個人的GitHub Copilotの使い方メモ #VSCode – Qiita

import { spawn } from "node:child_process";
import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
import { z } from "zod";

type CodexCliExecutionResult = {
  stdout: string;
  stderr: string;
  exitCode: number | null;
};

type SandboxMode = "read-only" | "workspace-write";

const schema = z.object({
  cd: z
    .string()
    .describe("Codex CLI起動時に設定する作業ディレクトリを絶対パスで指定"),
  prompt: z.string().describe("Codex CLIに渡すプロンプト"),
});

const executeCodexCli = async (
  prompt: string,
  cd: string,
  sandbox: SandboxMode
): PromiseCodexCliExecutionResult> => {
  if (
    cd === "" ||
    !cd.startsWith(`${process.env.HOME}/`) ||
    cd.includes("..")
  ) {
    throw new Error(
      "Invalid 'cd' path. It must be an absolute path under the home directory."
    );
  }
  return new Promise((resolve, reject) => {
    const child = spawn(
      "codex",
      ["exec", prompt, "--cd", cd, "--sandbox", sandbox, "--profile", "mcp"],
      {
        stdio: ["pipe", "pipe", "pipe"],
        env: { PATH: process.env.PATH },
      }
    );
    let stdout = "";
    let stderr = "";

    child.stdin.end();

    child.stdout.on("data", (data: Buffer) => {
      stdout += data.toString();
    });
    child.stderr.on("data", (data: Buffer) => {
      stderr += data.toString();
    });

    child.on("close", (code: number | null) => {
      const exitCode = code ?? null;
      if (exitCode === 0) {
        const match =
          /\[[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}\] codex[\s\S]*/.exec(
            stdout
          );
        resolve({
          stdout: match ? match[0] : stdout,
          stderr,
          exitCode,
        });
      } else {
        reject(
          new Error(
            `Codex CLI エラー: ${
              stderr || stdout || "不明なエラー"
            } (exit code: ${exitCode})`
          )
        );
      }
    });

    child.on("error", reject);
  });
};

const createToolHandler =
  (sandbox: SandboxMode, promptTransformer?: (prompt: string) => string) =>
  async (args: { cd: string; prompt: string }) => {
    const { prompt, cd } = schema.parse(args);
    const transformedPrompt = promptTransformer
      ? promptTransformer(prompt)
      : prompt;
    const result = await executeCodexCli(transformedPrompt, cd, sandbox);
    return {
      content: [
        { type: "text" as const, text: result.stdout },
        ...(result.stderr.trim()
          ? [{ type: "text" as const, text: `stderr:\n${result.stderr}` }]
          : []),
      ],
    };
  };

const server = new McpServer({
  name: "my-codex-mcp",
  version: "0.1.0",
});

const main = async () => {
  server.registerTool(
    "plan",
    {
      description:
        "Codex CLIを利用して、指定されたタスクの詳細な実装計画を作成します。対象のコードを指定する場合は中身ではなく、ファイル名やディレクトリ名を指定する。",
      inputSchema: schema.shape,
    },
    createToolHandler("read-only")
  );

  server.registerTool(
    "act",
    {
      description:
        "Codex CLIを利用して、与えられた編集指示を実施します。対象のコードを指定する場合は中身ではなく、ファイル名やディレクトリ名を指定する。",
      inputSchema: schema.shape,
    },
    createToolHandler("workspace-write")
  );

  server.registerTool(
    "web_search",
    {
      description:
        "Codex CLIを利用して、指定されたキーワード（prompt）に基づいて、Web検索を行う",
      inputSchema: schema.shape,
    },
    createToolHandler("read-only", (prompt) => {
      return `以下の内容をWeb検索してください\n${prompt}`;
    })
  );

  const transport = new StdioServerTransport();
  await server.connect(transport);
};

main().catch((error) => {
  console.error("Fatal error in main():", error);
  process.exit(1);
});

[profiles.mcp]
model = "gpt-5-codex"
disable_response_storage = true
model_reasoning_effort = "medium"
hide_agent_reasoning = true