firecrawl-reliability-patterns by jeremylongshore

---
name: firecrawl-reliability-patterns
description: |
  Implement FireCrawl reliability patterns including circuit breakers, idempotency, and graceful degradation.
  Use when building fault-tolerant FireCrawl integrations, implementing retry strategies,
  or adding resilience to production FireCrawl services.
  Trigger with phrases like "firecrawl reliability", "firecrawl circuit breaker",
  "firecrawl idempotent", "firecrawl resilience", "firecrawl fallback", "firecrawl bulkhead".
allowed-tools: Read, Write, Edit
version: 1.0.0
license: MIT
author: Jeremy Longshore <[email protected]>
---

# FireCrawl Reliability Patterns

## Overview
Production-grade reliability patterns for FireCrawl integrations.

## Prerequisites
- Understanding of circuit breaker pattern
- opossum or similar library installed
- Queue infrastructure for DLQ
- Caching layer for fallbacks

## Circuit Breaker

```typescript
import CircuitBreaker from 'opossum';

const firecrawlBreaker = new CircuitBreaker(
  async (operation: () => Promise<any>) => operation(),
  {
    timeout: 30000,
    errorThresholdPercentage: 50,
    resetTimeout: 30000,
    volumeThreshold: 10,
  }
);

// Events
firecrawlBreaker.on('open', () => {
  console.warn('FireCrawl circuit OPEN - requests failing fast');
  alertOps('FireCrawl circuit breaker opened');
});

firecrawlBreaker.on('halfOpen', () => {
  console.info('FireCrawl circuit HALF-OPEN - testing recovery');
});

firecrawlBreaker.on('close', () => {
  console.info('FireCrawl circuit CLOSED - normal operation');
});

// Usage
async function safeFireCrawlCall<T>(fn: () => Promise<T>): Promise<T> {
  return firecrawlBreaker.fire(fn);
}
```

## Idempotency Keys

```typescript
import { v4 as uuidv4 } from 'uuid';
import crypto from 'crypto';

// Generate deterministic idempotency key from input
function generateIdempotencyKey(
  operation: string,
  params: Record<string, any>
): string {
  const data = JSON.stringify({ operation, params });
  return crypto.createHash('sha256').update(data).digest('hex');
}

// Or use random key with storage
class IdempotencyManager {
  private store: Map<string, { key: string; expiresAt: Date }> = new Map();

  getOrCreate(operationId: string): string {
    const existing = this.store.get(operationId);
    if (existing && existing.expiresAt > new Date()) {
      return existing.key;
    }

    const key = uuidv4();
    this.store.set(operationId, {
      key,
      expiresAt: new Date(Date.now() + 24 * 60 * 60 * 1000),
    });
    return key;
  }
}
```

## Bulkhead Pattern

```typescript
import PQueue from 'p-queue';

// Separate queues for different operations
const firecrawlQueues = {
  critical: new PQueue({ concurrency: 10 }),
  normal: new PQueue({ concurrency: 5 }),
  bulk: new PQueue({ concurrency: 2 }),
};

async function prioritizedFireCrawlCall<T>(
  priority: 'critical' | 'normal' | 'bulk',
  fn: () => Promise<T>
): Promise<T> {
  return firecrawlQueues[priority].add(fn);
}

// Usage
await prioritizedFireCrawlCall('critical', () =>
  firecrawlClient.processPayment(order)
);

await prioritizedFireCrawlCall('bulk', () =>
  firecrawlClient.syncCatalog(products)
);
```

## Timeout Hierarchy

```typescript
const TIMEOUT_CONFIG = {
  connect: 5000,      // Initial connection
  request: 30000,     // Standard requests
  upload: 120000,     // File uploads
  longPoll: 300000,   // Webhook long-polling
};

async function timedoutFireCrawlCall<T>(
  operation: 'connect' | 'request' | 'upload' | 'longPoll',
  fn: () => Promise<T>
): Promise<T> {
  const timeout = TIMEOUT_CONFIG[operation];

  return Promise.race([
    fn(),
    new Promise<never>((_, reject) =>
      setTimeout(() => reject(new Error(`FireCrawl ${operation} timeout`)), timeout)
    ),
  ]);
}
```

## Graceful Degradation

```typescript
interface FireCrawlFallback {
  enabled: boolean;
  data: any;
  staleness: 'fresh' | 'stale' | 'very_stale';
}

async function withFireCrawlFallback<T>(
  fn: () => Promise<T>,
  fallbackFn: () => Promise<T>
): Promise<{ data: T; fallback: boolean }> {
  try {
    const data = await fn();
    // Update cache for future fallback
    await updateFallbackCache(data);
    return { data, fallback: false };
  } catch (error) {
    console.warn('FireCrawl failed, using fallback:', error.message);
    const data = await fallbackFn();
    return { data, fallback: true };
  }
}
```

## Dead Letter Queue

```typescript
interface DeadLetterEntry {
  id: string;
  operation: string;
  payload: any;
  error: string;
  attempts: number;
  lastAttempt: Date;
}

class FireCrawlDeadLetterQueue {
  private queue: DeadLetterEntry[] = [];

  add(entry: Omit<DeadLetterEntry, 'id' | 'lastAttempt'>): void {
    this.queue.push({
      ...entry,
      id: uuidv4(),
      lastAttempt: new Date(),
    });
  }

  async processOne(): Promise<boolean> {
    const entry = this.queue.shift();
    if (!entry) return false;

    try {
      await firecrawlClient[entry.operation](entry.payload);
      console.log(`DLQ: Successfully reprocessed ${entry.id}`);
      return true;
    } catch (error) {
      entry.attempts++;
      entry.lastAttempt = new Date();

      if (entry.attempts < 5) {
        this.queue.push(entry);
      } else {
        console.error(`DLQ: Giving up on ${entry.id} after 5 attempts`);
        await alertOnPermanentFailure(entry);
      }
      return false;
    }
  }
}
```

## Health Check with Degraded State

```typescript
type HealthStatus = 'healthy' | 'degraded' | 'unhealthy';

async function firecrawlHealthCheck(): Promise<{
  status: HealthStatus;
  details: Record<string, any>;
}> {
  const checks = {
    api: await checkApiConnectivity(),
    circuitBreaker: firecrawlBreaker.stats(),
    dlqSize: deadLetterQueue.size(),
  };

  const status: HealthStatus =
    !checks.api.connected ? 'unhealthy' :
    checks.circuitBreaker.state === 'open' ? 'degraded' :
    checks.dlqSize > 100 ? 'degraded' :
    'healthy';

  return { status, details: checks };
}
```

## Instructions

### Step 1: Implement Circuit Breaker
Wrap FireCrawl calls with circuit breaker.

### Step 2: Add Idempotency Keys
Generate deterministic keys for operations.

### Step 3: Configure Bulkheads
Separate queues for different priorities.

### Step 4: Set Up Dead Letter Queue
Handle permanent failures gracefully.

## Output
- Circuit breaker protecting FireCrawl calls
- Idempotency preventing duplicates
- Bulkhead isolation implemented
- DLQ for failed operations

## Error Handling
| Issue | Cause | Solution |
|-------|-------|----------|
| Circuit stays open | Threshold too low | Adjust error percentage |
| Duplicate operations | Missing idempotency | Add idempotency key |
| Queue full | Rate too high | Increase concurrency |
| DLQ growing | Persistent failures | Investigate root cause |

## Examples

### Quick Circuit Check
```typescript
const state = firecrawlBreaker.stats().state;
console.log('FireCrawl circuit:', state);
```

## Resources
- [Circuit Breaker Pattern](https://martinfowler.com/bliki/CircuitBreaker.html)
- [Opossum Documentation](https://nodeshift.dev/opossum/)
- [FireCrawl Reliability Guide](https://docs.firecrawl.com/reliability)

## Next Steps
For policy enforcement, see `firecrawl-policy-guardrails`.