_WORKFLOWS_DIR").model_dump()
  
      wf_path = Path(settings.workflows_dir) / workflow_name
      if not wf_path.exists():
          return ErrorResponse.not_found(
              f"Workflow '{workflow_name}'",
              suggestion="Use list_workflows() to see available workflows",
          ).model_dump()
  
      if ctx:
          ctx.info(f"Loading workflow: {workflow_name}")
  
      with open(wf_path) as f:
          return json.load(f)

• src/comfy_mcp_server/tools/__init__.py:27-27 (registration)

  Within register_all_tools, this line calls register_workflow_tools(mcp), which defines and registers the load_workflow tool using @mcp.tool() decorator.

  register_workflow_tools(mcp)

• src/comfy_mcp_server/__init__.py:92-92 (registration)

  The top-level call to register_all_tools(mcp) in the package init, which triggers the registration chain leading to load_workflow being registered.

  register_all_tools(mcp)

• src/comfy_mcp_server/tools/workflow.py:240-241 (schema)

  Pydantic Field defining the input schema for the workflow_name parameter of the load_workflow tool.

  workflow_name: str = Field(description="Workflow filename"),
  ctx: Context = None,