AIエージェントを信頼できる相棒にする — ハーネスエンジニアリングの4本柱と実運用設計

# AI エージェントのポリシー（YAML定義）
constraints:
  forbidden_operations:
    - delete_file
    - force_push
    - modify_permissions
    - update_dependencies_without_approval
  allowed_operations:
    - add_comment
    - suggest_changes
    - run_linter
    - propose_refactoring

// AI への文脈提供の例
const codeReviewContext = {
  // ファイルの基本情報
  filename: "src/auth/login.ts",
  language: "typescript",
  
  // 変更内容
  changes: {
    added_lines: 45,
    removed_lines: 12,
    diff: "...", // unified diff
  },
  
  // プロジェクトの文脈
  project_standards: {
    coding_style: "Airbnb",
    test_coverage_minimum: 80,
    security_requirements: "OWASP Top 10 compliant",
  },
  
  // テスト結果
  test_results: {
    unit_tests: "PASS",
    type_check: "PASS",
    security_scan: "FAIL (1 medium, 0 critical)",
  },
  
  // コミット履歴（このファイルの最近の変更）
  recent_commits: [
    "fix: SQL injection vulnerability",
    "feat: add MFA support",
    "refactor: extract auth logic",
  ],
};

#!/bin/bash
# AI が修正を提案した後、自動検証を実行
 
echo "=== Verification Step ==="
 
# 1. Linter チェック
echo "Running ESLint..."
npx eslint src/auth/login.ts --fix
if [ $? -ne 0 ]; then
  echo "FAIL: Linter errors detected"
  exit 1
fi
 
# 2. 型チェック
echo "Running TypeScript compiler..."
npx tsc --noEmit
if [ $? -ne 0 ]; then
  echo "FAIL: Type errors detected"
  exit 1
fi
 
# 3. ユニットテスト実行
echo "Running unit tests..."
npm test -- src/auth/login.test.ts
if [ $? -ne 0 ]; then
  echo "FAIL: Tests failed"
  exit 1
fi
 
# 4. セキュリティチェック
echo "Running security scan..."
npx snyk test --severity-threshold=high
if [ $? -ne 0 ]; then
  echo "FAIL: Security vulnerabilities found"
  exit 1
fi
 
echo "✓ All verifications passed"

// 修正プロセスの擬似コード
async function autoReviewFlow(prContent: string): Promise<void> {
  // Step 1: Constrain - どんな操作が許可されているか確認
  const allowedActions = validateConstraints(prContent);
  
  // Step 2: Inform - AI に必要な文脈を提供
  const context = gatherContext(prContent);
  
  // Step 3: Verify - AI の提案を検証
  const validation = await runVerificationSuite(context);
  
  if (!validation.passed) {
    // Step 4: Correct - エラーをフィードバックして修正を試みる
    const feedbackMessages = formatVerificationErrors(validation);
    const fixAttempt = await ai.generateFix({
      originalCode: prContent,
      errors: feedbackMessages,
      constraints: allowedActions,
    });
    
    // 修正版を再検証
    const retryValidation = await runVerificationSuite(fixAttempt);
    if (retryValidation.passed) {
      console.log("✓ Auto-fix successful");
      return fixAttempt;
    } else {
      console.log("✗ Auto-fix failed, requiring human review");
      return null;
    }
  }
}

// GitHub Actions ワークフロー
import { Octokit } from "@octokit/rest";
 
const octokit = new Octokit({ auth: process.env.GITHUB_TOKEN });
 
async function triggerReview(owner: string, repo: string, pr: number) {
  const { data: prData } = await octokit.pulls.get({ owner, repo, pull_number: pr });
  
  console.log(`Reviewing PR #${pr}: ${prData.title}`);
  // AI レビュー処理へ
}

async function gatherChangeContext(owner: string, repo: string, pr: number) {
  // PR の変更ファイル一覧を取得
  const { data: files } = await octokit.pulls.listFiles({ owner, repo, pull_number: pr });
  
  // 各ファイルの diff を取得
  const changes = await Promise.all(
    files.map(async (file) => ({
      filename: file.filename,
      diff: file.patch,
      additions: file.additions,
      deletions: file.deletions,
    }))
  );
  
  return changes;
}

async function performAIReview(changes: any[], context: any) {
  const reviewPrompt = `
You are a code reviewer. Review the following changes:
 
${changes.map(c => `File: ${c.filename}\n${c.diff}`).join("\n---\n")}
 
Constraints:
- Only suggest improvements, do NOT modify files directly
- Flag security issues (SQL injection, XSS, etc.)
- Check for performance issues
- Verify test coverage (minimum 80%)
- Suggest refactoring only if it significantly improves readability
 
Respond with JSON format:
{
  "severity": "CRITICAL|HIGH|MEDIUM|LOW",
  "type": "security|performance|style|testing",
  "line": <line_number>,
  "suggestion": "<human-readable suggestion>"
}
  `;
  
  const review = await ai.analyze(reviewPrompt);
  return review;
}

#!/bin/bash
# verify.sh - 検証を自動実行
 
set -e
 
echo "Running verification suite..."
 
# Linting
npm run lint 2>&1 | tee lint-output.txt || LINT_STATUS=$?
 
# Type checking
npm run typecheck 2>&1 | tee typecheck-output.txt || TYPE_STATUS=$?
 
# Unit tests
npm test -- --coverage 2>&1 | tee test-output.txt || TEST_STATUS=$?
 
# Security scanning
npx snyk test 2>&1 | tee security-output.txt || SECURITY_STATUS=$?
 
# Summary
if [ -z "$LINT_STATUS" ] && [ -z "$TYPE_STATUS" ] && [ -z "$TEST_STATUS" ]; then
  echo "✓ All checks passed"
  exit 0
else
  echo "✗ Some checks failed"
  exit 1
fi

async function autoFixAndComment(owner: string, repo: string, pr: number, issues: any[]) {
  // CRITICAL/HIGH 問題のみ修正を試みる
  const critical = issues.filter(i => i.severity === "CRITICAL" || i.severity === "HIGH");
  
  if (critical.length > 0) {
    const fixPrompt = `
These critical issues were found:
${critical.map(i => `- ${i.suggestion}`).join("\n")}
 
Generate a fix that:
1. Addresses the issues above
2. Does NOT break existing tests
3. Maintains code style consistency
    `;
    
    const fix = await ai.generateFix(fixPrompt);
    
    // PR にコメント
    await octokit.issues.createComment({
      owner, repo, issue_number: pr,
      body: `## 🤖 Auto-Review Results\n\n${formatReviewResults(issues)}`,
    });
  }
}

# 重要度フィルタリング
severity_levels:
  CRITICAL:  # セキュリティ脆弱性、テスト失敗
    action: block_merge
  HIGH:      # パフォーマンス問題、コード規約大幅違反
    action: comment_and_request_fix
  MEDIUM:    # スタイル改善、軽度の構造改変
    action: comment_only
  LOW:       # 単語のスペル、コメント修正
    action: ignore

// 修正履歴を追跡し、同じファイルの同じ行で 2 回以上の修正を防ぐ
const modificationHistory: Map<string, Set<number>> = new Map();
 
function preventOscillation(filename: string, lineNumber: number): boolean {
  if (!modificationHistory.has(filename)) {
    modificationHistory.set(filename, new Set());
  }
  
  const lines = modificationHistory.get(filename)!;
  if (lines.has(lineNumber)) {
    console.log("⚠️ Oscillation detected, skipping");
    return false; // この行は修正しない
  }
  
  lines.add(lineNumber);
  return true;
}

# 実行前に権限チェック
ALLOWED_PATHS=(
  "src/**"
  "tests/**"
  "docs/**"
)
 
FORBIDDEN_OPERATIONS=(
  "rm -rf"
  "npm update"
  "git push --force"
  "git revert"
)
 
for forbidden in "${FORBIDDEN_OPERATIONS[@]}"; do
  if grep -q "$forbidden" proposed_changes.txt; then
    echo "❌ Forbidden operation detected: $forbidden"
    exit 1
  fi
done