execution-guardian

id	execution-guardian
name	execution-guardian
type	skill
version	1.0.0
created	20/03/2026
modified	20/03/2026
status	active
metadata	{"author":"NodeJS-Starter-V1","version":"1.0.0","locale":"en-AU"}
description	>-
context	fork

Execution Guardian - Pre-Execution Governance

Dynamic validation gates and risk assessment for operations that could harm system integrity. Evaluates blast radius, reversibility, and confidence before allowing execution to proceed.

Description

Provides a pre-execution safety layer that auto-detects operation types, generates prerequisite validation gates, scores risk and confidence, and produces structured error output when operations are blocked. Complements the Council of Logic (code quality) with operation safety assessment.

When to Apply

Positive Triggers

• Destructive operations: Database migrations, file deletions, git reset, DROP TABLE, rm -rf
• Multi-layer changes: Modifications spanning frontend + backend + database in a single operation
• Auth/security changes: JWT secret rotation, RBAC permission changes, CORS policy updates, OAuth config
• Payment/billing changes: Pricing logic, subscription tiers, billing calculations
• API contract changes: Breaking changes to endpoint signatures, response shapes, error codes
• Deployment operations: Production deployments, infrastructure changes, environment variable updates
• Data migrations: Schema changes with existing data, column renames, type changes
• User mentions: "risk", "safe to proceed", "prerequisite", "validation gate", "confidence"

Negative Triggers (Delegate to Other Systems)

• Code quality review → council-of-logic
• Phase sequencing and workflow → genesis-orchestrator
• Architecture drift or dead code → system-supervisor
• Runtime error handling → error-taxonomy
• Exploration or read-only operations → No governance needed (EXPLORATION mode)
• Pure strategy/planning → No gates needed (STRATEGY mode)

---

Dynamic Validation Gates

Operation Type Auto-Detection

Scan the proposed operation and classify it into one or more operation types:

Operation Type	Detection Signals	Default Risk
DATABASE_MIGRATION	Alembic revision, ALTER TABLE, DROP, schema changes	HIGH
AUTH_CHANGE	JWT config, RBAC rules, password hashing, session management	HIGH
API_CONTRACT_CHANGE	Endpoint signature change, response model change, status code change	MEDIUM
DEPLOYMENT	Docker push, vercel deploy, environment variable changes	HIGH
DESTRUCTIVE_FILE_OP	rm -rf, git reset --hard, git clean -f, file overwrites	HIGH
SECURITY_CHANGE	CORS policy, CSP headers, rate limit config, secret rotation	HIGH
MULTI_LAYER_CHANGE	Changes in 2+ of: apps/web/, apps/backend/, scripts/, docker-compose.yml	MEDIUM
DEPENDENCY_CHANGE	pnpm add, uv add, major version bumps, removing packages	LOW
CONFIG_CHANGE	next.config, pyproject.toml, tsconfig.json, .env files	LOW

Gate Generation

For each detected operation type, generate prerequisite gates. Gates are checks that must pass before execution proceeds.

DATABASE_MIGRATION Gates

GATE: Backup exists or migration is reversible
  CHECK: Verify downgrade() function exists in Alembic revision
  BLOCKING: YES

GATE: No data loss in migration
  CHECK: Scan for DROP COLUMN, DROP TABLE, ALTER TYPE without data preservation
  BLOCKING: YES

GATE: Migration tested locally
  CHECK: uv run alembic upgrade head (on local database)
  BLOCKING: YES

AUTH_CHANGE Gates

GATE: No secret exposure in code
  CHECK: Grep for hardcoded secrets, JWT keys, API keys in diff
  BLOCKING: YES

GATE: Existing sessions handled
  CHECK: Verify session invalidation strategy for JWT secret rotation
  BLOCKING: YES

GATE: Auth tests pass
  CHECK: uv run pytest tests/test_auth.py
  BLOCKING: YES

API_CONTRACT_CHANGE Gates

GATE: Breaking change documented
  CHECK: Verify changelog entry or API version bump
  BLOCKING: NO (warning only)

GATE: Frontend contract updated
  CHECK: Verify corresponding Zod schema change in apps/web/
  BLOCKING: YES

GATE: API tests pass
  CHECK: uv run pytest tests/test_api_*.py
  BLOCKING: YES

DESTRUCTIVE_FILE_OP Gates

GATE: Files are not uncommitted work
  CHECK: git status — verify target files are committed or backed up
  BLOCKING: YES

GATE: No shared resources affected
  CHECK: Verify files are not imported/referenced by other modules
  BLOCKING: YES

DEPLOYMENT Gates

GATE: All tests pass
  CHECK: pnpm turbo run test
  BLOCKING: YES

GATE: Type checks pass
  CHECK: pnpm turbo run type-check
  BLOCKING: YES

GATE: No secrets in build output
  CHECK: Scan build artifacts for .env patterns
  BLOCKING: YES

SECURITY_CHANGE Gates

GATE: Change follows OWASP guidelines
  CHECK: Reference input-sanitisation or csrf-protection skill
  BLOCKING: NO (advisory)

GATE: Security tests pass
  CHECK: uv run pytest tests/ -k "security or auth"
  BLOCKING: YES

MULTI_LAYER_CHANGE Gates

GATE: API contract consistency
  CHECK: Backend response models match frontend Zod schemas
  BLOCKING: YES

GATE: Cross-layer tests pass
  CHECK: pnpm turbo run test (full suite)
  BLOCKING: YES

DEPENDENCY_CHANGE Gates

GATE: No known vulnerabilities
  CHECK: pnpm audit / uv pip audit
  BLOCKING: NO (warning for non-critical)

GATE: Peer dependency compatibility
  CHECK: pnpm install --dry-run succeeds
  BLOCKING: YES

CONFIG_CHANGE Gates

GATE: Config syntax valid
  CHECK: Validate JSON/TOML/YAML syntax
  BLOCKING: YES

GATE: Environment variables documented
  CHECK: New variables added to .env.example
  BLOCKING: NO (warning)

---

Risk Scoring Engine

Three Dimensions

Each operation is scored across three dimensions:

Dimension	LOW (1)	MEDIUM (2)	HIGH (3)
Blast Radius	Single file/function	Single service/layer	Multiple services or shared infrastructure
Reversibility	Easily undone (git revert, config rollback)	Requires manual steps (data restore, migration rollback)	Irreversible or extremely costly to reverse
Confidence	Well-understood pattern, high test coverage	Partially tested, some unknowns	Novel pattern, low coverage, complex domain

Composite Risk Calculation

composite_score = max(blast_radius, reversibility, confidence)

Composite Score	Risk Level	Required Response
1	LOW	Proceed. Log the operation.
2	MEDIUM	Require user approval before execution. State the risk clearly.
3	HIGH	Mandatory review. Require rollback plan. Block until approval received.

Risk-Appropriate Responses

LOW Risk:

[GUARDIAN: LOW RISK] Proceeding with {operation}.
Gates passed: {list}. No rollback plan required.

MEDIUM Risk:

[GUARDIAN: MEDIUM RISK] {operation} requires approval.
Blast radius: {assessment}
Reversibility: {assessment}
Confidence: {assessment}
Approval required before proceeding.

HIGH Risk:

[GUARDIAN: HIGH RISK] {operation} blocked pending review.
Blast radius: {assessment}
Reversibility: {assessment}
Confidence: {assessment}

Rollback Plan:
1. {step 1}
2. {step 2}
3. {step 3}

Approval required. Respond with "proceed" to continue.

---

Confidence Scoring

Confidence is scored 0-100% based on four factors:

Factor	Weight	High Confidence	Low Confidence
Pattern Novelty	30%	Well-known pattern used elsewhere in codebase	First-time pattern, no precedent
Test Coverage	30%	Relevant tests exist and pass	No tests cover this path
Domain Complexity	20%	Simple CRUD, config change	Auth, payment, distributed state
Change Scope	20%	Single file, < 50 lines	5+ files, 200+ lines

Confidence Thresholds

Range	Label	Action
80-100%	High	Proceed with standard gates
50-79%	Moderate	Require explicit approval
0-49%	Low	Recommend spike/prototype first, or request additional review

---

Structured Error Format

When the Guardian blocks an operation, output uses this format. This is distinct from error-taxonomy (which handles runtime API errors). Guardian errors are governance-level blocking decisions.

ERROR: {What failed or was blocked}
CAUSE: {Why the gate failed or risk is too high}
RISK:  {LOW | MEDIUM | HIGH} — {one-line risk summary}
FIX:   {Specific action to resolve the block}
BLOCKING: {YES | NO}

Examples

See references/error-format.md for complete examples per operation type.

BLOCKING Classification

BLOCKING	Meaning	When Used
YES	Operation cannot proceed until resolved	Data loss risk, security vulnerability, test failure
NO	Warning only — operation may proceed	Documentation missing, advisory best practice

---

Self-Healing Retry

When BLOCKING: NO and risk is LOW:

1. Apply the suggested FIX automatically
2. Re-run the failed gate
3. If pass → proceed
4. If fail again → escalate to BLOCKING: YES

Self-healing is never applied to:

• BLOCKING: YES gates
• MEDIUM or HIGH risk operations
• Security-related gates
• Database migration gates

---

Integration Points

Council of Logic

Council Member	Feeds Into	How
Turing (complexity)	Confidence scoring	High complexity = lower confidence
Von Neumann (architecture)	Blast radius assessment	Multi-service = higher blast radius
Shannon (compression)	Guardian output format	Structured, compressed error format

Boundary: Council validates code quality; Execution Guardian validates operation safety.

Genesis Orchestrator

• Phase boundaries trigger gate re-evaluation
• Guardian respects phase-locked execution (does not skip ahead)
• Section completion gates align with Guardian's deployment gates

Verification Agent

• LOW risk → standard verification
• MEDIUM risk → verification + regression tests
• HIGH risk → comprehensive verification + manual review recommendation

Execution Modes

• EXPLORATION: Guardian off
• BUILD: Standard gates, approval for MEDIUM+
• SCALE: Full gates, rollback plans required for MEDIUM+
• STRATEGY: Guardian off

---

Anti-Patterns

Pattern	Problem	Correct Approach
Gating every file edit	Over-governance, kills momentum	Only gate destructive/multi-layer/security ops
Skipping gates because "it's just a small change"	Small changes to auth/security can be catastrophic	Gate based on operation type, not change size
Blocking on advisory warnings in BUILD mode	Momentum loss	Advisory = BLOCKING: NO, proceed with warning
Applying self-healing to security gates	Could mask real vulnerabilities	Self-healing only for LOW risk, non-security gates
Generating rollback plans for LOW risk ops	Token waste, over-engineering	Rollback plans for HIGH risk only (MEDIUM in SCALE mode)

Checklist

• Operation type correctly auto-detected
• Prerequisite gates generated for all detected types
• Risk scored across blast radius, reversibility, and confidence
• Composite risk level drives appropriate response
• Structured error format used for all blocks (ERROR / CAUSE / RISK / FIX / BLOCKING)
• Self-healing only applied to BLOCKING: NO + LOW risk
• Council of Logic feeds into confidence and blast radius
• Mode-appropriate governance (BUILD vs SCALE intensity)
• Rollback plan present for HIGH risk operations

Response Format

[AGENT_ACTIVATED]: Execution Guardian
[MODE]: {EXPLORATION | BUILD | SCALE | STRATEGY}
[OPERATION]: {detected operation type(s)}
[RISK]: {LOW | MEDIUM | HIGH}
[STATUS]: {gates_passed | approval_required | blocked}

{gate results, risk assessment, or structured error}

[NEXT_ACTION]: {proceed | await approval | apply fix | escalate}

Australian Localisation (en-AU)

• Date Format: DD/MM/YYYY
• Currency: AUD ($)
• Spelling: colour, behaviour, optimisation, analyse, centre, authorisation
• Tone: Direct, professional — state risks clearly without hedging