grammarly-cost-tuning

# Grammarly Cost Tuning

## Overview

Grammarly enterprise pricing is per-seat with API costs driven by text check request volume and document length. Each grammar check, tone analysis, and plagiarism scan consumes API quota proportional to word count. For organizations processing thousands of documents daily, unchecked API usage — especially on long documents or duplicate content — creates substantial cost overrun. Implementing validation gates, result caching, and sample-based scoring reduces API spend by 40-60% without sacrificing quality coverage.

## Cost Breakdown

| Component | Cost Driver | Optimization |
|-----------|------------|--------------|
| Seat licenses | Per-user/month enterprise pricing | Audit active seats quarterly; remove inactive users |
| Text check requests | Per-call API quota on grammar/tone checks | Cache results for identical text; deduplicate requests |
| Document length | API cost scales with word count per request | Chunk documents over 10K words; skip boilerplate sections |
| Plagiarism scans | Higher-cost endpoint for originality checks | Run only on final drafts, not every revision |
| AI rewrite suggestions | Premium feature with per-request cost | Batch rewrites; limit to flagged passages only |

## API Call Reduction

```typescript
class GrammarlyCostGate {
  private resultCache = new Map<string, any>();

  shouldCheck(text: string): boolean {
    const words = text.split(/\s+/).length;
    return words >= 30 && words <= 50_000; // Skip too-short; chunk too-long
  }

  async checkWithCache(text: string, checkFn: (t: string) => Promise<any>): Promise<any> {
    const hash = this.hashText(text);
    if (this.resultCache.has(hash)) return this.resultCache.get(hash);
    const result = await checkFn(text);
    this.resultCache.set(hash, result);
    return result;
  }

  sampleDocuments(documents: string[], rate = 0.2): string[] {
    // For bulk content audits, score a representative sample
    return documents.filter(() => Math.random() < rate);
  }

  private hashText(text: string): string {
    return text.slice(0, 200) + '|' + text.length;
  }
}
```

## Usage Monitoring

```typescript
class GrammarlyUsageMonitor {
  private daily = { score: 0, ai: 0, plagiarism: 0 };
  private budgets = { score: 5000, ai: 1000, plagiarism: 200 };

  record(type: 'score' | 'ai' | 'plagiarism'): void {
    this.daily[type]++;
    const utilization = (this.daily[type] / this.budgets[type]) * 100;
    if (utilization > 80) {
      console.warn(`Grammarly ${type} budget ${utilization.toFixed(0)}% used: ${this.daily[type]}/${this.budgets[type]}`);
    }
  }

  getReport(): Record<string, { used: number; budget: number }> {
    return Object.fromEntries(
      Object.keys(this.daily).map(k => [k, {
        used: this.daily[k as keyof typeof this.daily],
        budget: this.budgets[k as keyof typeof this.budgets]
      }])
    );
  }
}
```

## Cost Optimization Checklist

- [ ] Cache grammar check results for identical text
- [ ] Validate text length before sending (30-50K word range)
- [ ] Use sample-based scoring for bulk content audits (20% sample)
- [ ] Run plagiarism checks only on final drafts
- [ ] Chunk documents over 10K words into smaller segments
- [ ] Skip boilerplate sections (headers, footers, legal text)
- [ ] Limit AI rewrite suggestions to flagged passages only
- [ ] Set per-endpoint daily budget alerts at 80% threshold

## Error Handling

| Issue | Cause | Fix |
|-------|-------|-----|
| API quota exhausted mid-day | No usage monitoring or budget gates | Implement daily budget tracking with early warning |
| Duplicate checks on same content | No result caching | Hash-based cache for identical text submissions |
| Timeout on large documents | Single 50K+ word submission | Chunk into 10K-word segments and process sequentially |
| Plagiarism costs spiking | Running originality check on every save | Restrict to final draft submissions only |
| Stale cache returning outdated scores | Algorithm updates not reflected | TTL of 7 days on cached results; invalidate on version change |

## Resources

- [Grammarly Enterprise](https://www.grammarly.com/business)
- [Grammarly Developer API](https://developer.grammarly.com)

## Next Steps

See `grammarly-performance-tuning`.