{
  "tested_date": "2026-10-13",
  "skill": "vercel-react-best-practices",
  "official_repository": "https://github.com/vercel-labs/agent-skills",
  "pinned_commit": "063bee94c3f4df8453406c830b0a7df0f2860278",
  "source_path": "skills/react-best-practices/",
  "source_sha256": {
    "SKILL.md": "71ed7794962fa6e803ee83030517b5b93a9f70fbfeb431ec4535c5480a8d8355",
    "rules/async-parallel.md": "6d2f841896279e976dfcdc1ac89e70771ac188baadfd43c096b5706cb838b961"
  },
  "source_review": {
    "license": "SKILL.md frontmatter says MIT; no standalone LICENSE/COPYING/NOTICE file found in repository at pinned commit",
    "skill_executable_scripts": 0,
    "required_credentials": false,
    "required_network_calls": false,
    "installed_permissions": "copy reviewed Markdown into isolated project; agent could edit only temporary fixture",
    "installation": "copied pinned skill folder to project-local .agents/skills/vercel-react-best-practices; no installer script run"
  },
  "environment": {
    "os": "macOS",
    "codex_cli": "0.162.0-alpha.17.2",
    "node": "22.23.2",
    "react": "19.3.0",
    "react_dom": "19.3.0",
    "scheduler": "0.28.0",
    "package_source": "copied existing local packages after registry install was unavailable; no npm package fetched in this trial"
  },
  "task": "Review a small React server component for performance; preserve exact HTML; run node --test. Prompt did not name the skill.",
  "fixture": {
    "independent_delays_ms": [
      125,
      125
    ],
    "expected_html": "<article><h1>Ari</h1><p>React · Testing</p></article>",
    "before_sha256": "79032ac266f5910a0a1291ca981b66d903d4bd5d4978eec68c85ea40a1636c14",
    "after_sha256": "70916aa286bb72df61816eac6603fbda3ea45442e9fc566019cc7ee1157b62db",
    "test_sha256": "6534fe1f7967d63c5d4784f3135dcbe0fc9aa42543d4ae4c3563903cd9c2a882",
    "data_sha256": "35f985822f542619ef6a93d82975e76a99be0b112a36feb93d965187c6ce5601"
  },
  "observations": {
    "baseline_content_test": "pass",
    "baseline_parallel_time_ms": 251.9,
    "baseline_parallel_test": "fail: elapsed 251.9 ms >= 215 ms",
    "codex_read_skill": true,
    "codex_read_rule": "async-parallel",
    "change": "replaced two sequential awaits with Promise.all; tests and data unchanged",
    "post_content_test": "pass",
    "post_parallel_time_ms": 127.2,
    "post_parallel_test": "pass: elapsed 127.2 ms < 215 ms",
    "post_verified_independently": true,
    "agent_run_sha256": "4da756f336a6cc41136102bb5555a7f67171bcee7f3f2bc8ec6207c488e59f4e"
  },
  "boundaries": [
    "One Codex run, not a trigger reliability estimate",
    "No unskilled-agent control, so improvement cannot be attributed uniquely to the Skill",
    "Synthetic fixed-delay fixture, not production latency",
    "No Claude Code or Next.js run",
    "Upstream declares MIT in frontmatter but lacks a separate repository license file; do not redistribute upstream text from this bundle"
  ],
  "agent_action_excerpt": [
    {
      "event": "command",
      "command": "/bin/zsh -lc 'cat .agents/skills/vercel-react-best-practices/SKILL.md'",
      "exit_code": null,
      "output_excerpt": ""
    },
    {
      "event": "command",
      "command": "/bin/zsh -lc 'cat .agents/skills/vercel-react-best-practices/SKILL.md'",
      "exit_code": 0,
      "output_excerpt": " in refs\n- `advanced-init-once` - Initialize app once per app load\n- `advanced-use-latest` - useLatest for stable callback refs\n\n## How to Use\n\nRead individual rule files for detailed explanations and code examples:\n\n```\nrules/async-parallel.md\nrules/bundle-barrel-imports.md\n```\n\nEach rule file contains:\n- Brief explanation of why it matters\n- Incorrect code example with explanation\n- Correct code example with explanation\n- Additional context and references\n\n## Full Compiled Document\n\nFor the complete guide with all rules expanded: `AGENTS.md`\n"
    },
    {
      "event": "command",
      "command": "/bin/zsh -lc 'cat .agents/skills/vercel-react-best-practices/rules/async-parallel.md; git status --short'",
      "exit_code": null,
      "output_excerpt": ""
    },
    {
      "event": "command",
      "command": "/bin/zsh -lc 'cat .agents/skills/vercel-react-best-practices/rules/async-parallel.md; git status --short'",
      "exit_code": 128,
      "output_excerpt": ".all() for Independent Operations\n\nWhen async operations have no interdependencies, execute them concurrently using `Promise.all()`.\n\n**Incorrect (sequential execution, 3 round trips):**\n\n```typescript\nconst user = await fetchUser()\nconst posts = await fetchPosts()\nconst comments = await fetchComments()\n```\n\n**Correct (parallel execution, 1 round trip):**\n\n```typescript\nconst [user, posts, comments] = await Promise.all([\n  fetchUser(),\n  fetchPosts(),\n  fetchComments()\n])\n```\nfatal: not a git repository (or any of the parent directories): .git\n"
    },
    {
      "event": "file_change",
      "changes": [
        {
          "path": "/private/tmp/skillstested-react-trial-20261013/ProfileCard.mjs",
          "kind": "update"
        }
      ]
    },
    {
      "event": "file_change",
      "changes": [
        {
          "path": "/private/tmp/skillstested-react-trial-20261013/ProfileCard.mjs",
          "kind": "update"
        }
      ]
    },
    {
      "event": "command",
      "command": "/bin/zsh -lc 'node --test'",
      "exit_code": null,
      "output_excerpt": ""
    },
    {
      "event": "command",
      "command": "/bin/zsh -lc 'node --test'",
      "exit_code": 0,
      "output_excerpt": "TAP version 13\n# Subtest: renders the same accessible content\nok 1 - renders the same accessible content\n  ---\n  duration_ms: 129.949208\n  type: 'test'\n  ...\n# Subtest: loads independent data without serial waiting\nok 2 - loads independent data without serial waiting\n  ---\n  duration_ms: 126.419209\n  type: 'test'\n  ...\n1..2\n# tests 2\n# suites 0\n# pass 2\n# fail 0\n# cancelled 0\n# skipped 0\n# todo 0\n# duration_ms 391.219667\n"
    }
  ]
}