Definition
A token bucket admits work by consuming tokens from a bounded pool that refills at a configured rate. Bucket capacity determines the accumulated burst allowance; refill rate governs sustained admission. The policy must define its scope and token cost per operation.
Why It Matters
- A catalog refresh and many shopper assistants can share a destination API quota. Uncoordinated callers can overload that allowance.
- Within a Commerce Intelligence OS, request admission should preserve the urgency and completion state of each customer task.
How It Works
- Identify the actual quota scope, such as merchant, credential, endpoint, or shared account. Count every caller using that allowance.
- Set capacity, refill rate, and per-request token cost. Coordinate token consumption atomically where workers share a limit; giving every worker a full independent bucket can multiply traffic.
- When tokens are unavailable, defer within a bounded deadline or return a clear throttled state. Respect destination guidance and retain the original operation identity for retried writes.
- Monitor admitted and deferred traffic alongside queue age. Rate limiting does not bound concurrent slow requests, so evaluate a separate concurrency limit where needed.
Ecommerce Example
Context: Illustrative example: an idealized shared bucket starts with 20 tokens, refills at five per second, and charges one token per stock lookup.
Recommended move: It can admit a burst of 20 immediate lookups and then sustain five per second after depletion, assuming the destination supports that policy.
Why it matters: These hypothetical settings explain admission behavior; they are not an iKawn capacity promise or a provider quota recommendation.
iKawn Framework
Scope
The iKawn framework connects agent tasks with shared service allowances.
Budget
Assign explicit burst and sustained admission limits.
Defer
Preserve task deadlines and truthful pending states.
Measure
Review delayed customer work as well as request counts.
Concise Summary
Token buckets separate burst allowance from sustained request rate. Coordinate shared callers and handle deferred work explicitly.