{
  "schema_version": "lvl-knowledge-lesson-v1",
  "id": "path-ma-03-rate-limits-and-cost",
  "category": "path",
  "path_ids": [
    "deploy-multi-agent-workflow"
  ],
  "title": "Rate limits and cost classes",
  "summary": "Aggressive retries turn one flaky tool into a bill. Class tools by cost and cap them.",
  "body": "## Cost classes (example)\n\n| Class | Examples | Retry policy |\n|-------|----------|--------------|\n| Cheap | local parse | aggressive |\n| Medium | search API | bounded |\n| Expensive | LLM + paid unlock | strict |\n\n## Circuit open\n\nWhen 429s cluster, stop spawning siblings. Shared limiters beat per-agent free-for-alls.\n\n## Takeaway\n\nThrottle is a safety feature, not optional polish.",
  "concepts": [
    "rate-limit",
    "cost-class",
    "circuit-breaker"
  ],
  "related_skills_optional": [
    {
      "skill_id": "tool-call-rate-limiter",
      "name": "Tool-Call Rate Limiter",
      "price_usd": 3.99,
      "price_label": "$3.99 / unlock",
      "summary": "Per-tool throttles and backoff so agents stop hammering paid APIs.",
      "outline": "https://lvlltd.com/skills/tool-call-rate-limiter/outline.json",
      "challenge": "https://lvlltd.com/api/pay?skill=tool-call-rate-limiter",
      "listing": "https://lvlltd.com/listings/tool-call-rate-limiter/",
      "available": true,
      "optional": true,
      "label": "optional_implementation"
    },
    {
      "skill_id": "agent-budget-governor",
      "name": "Agent Budget Governor",
      "price_usd": 4.99,
      "price_label": "$4.99 / unlock",
      "summary": "Hard spend caps and per-run budgets for agent tool use — stop rules before runaway cost.",
      "outline": "https://lvlltd.com/skills/agent-budget-governor/outline.json",
      "challenge": "https://lvlltd.com/api/pay?skill=agent-budget-governor",
      "listing": "https://lvlltd.com/listings/agent-budget-governor/",
      "available": true,
      "optional": true,
      "label": "optional_implementation"
    }
  ],
  "sort_order": 30,
  "estimated_minutes": 8,
  "last_updated": "2026-07-22T12:00:00.000Z",
  "freshness": {
    "last_updated_at": "2026-07-22T12:00:00.000Z",
    "days_since_update": 0,
    "band": "fresh",
    "score_0_100": 95,
    "label": "Fresh",
    "display": "Fresh · updated 2026-07-22 (0d ago)"
  },
  "integrity": {
    "knowledge_free": true,
    "skills_optional": true,
    "note": "This lesson is complete without purchasing any skill."
  },
  "related_bundles_optional": [],
  "url": "https://lvlltd.com/learn/lessons/path-ma-03-rate-limits-and-cost/",
  "updated_at": "2026-07-22T21:10:40.587Z"
}