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@IyadhKhalfallah/clauditor

Claude Code hooks for session rotation and handoff context

clauditor adds hooks to Claude Code that measure session waste, block oversized sessions, and save context before you start a fresh one. It also reads saved session files back into new sessions, shows reports, and can track recurring errors and file activity over time.

428 stars42 forksTypeScriptUpdated 5mo ago
Who it's for

Builders who run Claude Code and want reusable session rotation and resume logic.

What it delivers

You can stop long Claude Code sessions before they burn through quota and pick up again without re-explaining the work.

What it does

Blocks wasteful sessions

`UserPromptSubmit` and `PostToolUse` compare current token use against a baseline and stop sessions that have grown too expensive.

Saves handoff context

`PreCompact` and `PostCompact` capture session state, including Claude's summary and structured data from the transcript.

Injects resume context

`SessionStart` loads recent saved handoffs for the project and shows copyable prompts when you type continue-like phrases.

Warns about repeated command failures

`PreToolUse` checks the local error index and can inject known fixes before Claude runs a command.

Prevents infinite loops

The `Stop` hook blocks repeated tool calls with identical input and output.

Shows quota and token reports

Commands like `clauditor report`, `clauditor watch`, `clauditor sessions`, and `clauditor time` show waste, session history, and peak-hour usage.

Tracks local project knowledge

It stores errors, fixes, and file activity under `~/.clauditor/knowledge/<project>/` with confidence decay and file hotness tracking.

Optional team hub sync

`clauditor login` connects to a hub so teams can share errors, fixes, and session briefs.

How to get it

  1. 1Run
    brew install IyadhKhalfallah/clauditor/clauditor
    clauditor install
  2. 2Or via npm
    npm install -g @iyadhk/clauditor
    clauditor install
  3. 3Also works with npx (no global install)
    npx @iyadhk/clauditor install

README

clauditor

Stop Claude Code from burning through your quota in 20 minutes.

npm version CI MIT License


The problem

Every turn in a Claude Code session re-sends your entire conversation history to the API. A fresh session sends ~20k tokens per turn. A 200-turn session sends ~200k per turn. Same work, 10x more quota.

Turn    1: ██ 20k tokens
Turn   50: ██████████ 100k tokens
Turn  200: ████████████████████ 200k tokens
Turn  500: ██████████████████████████████████████████ 400k tokens

This is why your session limit gets hit in 20 minutes. Not because of a bug — because sessions grow linearly and nobody tells you to start fresh.

The solution

clauditor monitors your session size and blocks Claude when you're wasting quota, saving your progress so you can start fresh without losing context.

╔══════════════════════════════════════════════════════════════╗
║  clauditor: Session using 9x more quota than necessary      ║
╚══════════════════════════════════════════════════════════════╝

This session is burning 9x more quota per turn (170k vs ~20k tokens/turn).
Your progress has been saved and won't be lost.

Run `claude` to start a fresh session at ~20k tokens/turn instead of 170k.
In the new session, just say "continue where I left off".

When you type "continue" in the new session, clauditor shows your saved sessions and tells you exactly what to type:

╔══════════════════════════════════════════════════════════════╗
║  clauditor: 2 recent sessions found                        ║
╚══════════════════════════════════════════════════════════════╝

  1. (5m ago) Notion backfill — populating database with User Email
     → read ~/.clauditor/sessions/.../1234.md and continue where I left off

  2. (30m ago) feat/variable-agent — migrating from ResponsesApi
     → read ~/.clauditor/sessions/.../5678.md and continue where I left off

Copy one of the → lines above, or type something else to start fresh.

Install

brew install IyadhKhalfallah/clauditor/clauditor
clauditor install

Or via npm:

npm install -g @iyadhk/clauditor
clauditor install

That's it. Two commands. clauditor registers hooks into Claude Code and runs in the background. No dashboard needed. No config needed.

Also works with npx (no global install):

npx @iyadhk/clauditor install

Hooks are registered to run via npx automatically.

New hooks are auto-registered on upgrade — no need to re-run clauditor install.

Requires Node.js 20+.

Supported platforms: Claude Code CLI, VS Code extension, JetBrains extension. Does not work with Claude Code on the web (claude.ai/code).

Known limitation: The "continue" prompt block works reliably in the CLI. In the VS Code extension, the UserPromptSubmit hook may not fire consistently — context is still injected via SessionStart but Claude may not always announce it. This is a Claude Code bug, not a clauditor issue.

How it works

clauditor registers 7 hooks into Claude Code:

UserPromptSubmit — blocks before tokens are wasted

Before Claude processes your prompt, clauditor checks two things:

  1. Waste factor — if the session is burning too much quota, it blocks with exit code 2.
  2. "Continue" detection — if you type "continue", "resume", "pick up where I left off", etc., it blocks with your saved session choices and copyable prompts.
Waste factor = current tokens/turn ÷ baseline tokens/turn

  1x = efficient (fresh session)
  5x = growing
 10x = blocked — start fresh

PostToolUse — blocks during autonomous work

When Claude is working autonomously (editing files, running commands), there's no user prompt to intercept. The PostToolUse hook catches this — after each tool call, it checks the waste factor and blocks if too high.

Uses exit code 2, which Claude Code treats as a blocking error. Claude acknowledges it, writes a handoff summary, and stops.

Also detects: cache degradation, token spikes, resume anomalies, edit thrashing, and buggy Claude Code versions (2.1.69-2.1.89 have a known cache bug that burns 10-20x tokens).

PreCompact — saves context before compaction

Fires at the exact moment before Claude Code compacts your context. Saves session state as a fallback in case PostCompact doesn't fire.

PostCompact — captures Claude's summary + mechanical state

Fires after compaction. Merges Claude's own LLM-generated summary with mechanically extracted structured data (files, commits, commands) from the JSONL transcript.

SessionStart — injects previous session context

When you start a new session, clauditor reads saved handoff files for this project and injects them into Claude's context. If multiple sessions exist (last 24h), Claude presents the choice.

PreToolUse — prevents known errors

Before Claude runs a command, clauditor checks the local error index (and optionally the team hub) for previous failures with the same binary. If a known fix exists with sufficient confidence, it injects it as context — non-blocking, so Claude can adapt without being stopped.

[clauditor]: `npm run build` has failed 5 times on this project.
Last error: Module not found: Cannot resolve @/lib/db
Known fix: `npx drizzle-kit push && npm run build`

If the command succeeds after the warning, confidence increases. If it fails despite the warning, confidence decreases. The knowledge base self-corrects over time.

Stop — blocks infinite loops

When Claude repeats the same tool call 3+ times with identical input and output, the Stop hook blocks it.

Real data

From a real user's Claude Code usage over 7 days:

  TURNS  BASE   NOW   WASTE  TOKENS
  ──────────────────────────────────────────────────────────
    317   21k  417k  20.1x    73M  ████████████████████
    576   28k  401k  14.5x   116M  ███████████████
    172   23k  249k    11x    25M  ███████████
    164   26k  220k   8.6x    21M  █████████
    230   28k  218k   7.8x    31M  ████████
    ...
  ──────────────────────────────────────────────────────────
  37 sessions · 418M tokens total
  15 sessions burned 5x+ more quota than necessary

  clauditor impact
  With rotation on all sessions: 157M tokens instead of 418M
  Potential savings: 261M tokens (62% less quota)

Dashboard (optional)

clauditor watch
── clauditor ──  4 sessions + 3 subagents (last 12h)

 LAST 7 DAYS
 37 sessions · 15 burned 5x+ quota
 Worst: api/service (317 turns, 20.1x waste — 21k→417k/turn)
 With rotation: 157M tokens instead of 418M (62% savings)

 api-service (feat/variable-agent)  opus-4-6 · 239 turns

 Waste factor: 8x  BLOCKED — start a fresh session
 ██████████████████████████████
 Started at 20k/turn → now 153k/turn (8x more quota per turn)

 Cache: 98%  Turns: 239  ~$64 API est.

Peak vs off-peak analysis

clauditor time

Shows token costs by hour of day to detect if peak hours burn more quota:

  Token Usage by Hour — last 7 days
  ──────────────────────────────────────────────────────────
  10:00    98k/turn   304 turns  cache  92%  ███████████
  14:00   124k/turn   289 turns  cache  96%  ██████████████
  18:00   164k/turn   275 turns  cache  98%  ██████████████████
  ──────────────────────────────────────────────────────────
  Peak (9am-5pm):    114k avg tokens/turn
  Off-peak:          154k avg tokens/turn

All commands

CommandDescription
clauditorShow quota report (default)
clauditor installRegister hooks into Claude Code (one-time)
clauditor uninstallRemove hooks
clauditor watchLive dashboard showing waste factor
clauditor reportQuota usage report with waste bars
clauditor shareCopy-pasteable summary for social media
clauditor timeToken usage by hour of day (peak vs off-peak)
clauditor sessionsSee where your tokens went
clauditor statusQuick health check (no TUI)
clauditor impactLifetime stats
clauditor activityRecent actions log
clauditor statsHistorical usage analysis
clauditor doctorScan for cache bugs
clauditor calibrateAuto-calibrate rotation threshold
clauditor suggest-skillFind repeating workflows
clauditor knowledgeShow accumulated errors and file activity
clauditor handoff-reportMeasure information preservation of last session handoff
clauditor loginSign in to clauditor hub (opens browser, or --device for SSH)

Audit-only mode (no hooks)

Don't want clauditor to block or modify your sessions? Skip clauditor install and use it as a read-only analytics tool:

brew install IyadhKhalfallah/clauditor/clauditor
# or: npm install -g @iyadhk/clauditor
clauditor report      # see waste across all sessions
clauditor time        # peak vs off-peak token analysis
clauditor sessions    # per-session breakdown
clauditor doctor      # scan for cache bugs
clauditor share       # copy-pasteable summary

These commands read your session JSONL files directly. No hooks registered, no session modifications, no side effects.

Works alongside other tools

clauditor operates at the session boundary layer — it monitors waste and rotates sessions. Other tools work at different layers and are fully compatible:

ToolLayerWhat it doesConflicts?
HeadroomAPI proxyCompresses tool output tokens (~34% savings per turn)No — works at HTTP level
MemStackPersistent memorySQLite + vector DB for cross-session knowledgeNo — uses skills + rules
Claude Workspace OptimizerStatic workspaceAudits CLAUDE.md and memory files for bloatNo — runs before sessions
GrapeRootPer-turn contextBuilds code graph, pre-loads relevant filesNo — complementary
Hippo MemoryPersistent memoryNeuroscience-inspired memory with decayNo — different approach

You can run all of them together. clauditor handles when to rotate; the others optimize what happens within a session.

Configuration

Everything works out of the box. One config file at ~/.clauditor/config.json:

{
  "rotation": {
    "enabled": true,
    "threshold": 100000,
    "minTurns": 30
  },
  "notifications": {
    "desktop": true
  }
}
SettingDefaultDescription
rotation.enabledtrueEnable/disable session rotation
rotation.threshold100000Tokens/turn average to trigger block
rotation.minTurns30Minimum turns before blocking
notifications.desktoptrueDesktop notifications for cache issues

Created automatically on clauditor install. Edit to customize.

How it saves context

clauditor combines two methods to maximize information preservation during session rotation.

Structured handoff template

When clauditor blocks a session for rotation, it tells Claude to write its handoff in a structured format:

TASK: (what you were working on)
COMPLETED: (what's done)
IN_PROGRESS: (what's partially done, with file paths)
FAILED_APPROACHES: (what was tried and didn't work, and WHY)
DEPENDENCIES: (things that must happen in order)
DECISIONS: (choices made and why)
USER_PREFERENCES: (what the user asked for or rejected)
BLOCKERS: (unresolved issues)

This captures what only Claude knows — reasoning, rejected approaches, conditionals — in a parseable format. The parser detects structured output (2+ section headers) and falls back to prose if Claude doesn't follow the template.

Mechanical extraction

Every handoff also includes structured data extracted mechanically from the JSONL transcript:

  • Files modified and read
  • Git commits (verbatim messages)
  • Key commands and results (builds, tests, deploys)
  • Recent user messages

This data is deterministic — no LLM interpretation, no paraphrasing, no loss.

Why both?

Research shows LLM-generated summaries suffer from knowledge overwriting and semantic drift (Size-Fidelity Paradox). Mechanical extraction preserves files and commits deterministically. Claude's prose captures reasoning the transcript can't. Together they give the next session the best possible starting point.

clauditor handoff-report   # see what your last handoff contains
  Structural Coverage
  ────────────────────────────────────────────────────

  Score:  73% (11/15 structural items in handoff)

  Files modified         2/4  ██████████░░░░░░░░░░
  Commits                2/2  ████████████████████
  Files read             3/5  ████████████░░░░░░░░
  Commands               2/2  ████████████████████

Per-session storage

Each handoff is saved as a separate timestamped file:

~/.clauditor/sessions/<encoded-project-path>/<timestamp>.md

Multiple sessions in the same project don't overwrite each other. Files older than 24h are cleaned up automatically.

Session resume flow

  1. clauditor blocks your session (or /compact fires)
  2. Context is saved — structured template + mechanical data
  3. You open a new session and type "continue"
  4. clauditor blocks with your saved sessions and copyable prompts
  5. You paste the prompt — Claude reads the file and picks up where you left off

Project memory

clauditor learns from your sessions and builds per-project knowledge at ~/.clauditor/knowledge/<project>/.

Error index with confidence decay — Records failed commands and their fixes. Each error has a confidence score (0–1) that decays with a 45-day half-life. Recent errors rank above old ones. Stale errors fade naturally instead of accumulating forever.

  npm run build          conf=0.85  (confirmed, 5x)
  npx drizzle-kit push   conf=0.30  (inferred, 1x)

Noise filtering — Typo commands (command not found), transient network errors (ETIMEDOUT), and tiny error messages are filtered at capture time. Keeps the error index clean from day one.

Implicit outcome tracking — When PreToolUse warns about a command and PostToolUse sees the result, confidence adjusts automatically. Command succeeded after warning? +0.1. Failed despite warning? -0.15. Self-correcting, zero effort.

Confidence tiers — Errors are labeled confirmed (0.7+), observed (0.4+), inferred (0.2+), or stale (<0.2). Claude sees the tier in the injection, so it knows how much to trust each entry.

File tracker — Tracks edit/read counts across sessions. Identifies "hot files" (5+ edits across 3+ sessions) and injects context when Claude touches them, so it knows the file's history.

clauditor knowledge   # see accumulated errors and file activity

Team knowledge sync (optional, beta)

For teams, clauditor can optionally connect to a hub for shared knowledge:

clauditor login

Opens your browser to sign in. For SSH or headless environments:

clauditor login --device

  Visit: https://www.clauditor.ai/device
  Enter code: XPFN-8442

When connected:

  • PreToolUse queries the hub before Bash commands — team errors and fixes are shared
  • PostToolUse pushes error fragments to the hub and queries for file context
  • SessionStart pulls a compact team knowledge brief

Knowledge starts as developer-scoped and auto-promotes to team-scoped when multiple developers report the same issue. No hub required for solo use — all local features work independently.

Cross-project session handoffs

Session handoffs work across projects. If you save a session in project A and open project B, clauditor finds it. Cross-project sessions show [project-name] labels so you know where they came from.

Version-aware warnings

clauditor detects if your sessions ran on Claude Code versions 2.1.69-2.1.89, which have a confirmed prompt caching bug that causes 10-20x token consumption. The warning appears in clauditor report and via real-time hooks.

Technical details

Why sessions get expensive:

Every Claude Code API call sends: toolssystem promptCLAUDE.mdconversation history. The conversation history grows linearly. Cache makes the prefix cheap (cache_read), but the growing tail requires cache_create each turn.

API call = tools (cached) + system (cached) + history (grows every turn)

After 200 turns, the history alone can be 200k+ tokens. A fresh session resets this to near zero.

What clauditor monitors:

MetricSourceFormula
Tokens/turnJSONL usage fieldinput + output + cache_read + cache_create
BaselineFirst 5 turns of sessionAverage tokens/turn
CurrentLast 5 turns of sessionAverage tokens/turn
Waste factorDerivedcurrent ÷ baseline
Cache ratioJSONL usage fieldcache_read ÷ (input + cache_read + cache_create)

Hook communication:

HookMechanismWhy
UserPromptSubmitExit code 2 + stderrHard block — stops prompt, shows message
PostToolUseExit code 2 + stderrBlocking error — Claude acknowledges and stops
PreToolUseadditionalContextInjects known error fixes before commands
PreCompactFile writeSaves fallback state at compaction moment
PostCompactFile writeCaptures Claude's own LLM summary
SessionStartadditionalContextInjects previous session state
Stopdecision: "block"Prevents infinite loops

Limitations

  • Cannot reduce Claude Code's context assembly. We observe and advise — we don't modify what Claude Code sends to the API.
  • Cannot see quota. Anthropic doesn't expose quota data. The waste factor is a proxy based on token growth.
  • Cache reads may or may not count toward quota. The exact quota accounting for Max plan subscribers is not published.
  • Web sessions not supported. Only CLI and IDE extensions write local JSONL files.
  • Per-device only. Sessions don't sync across machines.
  • VS Code UserPromptSubmit limitation. The "continue" prompt block works in CLI but may not fire in VS Code. Context is still injected via SessionStart.

Development

git clone https://github.com/IyadhKhalfallah/clauditor.git
cd clauditor
npm install
npm test        # 275 tests
npm run build
npm link        # makes `clauditor` available globally

Legal

MIT License. Not affiliated with or endorsed by Anthropic.

  • No leaked source code was referenced or used
  • All features derived from official docs, public community discussions, and independent observation
  • "clauditor" = "Claude" + "auditor", used in a descriptive, nominative sense

Contributing

Contributions welcome. Rules:

  • No leaked source code. Do not reference or derive logic from non-public Anthropic code.
  • Attributable knowledge only. Official docs, public GitHub issues, community posts, or independent observation.
  • Clean-room implementation. If unsure about a knowledge source, don't contribute it.

License

MIT

Files in the repo

Repository payload12 top-level entries
  • .github
  • src
  • .gitignore
  • CHANGELOG.md
  • CONTRIBUTING.md
  • LICENSE
  • package-lock.json
  • package.json
  • README.md
  • tsconfig.json
  • tsup.config.ts
  • vitest.config.ts

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