Slack Web API 429 ratelimited on chat.postMessage: strict Retry-After versus exponential backoff with jitter
Slack Web API throttling surfaces as HTTP 429 Too Many Requests with a JSON body whose error field is "ratelimited". The limit applies per method and per app/workspace/token context, so a client can remain healthy on one endpoint while another such as chat.postMessage begins returning 429. Slack does not publish exact per-method budgets or burst allowances,
slack