nerfdetector

nerfdetector monitors real-time model performance. Is your model nerfed?

When Claude, GPT, Gemini, or Grok is having a bad day, you shouldn't have to wonder if it's just you. nerfdetector watches your AI coding sessions and lets you report how it's going — one keypress at the end of every session.

Install

npm i -g nerfdetector
nerfdetector

nerfdetector detects your AI coding tools (Claude Code, Codex CLI, Gemini CLI) and installs lightweight hooks. The install process explains exactly what data it will and will not collect.

How it works

1. You use Claude Code / Codex / Gemini normally
2. At session start, you see how your model is doing globally:

nerfdetector · Claude Opus 4.6: 🔴 12% sentiment · 40 reports

3. After meaningful work, one line appears:

nerfdetector · claude-opus-4-6 (100%) · 23 actions · 4 failed · 3 retries
how was your session? [f] fine  [m] mid  [n] nerfed  [s] skip

4. Press one key. Done.

• f — sends your vote as "fine"
• m — sends your vote as "mid" (worked but mediocre)
• n — sends your vote as "nerfed"
• s or wait 5 seconds — skips vote, sends anonymous telemetry

Your vote is weighted by which models you actually used — if you used Opus and Sonnet in the same session, the vote counts proportionally against each.

Commands

nerfdetector              detect tools + install hooks (same as init)
nerfdetector init         detect tools + install hooks
nerfdetector help         show help
nerfdetector status       your session + global model status
nerfdetector history      your personal trends (--days 7 or --days 30)
nerfdetector report       vote on your session (--fine, --mid, or --nerfed)
nerfdetector export       dump local events as JSON (privacy audit)
nerfdetector uninstall    remove all hooks

What it tracks

nerfdetector tracks quality signals from your sessions and builds a personal baseline over time:

• Tool success rate — how many actions succeeded vs failed
• Retry loops — consecutive same-tool calls (model stuck in a loop)
• Latency — time between actions (is the model getting slower?)

To check if a session deviates significantly from your norm, you can run nerfdetector history to view a summary of your usage.

$ nerfdetector history

  claude-opus-4-6 · 154 actions

  success rate       92% →    78%  ▼ 14pts
  retry rate          6% →    19%  ▲ 3.2x
  latency           3.2s →   7.8s  ▲ 2.4x slower
  nerfed rate        12% →    45%  ▲ 3.8x more

  date    success                 actions retries  vote
  ────────────────────────────────────────────────────────────
  Apr 08  ███████████████░  94%        18       3%   🟢 fine
  Apr 09  ████████████░░░░  83%        23      13%   🟡 mid
▼ Apr 10  ██████████░░░░░░  67%        31      26%   🔴 nerfed
▼ Apr 11  █████████░░░░░░░  60%        15      33%   🔴 nerfed
  Apr 12  ██████████████░░  91%        22       5%   🟢 fine
▲ Apr 14  ███████████████░  92%        25       4%   🟢 fine

  insights · 12 voted sessions
  • 4.9× more retries when you vote nerfed vs fine
  • 73% of your evening sessions end with nerfed
  • your baseline shifted -18% since Apr 10

Baselines and history never leave your machine.

What gets collected

Sent when you vote:

• Which models you used
• How many actions succeeded or failed
• How often the model retried

Never sent:

• Prompts or responses
• File paths or code
• Error messages or tool output content
• Personally identifying information
• Your personal baselines

All events are stored locally in ~/.nerfdetector/events.db. Run nerfdetector export anytime to verify.

Supported tools

| Tool | Status | |---|---| | Claude Code | Full support | | Codex CLI | Full support | | Gemini CLI | Full support |

Uninstall

nerfdetector uninstall
npm uninstall -g nerfdetector
rm -rf ~/.nerfdetector   # remove local data

License

MIT