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Blueprint: SaaS Quota Watchdog

Protecting Specialized API Budgets from Autonomous Agent Loops​

Agents using expensive SaaS APIs (e.g., Clearbit, Apollo, specialized research tools) can exhaust a month's worth of credits in a single recursive loop. Governance must enforce daily and monthly tool-call quotas.

This blueprint demonstrates Tool-Level Rate Limiting and Quota Enforcement.

Architecture​

1. Master Policy Definition​

{
  "name": "saas-economic-policy",
  "priority": 8000,
  "rules": [
    {
      "id": "limit-saas-lookups",
      "effect": "allow",
      "principals": ["*"],
      "actions": ["saas:lookup"],
      "resources": ["*"]
    }
  ],
  "cost_policy": {
    "max_requests_per_day": 100
  }
}

2. Implementation​

Python Prototype​

from openai import OpenAI
import time

client = OpenAI(
    api_key="ignored",
    base_url="http://cz-gateway:8001/v1",
    default_headers={"X-ControlZero-User-ID": "marketing-bot"}
)

def perform_bulk_research(targets: list):
    for target in targets:
        try:
            # Control Zero Gateway tracks request count per project/user
            response = client.chat.completions.create(
                model="gpt-4o-mini",
                messages=[{"role": "user", "content": f"Lookup info for {target}"}],
                tools=[{"type": "function", "function": {"name": "saas:lookup", "parameters": {"type": "object"}}}]
            )
            print(f"Success for {target}")
        except Exception as e:
            if "quota exceeded" in str(e).lower():
                print(f"CRITICAL: Daily budget reached. Stopping loop.")
                break
            print(f"Error: {e}")

# Scenario: Attempting to process more than the daily quota
bulk_list = [f"company-{i}" for i in range(200)]
perform_bulk_research(bulk_list)

3. Validation Checklist​

  • Counter Persistence: Verify that the daily request counter correctly persists across container restarts (Redis check).
  • Reset Cycle: Ensure quotas reset at 00:00 UTC (or configured timezone).
  • Multi-User Quotas: Verify that User A hitting their quota does not block User B (if using user-level partitioning). 埋