pack

Instructions

Implementation Reference

• src/index.ts:257-278 (handler)

  The `pack` tool handler function. It takes `path` (absolute path to package directory) and optional `dryRun` (boolean to list files without creating tarball). It runs `npm pack --json` via the `run()` helper and returns the JSON output.

  server.tool(
    "pack",
    "Create a tarball from a package (preview what would be published)",
    {
      path: z.string().describe("Absolute path to the package directory"),
      dryRun: z.boolean().optional().describe("List files without creating tarball"),
    },
    async ({ path, dryRun }) => {
      const args = ["pack"];
      if (dryRun) args.push("--dry-run");
      args.push("--json");
      try {
        const { stdout } = await run(args, path);
        return { content: [{ type: "text", text: stdout }] };
      } catch (e: any) {
        return {
          content: [{ type: "text", text: `Error: ${e.stderr || e.message}` }],
          isError: true,
        };
      }
    },
  );

• src/index.ts:256-278 (registration)

  Registration of the `pack` tool via `server.tool('pack', ...)`. Defines the tool name as 'pack' with description 'Create a tarball from a package (preview what would be published)'.

  // ── npm pack ──
  server.tool(
    "pack",
    "Create a tarball from a package (preview what would be published)",
    {
      path: z.string().describe("Absolute path to the package directory"),
      dryRun: z.boolean().optional().describe("List files without creating tarball"),
    },
    async ({ path, dryRun }) => {
      const args = ["pack"];
      if (dryRun) args.push("--dry-run");
      args.push("--json");
      try {
        const { stdout } = await run(args, path);
        return { content: [{ type: "text", text: stdout }] };
      } catch (e: any) {
        return {
          content: [{ type: "text", text: `Error: ${e.stderr || e.message}` }],
          isError: true,
        };
      }
    },
  );

• src/index.ts:260-263 (schema)

  Input schema for the `pack` tool using Zod: `path` (required string), `dryRun` (optional boolean).

  {
    path: z.string().describe("Absolute path to the package directory"),
    dryRun: z.boolean().optional().describe("List files without creating tarball"),
  },

• src/index.ts:26-38 (helper)

  The `run()` helper function that executes npm commands. Wraps `execFile` with the configured npm binary and optional .npmrc token arguments.

  async function run(
    args: string[],
    cwd?: string,
  ): Promise<{ stdout: string; stderr: string }> {
    const fullArgs = [...args, ...npmrcArgs];
    const opts: { cwd?: string; timeout: number; env: NodeJS.ProcessEnv; maxBuffer: number } = {
      timeout: 120_000,
      maxBuffer: 10 * 1024 * 1024, // 10MB buffer for large outputs
      env: { ...process.env, NO_COLOR: "1" },
    };
    if (cwd) opts.cwd = cwd;
    return exec(NPM, fullArgs, opts);
  }

• src/index.ts:1252-1255 (registration)

  Sandbox registration of the `pack` tool (noop handler for testing).

  sandbox.tool("pack", "Create a tarball from a package", {
    path: z.string().describe("Absolute path to the package directory"),
    dryRun: z.boolean().optional().describe("List files without creating tarball"),
  }, noop);