Write-time code quality enforcement using Plankton — auto-formatting, linting, and Claude-powered fixes on every file edit via hooks. Use when setting up write-time formatting, linting, or auto-fix hooks on file edits.

Plankton Code Quality Skill Integration reference for Plankton (credit: @alxfazio), a write time code quality enforcement system for Claude Code. Plankton runs formatters and linters on every file edit via PostToolUse hooks, then spawns Claude subprocesses to fix violations the agent didn't catch. When to Use You want automatic formatting and linting on every file edit (not just at commit time) You need defense against agents modifying linter configs to pass instead of fixing code You want tiered model routing for fixes (Haiku for simple style, Sonnet for logic, Opus for types) You work with multiple languages (Python, TypeScript, Shell, YAML, JSON, TOML, Markdown, Dockerfile) How It Works Three Phase Architecture Every time Claude Code edits or writes a file, Plankton's multi linter.sh PostToolUse hook runs: What the Main Agent Sees Scenario Agent sees Hook exit No violations Nothing 0 All fixed by subprocess Nothing 0 Violations remain after subprocess [hook] N violation(s) remain 2 Advisory (duplicates, old tooling) [hook:advisory] ... 0 The main agent only sees issues the subprocess couldn't fix. Most quality problems are resolved transparently. Config Protection (Defense Against Rule Gaming) LLMs will modify .ruff.toml or biome.json to disable rules rather than fix code. Plankton blocks this with three layers: 1. PreToolUse hook — protect linter configs.sh blocks edits to all linter configs before they happen 2. Stop hook — stop config guardian.sh detects config changes via git diff at session end 3. Protected files list — .ruff.toml , biome.json , .shellcheckrc , .yamllint , .hadolint.yaml , and more Package Manager Enforcement A PreToolUse hook on Bash blocks legacy package managers: pip , pip3 , poetry , pipenv → Blocked (use uv ) npm , yarn , pnpm → Blocked (use bun ) Allowed exceptions: npm audit , npm view , npm publish Setup Quick Start Note: Plankton requires manual installation from its repository. Review the code before installing. No install command, no plugin config. The hooks in .claude/settings.json are picked up automatically when you run Claude Code in the Plankton directory. Per Project Integration To use Plankton hooks in your own project: 1. Copy .claude/hooks/ directory to your project 2. Copy .claude/settings.json hook configuration 3. Copy linter config files ( .ruff.toml , biome.json , etc.) 4. Install the linters for your languages Language Specific Dependencies Language Required Optional Python ruff , uv ty (types), vulture (dead code), bandit (security) TypeScript/JS biome oxlint , semgrep , knip (dead exports) Shell shellcheck , shfmt — YAML yamllint — Markdown markdownlint cli2 — Dockerfile hadolint ( = 2.12.0) — TOML taplo — JSON jaq — Pairing with ECC Complementary, Not Overlapping Concern ECC Plankton Code quality enforcement PostToolUse hooks (Prettier, tsc) PostToolUse hooks (20+ linters + subprocess fixes) Security scanning AgentShield, security reviewer agent Bandit (Python), Semgrep (TypeScript) Config protection — PreToolUse blocks + Stop hook detection Package manager Detection + setup Enforcement (blocks legacy PMs) CI integration — Pre commit hooks for git Model routing Manual ( /model opus ) Automatic (violation complexity → tier) Recommended Combination 1. Install ECC as your plugin (agents, skills, commands, rules) 2. Add Plankton hooks for write time quality enforcement 3. Use AgentShield for security audits 4. Use ECC's verification loop as a final gate before PRs Avoiding Hook Conflicts If running both ECC and Plankton hooks: ECC's Prettier hook and Plankton's biome formatter may conflict on JS/TS files Resolution: disable ECC's Prettier PostToolUse hook when using Plankton (Plankton's biome is more comprehensive) Both can coexist on different file types (ECC handles what Plankton doesn't cover) Configuration Reference Plankton's .claude/hooks/config.json controls all behavior: Key settings: Disable languages you don't use to speed up hooks volume threshold — violations this count auto escalate to a higher model tier subprocess delegation: false — skip Phase 3 entirely (just report violations) Environment Overrides Variable Purpose HOOK SKIP SUBPROCESS=1 Skip Phase 3, report violations directly HOOK SUBPROCESS TIMEOUT=N Override tier timeout HOOK DEBUG MODEL=1 Log model selection decisions HOOK SKIP PM=1 Bypass package manager enforcement References Plankton (credit: @alxfazio) Plankton REFERENCE.md — Full architecture documentation (credit: @alxfazio) Plankton SETUP.md — Detailed installation guide (credit: @alxfazio) ECC v1.8 Additions Copyable Hook Profile Set strict quality behavior: Language Gate Table TypeScript/JavaScript: Biome preferred, Prettier fallback Python: Ruff format/check Go: gofmt Config Tamper Guard During quality enforcement, flag changes to config files in same iteration: biome.json , .eslintrc , prettier.config , tsconfig.json , pyproject.toml If config is changed to suppress violations, require explicit review before merge. CI Integration Pattern Use the same commands in CI as local hooks: 1. run formatter checks 2. run lint/type checks 3. fail fast on strict mode 4. publish remediation summary Health Metrics Track: edits flagged by gates average remediation time repeat violations by category merge blocks due to gate failures

plankton-code-quality