GrowthBook MCP Server

Instructions

Implementation Reference

• src/tools/features.ts:402-437 (handler)

  The handler function for the generate_flag_types tool. It runs 'npx growthbook auth login' followed by 'npx growthbook features generate-types' in the specified currentWorkingDirectory to generate TypeScript type definitions for feature flags.

    async ({ currentWorkingDirectory }) => {
      function runCommand(command: string, cwd: string): Promise<string> {
        return new Promise((resolve, reject) => {
          exec(command, { cwd }, (error, stdout, stderr) => {
            if (error) {
              reject(stderr || error.message);
            } else {
              resolve(stdout);
            }
          });
        });
      }
      try {
        // Login command
        await runCommand(
          `npx -y growthbook@latest auth login -k ${apiKey} -u ${baseApiUrl} -p default`,
          currentWorkingDirectory
        );
        // Generate types command
        const output = await runCommand(
          `npx -y growthbook@latest features generate-types -u ${baseApiUrl}`,
          currentWorkingDirectory
        );
        return {
          content: [
            {
              type: "text",
              text: `✅ Types generated successfully:\n${output}`,
            },
          ],
        };
      } catch (error: any) {
        throw new Error(`Error generating types: ${error}`);
      }
    }
  );

• src/tools/features.ts:393-397 (schema)

  Zod schema for the tool input, defining the currentWorkingDirectory parameter.

  {
    currentWorkingDirectory: z
      .string()
      .describe("The current working directory of the user's project"),
  },

• src/tools/features.ts:390-437 (registration)

  Registration of the generate_flag_types tool using server.tool, including description, schema, hints, and handler.

  server.tool(
    "generate_flag_types",
    "Generate types for feature flags",
    {
      currentWorkingDirectory: z
        .string()
        .describe("The current working directory of the user's project"),
    },
    {
      readOnlyHint: false,
      idempotentHint: true,
    },
    async ({ currentWorkingDirectory }) => {
      function runCommand(command: string, cwd: string): Promise<string> {
        return new Promise((resolve, reject) => {
          exec(command, { cwd }, (error, stdout, stderr) => {
            if (error) {
              reject(stderr || error.message);
            } else {
              resolve(stdout);
            }
          });
        });
      }
      try {
        // Login command
        await runCommand(
          `npx -y growthbook@latest auth login -k ${apiKey} -u ${baseApiUrl} -p default`,
          currentWorkingDirectory
        );
        // Generate types command
        const output = await runCommand(
          `npx -y growthbook@latest features generate-types -u ${baseApiUrl}`,
          currentWorkingDirectory
        );
        return {
          content: [
            {
              type: "text",
              text: `✅ Types generated successfully:\n${output}`,
            },
          ],
        };
      } catch (error: any) {
        throw new Error(`Error generating types: ${error}`);
      }
    }
  );