MCP Server RubyGems

Instructions

Implementation Reference

• src/tools/get_gem_owners.ts:24-38 (handler)

  Core handler function that fetches the owners of a RubyGem from the RubyGems API and validates the response.

  async function getGemOwners(gemName: string): Promise<GemOwner[]> {
    const response = await fetch(
      `https://rubygems.org/api/v1/gems/${gemName}/owners.json`
    );
  
    if (!response.ok) {
      if (response.status === 404) {
        throw new Error(`RubyGem '${gemName}' not found`);
      }
      throw new Error(`Failed to fetch gem owners: ${response.statusText}`);
    }
  
    const data = await response.json();
    return z.array(GemOwnerSchema).parse(data);
  }

• src/tools/get_gem_owners.ts:16-21 (schema)

  Input schema defining the gem_name parameter for the get_gem_owners tool.

  const GetGemOwnersInputSchema = z.object({
    gem_name: z
      .string()
      .min(1)
      .describe('Name of the RubyGem to fetch owners for'),
  });

• src/tools/get_gem_owners.ts:7-11 (schema)

  Schema for individual gem owner objects used in the response validation.

  const GemOwnerSchema = z.object({
    id: z.number(),
    handle: z.string(),
    email: z.string().optional(),
  });

• src/tools/get_gem_owners.ts:41-65 (registration)

  MCP tool registration including name, description, input schema conversion, and wrapper handler that parses input, calls the core handler, formats response, and handles errors.

  export const getGemOwnersTool: McpTool = {
    name: 'get_gem_owners',
    description: 'Get the owners of a specific RubyGem',
    inputSchema: {
      type: 'object',
      properties: zodToJsonSchema(GetGemOwnersInputSchema),
    },
    handler: async (args: Record<string, unknown> | undefined) => {
      const { gem_name } = GetGemOwnersInputSchema.parse(args || {});
  
      try {
        const owners = await getGemOwners(gem_name);
        return {
          content: [
            {
              type: 'text',
              text: JSON.stringify(owners, null, 2),
            },
          ],
        };
      } catch (error: unknown) {
        return createErrorResponse(error, 'Failed to fetch gem owners');
      }
    },
  };

• src/index.ts:20-27 (registration)

  Registration of all tools including getGemOwnersTool in the server's tools array.

  const tools: readonly McpTool[] = [
    getRubyGemInfoTool,
    searchRubyGemsTool,
    getGemVersionsTool,
    getGemReverseDependenciesTool,
    getOwnerGemsTool,
    getGemOwnersTool,
  ] as const;