Claude Code Quality Hooks

Detect and prevent lazy rewrites, skipped reads, and untested commits.

667 hooks 9,200+ tests 800+ hours tested

The problem is real. Analysis of 6,852 Claude Code sessions found code read counts dropped from 6.6x to 2x per edit, and full-file rewrites increased significantly. (Source: The Register, April 2026)

Quick Install

Install all quality hooks with one command:

npx cc-safe-setup --install-example overwrite-guard
npx cc-safe-setup --install-example full-rewrite-detector
npx cc-safe-setup --install-example diff-size-guard
npx cc-safe-setup --install-example commit-quality-gate
npx cc-safe-setup --install-example push-requires-test-pass
npx cc-safe-setup --install-example pre-compact-checkpoint

What Each Hook Does

Hook	Detects	Action
`overwrite-guard`	Writing to existing files without reading first	Warning
`full-rewrite-detector`	Rewriting >80% of a file when partial edit would suffice	Warning
`diff-size-guard`	Too many files changed without committing	Warning / Block
`commit-quality-gate`	Empty or vague commit messages	Block
`push-requires-test-pass`	Pushing without running tests	Block
`pre-compact-checkpoint`	Context compaction about to happen	Auto-save

Why Quality Hooks Matter

Claude Code can produce excellent work, but it can also take shortcuts:

Read 2x instead of 6.6x — editing files without fully understanding them
Full rewrites — replacing entire files when a 3-line change would suffice
Skipping tests — claiming "done" without verification
Losing work — context compaction erasing knowledge of recent edits

Hooks don't fix the model. They provide a safety net that catches quality issues before they reach your codebase.

Customize Thresholds

# diff-size-guard: change file count thresholds
export CC_DIFF_WARN=5    # warn at 5+ files changed
export CC_DIFF_BLOCK=20  # block at 20+ files changed

Find More Hooks

# Search by keyword
npx cc-safe-setup --examples quality
npx cc-safe-setup --examples overwrite
npx cc-safe-setup --examples diff
npx cc-safe-setup --examples commit

Or use the Hook Selector to get a personalized recommendation in 5 questions.

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