received unknown parameter: agent_facts_unknown

Stripe API · POST /v1/customers · HTTP 400 parameter_unknown

Status: ✅ verified:server:sandbox · first seen 2026-10-24 · last confirmed 2026-10-26 · 10 confirmations from 2 vantages

A 400 for a parameter that fails validation, such as parameter_unknown, is not saved under its Idempotency-Key: a retry with the same key is executed again and has no Idempotent-Replayed header.

What to do

1. No client-side fix known (by design).

Dimensions

env: sandbox · plan: any · region: any · account_state: any

Evidence

Probe af:stripe:probe:validation-error-not-replayed (declarative, source)

Observations: none from reporters yet.

Machine access

curl -s https://apifacts.dev/v0/check \
  -H 'content-type: application/json' \
  -d '{"target":{"method":"POST","url":"https://api.stripe.com/v1/customers"},"error":{"status":400,"body_excerpt":"received unknown parameter: agent_facts_unknown"}}'

YAML: facts/stripe/validation-errors-are-not-replayed.yaml

Data: CC BY 4.0 · apifacts registry · This page is generated; edit the YAML, not the page.