Field	Description
`allowed`	Can customer proceed
`balance`	Units remaining
`included_usage`	Total usage included in plan
`unlimited`	No limit enforced

Feature Types

Type	Behavior
`boolean`	Access granted or denied
`metered`	Usage tracked against limit
`credit_system`	Pool for multiple features

Security Model

Layer	Purpose	Trust
Frontend	UX (show/hide UI)	Untrusted
Backend	Enforcement	Required

Backend Implementation

import { Autumn } from "autumn-js";

const autumn = new Autumn({ secretKey: process.env.AUTUMN_SECRET_KEY });

// 1. Check
const { data } = await autumn.check({ customer_id, feature_id: "api_calls" });
if (!data.allowed) return { error: "Limit reached" };

// 2. Work
const result = await doWork();

// 3. Track
await autumn.track({ customer_id, feature_id: "api_calls", value: 1 });
return result;

from autumn import Autumn

autumn = Autumn('am_sk_test_xxx')

response = await autumn.check(customer_id="user_123", feature_id="api_calls")
if not response.allowed:
    raise HTTPException(403, "Limit reached")

result = await do_work()
await autumn.track(customer_id="user_123", feature_id="api_calls", value=1)

React Implementation

import { useCustomer } from "autumn-js/react";

const { check, refetch } = useCustomer();

const handleAction = async () => {
  const { data } = await check({ featureId: "messages" });
  if (!data?.allowed) {
    showUpgradePrompt();
    return;
  }
  
  await performAction();
  await refetch();
};

Displaying Usage

const { customer } = useCustomer();
const feature = customer?.features?.api_calls;

<p>{feature?.balance} / {feature?.included_usage}</p>

Credit Systems

Track the underlying metered feature, not the credit system:

// Config: credits → api_calls (1), image_gen (10)

// Wrong
await autumn.track({ customer_id, feature_id: "credits", value: 10 });

// Right - Autumn deducts 10 credits automatically
await autumn.track({ customer_id, feature_id: "image_gen", value: 1 });

Common Gotchas

Track after success - Only track if work completes successfully
Backend required - Frontend checks can be bypassed
Credit systems - Track metered features, not the credit pool
Idempotency - Use idempotency_key to prevent double-counting
Batch tracking - Pass higher value for bulk operations

Feature Types

Security Model

Backend Implementation

React Implementation

Displaying Usage

Credit Systems

Common Gotchas

Resources

autumn-add-usage-tracking

Autumn Usage Tracking

Quick Reference

Core Pattern

Check Response

More from useautumn/skills

autumn-best-practices

autumn-add-payments

autumn-create-customer