ruvnet/ruflo · error · Error

Missing required argument: ${arg.name}

Error message

Missing required argument: ${arg.name}

What it means

During PromptRegistry.get(), argument validation is enabled and one of the prompt's declared required arguments was absent from the caller's args object. The missing argument's name is included so the caller knows exactly what to supply before the prompt handler runs.

Source

Thrown at v3/@claude-flow/mcp/src/prompt-registry.ts:136

  }

  /**
   * Get a prompt with arguments
   */
  async get(
    name: string,
    args: Record<string, string> = {}
  ): Promise<PromptGetResult> {
    const prompt = this.prompts.get(name);
    if (!prompt) {
      throw new Error(`Prompt not found: ${name}`);
    }

    // Validate required arguments
    if (this.options.validateArguments && prompt.arguments) {
      for (const arg of prompt.arguments) {
        if (arg.required && !(arg.name in args)) {
          throw new Error(`Missing required argument: ${arg.name}`);
        }
      }
    }

    const messages = await prompt.handler(args);

    this.emit('prompt:get', { name, argCount: Object.keys(args).length });

    return {
      description: prompt.description,
      messages,
    };
  }

  /**
   * Get prompt by name
   */
  getPrompt(name: string): MCPPrompt | undefined {

View on GitHub (pinned to fa13ee4ad6)

Solutions

1. Supply the required argument in the getPrompt call.
2. Mark the argument optional in the prompt definition if it is not truly required.

When it happens

Trigger: Thrown at v3/@claude-flow/mcp/src/prompt-registry.ts:136 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of ruvnet/ruflo@fa13ee4ad6 (2026-08-18). Data as JSON: /api/errors/7512d41d22fabdb0. Report an issue: GitHub.