# Fortify

Use when the workflow lacks error handling, has been failing in production, or needs...

- Repository: https://github.com/sharpdeveye/maestro (592 stars)
- Category: Engineering
- License: MIT
- Last updated: 2026-04-29
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add sharpdeveye/maestro --skill fortify -g -a claude-code -y`
Codex: `npx skills add sharpdeveye/maestro --skill fortify -g -a codex -y`
Cursor: `npx skills add sharpdeveye/maestro --skill fortify -g -a cursor -y`
Gemini CLI: `npx skills add sharpdeveye/maestro --skill fortify -g -a gemini-cli -y`

## Description

Use when the workflow lacks error handling, has been failing in production, or needs retry logic, fallback strategies, and circuit breakers.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

## MANDATORY PREPARATION

Invoke /agent-workflow, it contains workflow principles, anti-patterns, and the **Context Gathering Protocol**. Follow the protocol before proceeding, if no workflow context exists yet, you MUST run /teach-maestro first.
Consult the guardrails-safety reference in the agent-workflow skill for defense-in-depth patterns and error boundary design.

---

Make the workflow resilient. Every external call will fail eventually, model APIs, tools, databases, third-party services. Fortify ensures the workflow handles failure gracefully.

### Fortification Layers

**Layer 1: Input Validation**

- Validate all inputs before processing
- Return clear error messages for invalid input
- Set size limits on all input fields

**Layer 2: Retry with Backoff**
For transient failures (network errors, rate limits, timeouts):

```yaml
Retry strategy:
  max_retries: 3
  initial_delay: 1s
  backoff_multiplier: 2
  max_delay: 30s
  retryable_errors: [429, 500, 502, 503, 504, TIMEOUT, CONNECTION_ERROR]
  non_retryable_errors: [400, 401, 403, 404]
```

**Layer 3: Fallback Responses**
When retries are exhausted:

- Use a cached previous response (if applicable)
- Use a simpler/cheaper model as fallback
- Return a graceful degradation response
- Escalate to human review

**Layer 4: Circuit Breakers**
When a service is consistently failing:

```yaml
Circuit breaker:
  failure_threshold: 5 consecutive failures
  state: CLOSED → OPEN (after threshold) → HALF_OPEN (after cooldown)
  cooldown: 60 seconds
  half_open_max_requests: 1
```

**Layer 5: Timeout Controls**
Every external call needs a timeout:

- Model API calls: 30-120s depending on task
- Tool executions: 10-60s depending on tool
- Database queries: 5-15s
- Third-party APIs: 10-30s

### Fortification Audit

For each component, verify:

The rest: https://github.com/sharpdeveye/maestro/blob/HEAD/source/skills/fortify/SKILL.md