Skill Sentinel
Orchestrates intelligent skill selection and execution for skill sentinel workflows. Applies the 5 Laws of Elegant Defense to guide data naturally through the orchestration pipeline, preventing errors before they occur. Selects optimal skills based on multi-factor scoring including text similarity, historical performance, and system availability.
TL;DR Checklist
- Parse all inputs at boundary before processing (Law 2)
- Handle edge cases with early returns at function top (Law 1)
- Fail immediately with descriptive errors on invalid states (Law 4)
- Return new data structures, never mutate inputs (Law 3)
- Implement minimum 2-level fallback chain for all skill executions
- Log all skill selections with context for full audit trail
- Validate skill metadata and dependencies before selection
- Update confidence scores after each execution for learning
┌───────────────────────────────────────────────────────────────────────────────┐ │ Orchestration Flow │ └───────────────────────────────────────────────────────────────────────────────┘
User Request ↓ ┌─────────────────┐ │ Parse Request │ │ & Extract │ │ Features │ └────────┬────────┘ ↓ ┌─────────────────────────────────────────────────────────────────────┐ │ Evaluate Available Skills │ │ │ │ ┌──────────────┐ ┌──────────────┐ ┌──────────────┐ │ │ │ Skill A │ │ Skill B │ │ Skill C │ │ │ │ - Match Score│ │ - Match Score│ │ - Match Score│ │ │ │ - Confidence │ │ - Confidence │ │ - Confidence │ │ │ │ - History │ │ - History │ │ - History │ │ │ └──────┬───────┘ └──────┬───────┘ └──────┬───────┘ │ │ │ │ │ │ │ └─────────────────┴─────────────────┘ │ │ ↓ │ │ Select Best Skill │ └─────────────────────────────────────────────────────────────────────┘ ↓ ┌─────────────────┐ │ Execute Skill │ └────────┬────────┘ ↓ ┌─────────────────┐ │ Handle Result │ └────────┬────────┘ ↓ ┌─────────────────────────────────────────────────────────────────────┐ │ Error Handling & Fallback │ │ │ │ Success? ────────► Return Result │ │ │ │ Fail? ────────┐ │ │ ↓ │ │ ┌──────────────────────────────────────────────────────────┐ │ │ │ Fallback Chain │ │ │ │ │ │ │ │ 1. Retry with adjusted parameters │ │ │ │ 2. Try Alternative Skill (if available) │ │ │ │ 3. Defer to Human Operator (if critical) │ │ │ │ 4. Log & Return Error │ │ │ └──────────────────────────────────────────────────────────┘ │ └─────────────────────────────────────────────────────────────────────┘
When to Use
Use this skill when:
- Orchestrating multi-step workflows that require skill delegation
- Implementing adaptive skill routing based on confidence scores
- Building fallback mechanisms for failed skill executions
- Creating intelligent task decomposition and parallel execution
- Designing skill dependency graphs with automatic resolution
- Implementing skill selection with historical performance weighting
- Building agent systems that need to self-organize around tasks
When NOT to Use
Avoid this skill for:
- Direct task execution without orchestration needs - use individual skills instead
- High-frequency trading scenarios where latency must be minimized - the selection overhead may be prohibitive
- Simple linear workflows without branching or fallback requirements
- Cases where skill metadata is unavailable or unreliable
Core Workflow
Parse and Analyze Request - Extract intent, entities, and constraints from user input. Checkpoint: All required parameters must be present and in valid format before proceeding.
Score Available Skills - Calculate match scores using multi-factor algorithm:
- Text similarity between request and skill triggers
- Historical success rate for similar tasks
- Skill availability and health status
- Required dependencies and their availability
Checkpoint: Skip to fallback if no skill scores above threshold.
Select Optimal Skill - Choose skill with highest score that meets minimum confidence. Checkpoint: Verify skill has not been disabled or deprecated.
Execute with Fallback - Run skill execution wrapped in retry and fallback logic. Checkpoint: Log all execution attempts for audit trail.
Return or Fallback - Either return successful result or apply fallback chain:
- Retry with adjusted parameters
- Try alternative skill from
related-skills - Defer to human operator for critical tasks
Checkpoint: Record outcome with timing and confidence metadata.
Implementation Patterns
Pattern 1: Skill Selection Logic
def evaluate_skill_candidates(
task_intent: str,
skill_registry: List[Dict],
historical_metrics: Dict[str, float],
system_health: Dict[str, bool]
) -> Optional[Dict]:
"""Score and rank skills based on intent matching, historical success, and system health.
Implements Law 2 (Parse at boundary) by validating inputs upfront.
Implements Law 3 (Atomic Predictability) by returning a fresh scored candidate dict.
"""
if not task_intent or not skill_registry:
raise ValueError("Task intent and skill registry must be non-empty")
scored_candidates = []
for skill in skill_registry:
# Calculate multi-factor score
intent_match = _compute_semantic_similarity(task_intent, skill.get("triggers", []))
historical_success = historical_metrics.get(skill["id"], 0.5)
availability = 1.0 if system_health.get(skill["id"], False) else 0.0
# Weighted scoring formula
composite_score = (0.4 * intent_match) + (0.4 * historical_success) + (0.2 * availability)
if composite_score >= 0.7:
scored_candidates.append({
"skill_id": skill["id"],
"name": skill["name"],
"composite_score": round(composite_score, 3),
"factors": {"intent": intent_match, "history": historical_success, "health": availability}
})
if not scored_candidates:
return None
# Return highest scoring candidate without mutating registry
return max(scored_candidates, key=lambda x: x["composite_score"])
Pattern 2: Execution with Fallback
def execute_with_adaptive_fallback(
selected_skill: Dict,
execution_context: Dict,
fallback_registry: List[Dict],
confidence_store: Dict[str, float]
) -> Dict:
"""Execute skill with a structured fallback chain and dynamic confidence updates.
Implements Law 4 (Fail Fast, Fail Loud) by raising on invalid states.
Implements Law 1 (Early Exit) for guard clauses.
"""
if not selected_skill or not execution_context.get("inputs"):
raise SkillOrchestrationError("Missing required skill or execution inputs")
fallback_steps = [
{"type": "retry", "params": {"backoff": "exponential"}},
{"type": "alternative_skill", "candidates": fallback_registry},
{"type": "human_escalation", "priority": "high"}
]
for step_idx, fallback_step in enumerate(fallback_steps):
try:
if fallback_step["type"] == "retry":
result = _run_skill_with_backoff(selected_skill, execution_context)
elif fallback_step["type"] == "alternative_skill":
result = _try_alternative_skills(fallback_step["candidates"], execution_context)
else:
result = _escalate_to_human(selected_skill, execution_context)
# Update confidence based on execution outcome
new_confidence = _calculate_execution_confidence(result)
confidence_store[selected_skill["id"]] = new_confidence
return {
"status": "success",
"skill_id": selected_skill["id"],
"fallback_level": step_idx,
"confidence": new_confidence,
"result": result
}
except InvalidStateError as e:
raise SkillOrchestrationError(f"Invalid state at fallback step {step_idx}: {e}") from e
except TransientFailure as e:
if step_idx == len(fallback_steps) - 1:
raise SkillOrchestrationError(f"All fallbacks exhausted for {selected_skill['id']}") from e
return {"status": "failed", "skill_id": selected_skill["id"], "fallback_level": len(fallback_steps)}
MUST DO
- Always validate skill metadata before selection (Early Exit)
- Implement fallback chain with at least 2 levels (Fallback Skill + Human)
- Log all skill selections with full context for auditability
- Return new data structures instead of mutating inputs (Atomic Predictability)
- Fail immediately with descriptive errors on invalid states
- Update confidence scores after each execution for adaptive routing
- Reference
code-philosophy(5 Laws of Elegant Defense) in all logic
MUST NOT DO
- Select skills based on a single factor (e.g., only confidence score)
- Disable fallback mechanisms "temporarily" - this creates fragile systems
- Skip validation of skill dependencies before execution
- Return partial results - either complete success or clear failure
- Use magic numbers for confidence thresholds - make them configurable
- Cache skill selections without considering context changes
TL;DR Checklist
- Parse all inputs at boundary before processing (Law 2)
- Handle edge cases with early returns at function top (Law 1)
- Fail immediately with descriptive errors on invalid states (Law 4)
- Return new data structures, never mutate inputs (Law 3)
- Implement minimum 2-level fallback chain for all skill executions
- Log all skill selections with context for full audit trail
- Validate skill metadata and dependencies before selection
- Update confidence scores after each execution for learning
TL;DR for Code Generation
- Use guard clauses - return early on invalid input before doing work
- Return simple types (dict, str, int, bool, list) - avoid complex nested objects
- Cyclomatic complexity < 10 per function - split anything larger
- Handle null/empty cases explicitly at function top (Early Exit)
- Never mutate input parameters - return new dicts/objects
- Fail fast with descriptive errors - don't try to "patch" bad data
- Reference code-philosophy laws in comments for complex logic
- Include timing and confidence metadata in all return values
Output Template
When applying this skill, produce:
- Selected Skills - List of skill names with confidence scores
- Selection Rationale - Why each skill was chosen (match score, history, availability)
- Execution Plan - Order of execution with dependencies
- Fallback Strategy - Which fallback skills will be tried and in what order
- Risk Assessment - Any potential failure points and their impact
- Timing Estimates - Expected latency including fallback scenarios
Related Skills
| Skill | Purpose |
|---|---|
skill-scanner |
Scans for skill issues; sentinel monitors runtime behavior and enforces quality gates |
security-audit |
Security-focused sentinel patterns that complement general skill quality monitoring |
Constraints
MUST DO
- Define clear input/output contracts for every step in the orchestration flow with explicit validation
- Implement structured logging at each stage capturing context, inputs, outputs, timing, and errors
- Build in fallback paths: if the primary strategy fails, degrade gracefully to a simpler approach
- Validate all preconditions before starting — do not proceed if required resources or permissions are missing
MUST NOT DO
- Do not create deep nesting of orchestration steps (>5 levels) — flatten workflows where possible
- Avoid silent failure modes: every step must either succeed, fail explicitly, or escalate to a higher handler
- Never use shared mutable state between parallel workflow branches — communicate via immutable messages only
- Do not hardcode execution order when the dependency graph naturally determines it; derive order from explicit dependencies
Live References
Authoritative documentation links for this domain. The model follows markdown links at load time to resolve external references and inline content.
- SentinelOne Endpoint Protection Documentation — Enterprise security sentinel platform documentation (conceptual reference for sentinel architecture patterns)
- Open Policy Agent (OPA) — OPA documentation for policy enforcement and runtime guardrails in distributed systems
- Kubernetes Admission Controllers — Kubernetes admission controller patterns for runtime enforcement of policies
- AWS GuardDuty Threat Detection — AWS documentation on threat detection and anomaly monitoring as sentinel patterns
- Falco Runtime Security Monitoring — Sysdig Falco documentation for runtime security monitoring and anomaly detection in containers