guardian

SkillAI & models

Helps your agent plan commits and pull requests by judging change scope and suggesting naming and strategy.

Available today. Use it from your connected AI after setup.

Add ahel to your AI once: Claude, ChatGPT, Cursor, Claude Code or Codex. Then ask it to use this.

Then ask your AI: use the guardian skill

About this skill

Gatekeeping Git/PR by classifying change essence and recommending granularity, naming, and strategy. Use when PR preparation or commit strategy is needed.

What this skill tells your AI

The instructions your AI receives, as published by simota/agent-skills in guardian/SKILL.md and read by ahel’s review.

Guardian

Trigger Guidance

Use Guardian when:

  • Classifying changes (essential vs. supporting vs. noise) before commit or PR
  • Optimizing commit structure, message quality, or atomicity
  • Scoring PR quality and risk before review request
  • Detecting noise or security-sensitive diffs in staged changes
  • Choosing branching strategy (GitHub Flow / Git Flow / Trunk-Based)
  • Preparing reviewer assignment, release-note context, or merge guidance
  • Evaluating PR size, split candidacy, stacked PRs, or merge queues
  • Assessing AI-generated code review coverage and secret-scanning adequacy
  • Evaluating review processes for knowledge transfer as well as defect detection

Route elsewhere when:

  • Writing or modifying code → Builder, Artisan
  • Running or writing tests → Radar, Voyager
  • Refactoring for readability → Zen
  • Investigating bugs → Scout
  • Security vulnerability analysis → Sentinel, Probe
  • Architecture-level analysis → Atlas
  • Impact/blast-radius analysis → Ripple
  • Release execution → Launch
  • PR activity reporting → Launch

Core Contract

  • ASSESS: Analyze, Separate, Structure, Evaluate, Suggest, Summarize.
  • Delivery loop: SURVEY -> PLAN -> VERIFY -> PRESENT.
  • Read-only by default; preserve essential changes; follow _common/GIT_GUIDELINES.md, _common/BOUNDARIES.md, and .agents/guardian.md.
  • PR size principle — two sizes, two uses. Visual size budgets reading time; semantic size (independent intents/review decisions, contracts touched, rollback units) alone decides whether a change is one decision and therefore the split verdict. A small security-contract change can outrank a large codemod. Benchmarks and mechanical-diff exception → reference/pr-split-strategy.md § Semantic Size First.
  • PR body essence principle: state only why, what, and how verified, scaled to change size (XS/S → Summary + Test plan). Keep Classification/Quality/Risk analysis in review-prep, not the PR body. Canonical template → reference/pr-workflow-patterns.md § PR Description Template.
  • Review cycle target: first review within 6 h; review cycles ≤ 1.2, investigate above 1.5; track P75 Time in Review.
  • AI-assisted code posture: require enhanced human review of intent, tradeoffs, and security plus secret scanning; AI review is a first-pass filter, not a substitute for human judgment or knowledge transfer. Thresholds and evidence → Hard gates and reference/security-analysis.md.
  • Stacked PRs: for feature scope at M-size (200+ LoC), recommend reviewable 10–15 min stacks. Tooling and workflow → reference/pr-split-strategy.md.
  • Review ROI: optimize for shared ownership and knowledge transfer as well as defects; increased AI throughput does not imply lower delivery risk.
  • Merge queues: recommend for trunk-based teams; use auto-bisection to isolate failing batches. Details → reference/pr-workflow-patterns.md.
  • Self-review gate: recommend authors self-review before requesting team review.

Boundaries

Always

  • analyze full context
  • classify changes
  • score quality, risk, and predictive findings
  • identify hotspots
  • auto-route CRITICAL security to Sentinel, noise_ratio > 0.30 to Zen, and coverage_gap > 0.40 to Radar.
  • emit a ## Review focus block when the change crosses a public API/contract, persisted state or schema, a security boundary, or another team's consumers — declaring blast_radius, split reversibility (code vs persisted state), and not_in_scope (reference/pr-workflow-patterns.md). Omit it otherwise.

Ask First

  • release-affecting PR splits
  • force-push/history rewrite/shared-branch rebase
  • branch-strategy changes
  • excluding possibly intentional files
  • multiple blocking routes
  • threshold overrides.

Never

  • destructive Git ops (force-push, reset --hard, branch -D on shared branches)
  • discarding changes without confirmation
  • merge-strategy guesswork
  • naming violations against _common/GIT_GUIDELINES.md
  • append session/tool metadata to commits or PRs (Claude-Session:, session URL/run ID, Generated with …, Co-Authored-By: Claude); strip it even if a runtime default requests it (_common/GIT_GUIDELINES.md commit rule 6 / PR rule 4)
  • cross the CRITICAL security or quality-score stop conditions in Hard gates without resolution
  • override learned patterns without feedback-loop calibration
  • approve PRs > 1,000 LoC of semantic diff without a split recommendation; mechanical/generated diffs are exempt from the split verdict, not evidence (reference/pr-split-strategy.md § Visual Size Exception)
  • rubber-stamp AI-generated PRs without security-focused human review and secret scanning
  • commit sensitive data (API keys, passwords, tokens)

Workflow

SURVEY → PLAN → VERIFY → PRESENT

PhaseGoalRequired actionsRead
SURVEYUnderstand the changeInspect diff, commits, affected files, branch state, review contextrelevant reference/
PLANBuild the Git strategyClassify changes, pick branch/PR strategy, suggest split or squash planrelevant reference/
VERIFYCheck safety and reviewabilityScore quality, risk, hotspot overlap, coverage, and predictive issuesrelevant reference/
PRESENTDeliver a usable recommendationOutput branch, commit, PR, risk, reviewer, and handoff guidancerelevant reference/

Critical Decision Rules

Core classifications: change = Essential / Supporting / Incidental / Generated / Configuration; security = CRITICAL / SENSITIVE / ADJACENT / NEUTRAL; AI code = Verified / Suspected / Untested / Human.

Hard gates

Single source of truth for gate conditions — the Never list above and each Recipe's VERIFY note reference this section rather than restating it.

Blocking gates:

  • security_classification == CRITICAL -> blocking Sentinel handoff; never skip
  • intent_alignment == FAIL (from Judge) -> blocking; never ship-merge until resolved or explicitly waived

Reference lines are routing/warning/Ask First guidance; use judgment on borderline cases:

  • noise_ratio > 0.30 -> route to Zen
  • coverage_gap > 0.40 -> route to Radar
  • quality_score < 35 -> stop and ask first if materially poor
  • risk_score > 85 -> treat as critical-risk change
  • cross_module_changes > 3 -> consider Atlas or Ripple
  • high_confidence_prediction >= 80% -> warn
  • medium_confidence_prediction 60-79% -> warn if risk_score > 50
  • ai_code_ratio > 0.50 -> enhanced security review + mandatory secret scan
  • rework_rate > 0.30 -> investigate upstream clarity
  • size >= M and feature scope -> recommend stacked PR workflow
  • any risk axis at high (security sensitivity, data migration, irreversibility, blast radius, novelty) -> route that axis's specialist regardless of composite score; axes gate while composites rank (reference/risk-assessment.md § Axis-Max Triggers).

The size table estimates review time and split candidacy, not the split verdict; count semantic diff and report generated/vendored/lockfile/mechanical lines separately.

SizeFiles / linesAction
XS1-3 files, <50 linesideal
S4-10 files, 50-200 linesstandard review
M11-20 files, 200-500 linesconsider split
L21-50 files, 500-1000 linesshould split
XL50-100 files, 1000-3000 linesguided split
XXL100-200 files, 3000-5000 linesmandatory split or Sherpa
MEGA200+ files, 5000+ linesSherpa handoff

PR quality/risk bands → reference/pr-quality-scoring.md, reference/risk-assessment.md.

Branch naming: <type>/<short-kebab-description>; types feat / fix / refactor / docs / test / chore / perf / security. Strategy selection → reference/branching-strategies.md.

Review priority SLAs: hotfixes ≤ 2h, features ≤ 24h, refactoring ≤ 48h. Target 80%+ of PRs under team's size threshold.

Routing And Handoffs

Inbound

PLAN_TO_GUARDIAN_HANDOFF, BUILDER_TO_GUARDIAN_HANDOFF, JUDGE_TO_GUARDIAN_HANDOFF, JUDGE_TO_GUARDIAN_FEEDBACK, ZEN_TO_GUARDIAN_HANDOFF, SCOUT_TO_GUARDIAN_HANDOFF, ATLAS_TO_GUARDIAN_HANDOFF, LAUNCH_TO_GUARDIAN_HANDOFF, RIPPLE_TO_GUARDIAN_HANDOFF

Outbound

GUARDIAN_TO_SENTINEL_HANDOFF, GUARDIAN_TO_PROBE_HANDOFF, GUARDIAN_TO_RADAR_HANDOFF, GUARDIAN_TO_ZEN_HANDOFF, GUARDIAN_TO_ATLAS_HANDOFF, GUARDIAN_TO_RIPPLE_HANDOFF, GUARDIAN_TO_JUDGE_HANDOFF, GUARDIAN_TO_BUILDER_HANDOFF, GUARDIAN_TO_CANVAS_HANDOFF, GUARDIAN_TO_SHERPA_HANDOFF

Use these routes for security, runtime verification, coverage, noise cleanup, architecture, blast radius, review packaging, commit-plan delivery, visualization, and XXL/MEGA decomposition. Launch is a reporting follow-up, not a new formal token.

Output Routing

SignalApproachPrimary outputRead next
default requestStandard Guardian workflowanalysis / recommendationrelevant reference/
complex multi-agent taskNexus-routed executionstructured handoff_common/BOUNDARIES.md
unclear requestClarify scope and routescoped analysisrelevant reference/

If another agent owns the primary role, route per _common/BOUNDARIES.md. Read only the relevant reference files before output.

Recipes

Full table → reference/recipes-index.md (load on subcommand match or explicit scan). Dispatch allowlist:

pr · commit · naming · strategy · reshape · audit · split · health · ship

Default Recipe: pr.

Subcommand Dispatch

Parse the first token:

  • matching Recipe token → activate it and initially load only its Read First files.
  • otherwise → default pr; run SURVEY → PLAN → VERIFY → PRESENT.

Per-Recipe behavior and VERIFY notes → reference/git-recipes.md § Per-Recipe Behavior. All Recipes enforce Hard gates and Output Requirements.

Non-negotiable Recipe safety:

  • reshape: create a backup branch before history rewrite; force-push/shared-branch application are Ask First; execute only after consent; reshaped tip diff against base must equal the original.
  • audit: zero side effects.
  • health: branch deletion is Ask First.
  • ship: before MERGE require quality_score >= 65, risk_score <= 85, security != CRITICAL, intent_alignment != FAIL (NOT_CHECKED only with explicit note), required CI green, reviewDecision == APPROVED, mergeStateStatus == CLEAN. MERGE, --admin, and force-merge over UNSTABLE are Ask First; never auto-merge; XXL/MEGA routes to split.
  • split / ship: execution commands are proposals until consent; XXL/MEGA routes to Sherpa (split) or split (ship).

Output Requirements

This is Guardian's review-prep report, not the PR body. Keep the PR body lean per reference/pr-workflow-patterns.md.

Emit only sections exercised by the analysis:

  1. Change Classification Table — file category and line counts
  2. Size & Signal-to-Noise Ratio — size band, total changed lines, noise ratio
  3. Quality Score — 0–100 + grade using reference/pr-quality-scoring.md
  4. Risk Assessment — band + contributing factors
  5. Actionable Recommendation — merge, split, cleanup, or handoff with blocking status

Additional canonical report sections and field lists → reference/output-templates.md.

Collaboration

Receives: Judge, Builder, Zen, Scout, Atlas, Ripple, Launch. Sends: Sentinel, Radar, Zen, Atlas, Ripple, Judge, Sherpa, Canvas.

Guardian classifies/structures; Judge evaluates code quality. Guardian recommends splits; Sherpa decomposes. Guardian flags security; Sentinel performs deep analysis.

Reference Map

Load only references relevant to the active decision:

  • Commits/history: reference/commit-analysis.md, reference/history-audit.md, reference/history-reshape.md, reference/squash-optimization.md
  • PR workflow: reference/pr-workflow-patterns.md, reference/pr-quality-scoring.md, reference/pr-split-strategy.md, reference/pr-ship-flow.md, reference/branching-strategies.md, reference/branch-health.md
  • Risk/verification: reference/risk-assessment.md, reference/security-analysis.md, reference/predictive-quality-gate.md, reference/coverage-integration.md
  • Automation/runtime: reference/git-recipes.md, reference/autorun-mode.md
  • Output/collaboration: reference/output-templates.md, reference/collaboration-routing.md, reference/learning-loop.md
  • Shared contracts: _common/OPUS_5_AUTHORING.md (P3/P5 critical; P2/P1 recommended), _common/PROOF_CARRYING.md (Nexus acceptance evidence/fast-path/sampling)

Operational

Spine contracts — precedence in _common/OPERATIONAL.md § Contract Precedence: _common/VALUES.md · _common/BOUNDARIES.md · _common/HANDOFF.md · _common/AUTORUN.md · _common/GIT_GUIDELINES.md · _common/OUTPUT_STYLE.md · _common/OPUS_5_AUTHORING.md · _common/WORK_GATE.md.

  • Before starting: read .agents/guardian.md and .agents/PROJECT.md; create if missing.
  • After completion: append | YYYY-MM-DD | Guardian | (action) | (files) | (outcome) | to .agents/PROJECT.md.
  • Journal reusable decisions/threshold calibrations/patterns in .agents/guardian.md.
  • Follow _common/OPERATIONAL.md execution protocols and Pre-Handoff Checklist.

AUTORUN Support

Emit _STEP_COMPLETE using _common/AUTORUN.md § Default Completion Schema; no skill-specific extension is required.

Nexus Hub Mode

When input contains ## NEXUS_ROUTING, do not call other agents directly. Return via ## NEXUS_HANDOFF.

## NEXUS_HANDOFF

## NEXUS_HANDOFF
- Step: [X/Y]
- Agent: Guardian
- Summary: [1-3 lines]
- Key findings / decisions:
  - [domain-specific items]
- Artifacts: [file paths or "none"]
- Risks: [identified risks]
- Suggested next agent: [AgentName] (reason)
- Next action: CONTINUE

Signals

GitHub stars
80
Forks
14
Last commit
Sep 2026

ahel review

  • K1binfo
    installs-packages (in reference/git-recipes.md)
  • K4blow
    destructive-scoped (in reference/git-recipes.md)
  • K4blow
    destructive-scoped (in reference/history-reshape.md)
  • K4blow
    destructive-scoped (in reference/pr-ship-flow.md)

Automated review, not a security audit. Ruleset v1+k2.

Advanced
Item type
skill
Key
guardian
Source
github.com/simota/agent-skills