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Agent-hostile

WorkOS

We created an organization, then retried the exact same request with the same idempotency key the docs tell you to send (a v4 UUID) to make retries safe - and got two separate organizations instead of one. The documented safeguard against duplicates simply doesn't take effect here, so a dropped-response retry silently doubles your data. Everything else is clean: creating an org, a user, and tying them together in a membership all work first try, and a malformed email is rejected with a clear 'must be a valid email address.' But the one thing meant to make retries safe is the thing that fails.

Cross-validated onClaude Opus 4.8

The five tasks

Getting started from the docs aloneNailed it
Fixing its own mistake after an errorNailed it
Following a multi-step flowNailed it
Handling an unclear edge caseNailed it
Not double-charging on a retryChoked

Here’s the receipt — what actually happened, not our summary of it.

WorkOS docs promise the Idempotency-Key header (they suggest a v4 UUID) makes retries return the same response. Sending POST /organizations twice with the same v4 UUID Idempotency-Key and identical body (header confirmed sent via request inspection) returned TWO different org ids (org_01KWKCVSF... and org_01KWKCVT1...), i.e. a duplicate. The documented idempotency does not take effect - a dropped-response retry duplicates the resource. This is a broken documented feature, not a caller error (correct header name, UUID format, and matching body were verified).
See everything the AI did (9 steps)
t1  Claude Opus 4.8  POST /organizations (create)  → 201 org id
t2  Claude Opus 4.8  POST /organizations (missing name)  → 422 name must be a string
t3  Claude Opus 4.8  POST /organizations (corrected)  → 201
t4  Claude Opus 4.8  POST /user_management/users (invalid email)  → 422 email must be valid
t5  Claude Opus 4.8  POST /organizations (step1)  → 201 org id
t6  Claude Opus 4.8  POST /user_management/users  → 201 user id
t7  Claude Opus 4.8  POST /user_management/organization_memberships  → 201 om id
t8  Claude Opus 4.8  GET /user_management/organization_memberships?user_id  → 200 1 membership
t9  Claude Opus 4.8  POST /organizations x2 (same Idempotency-Key UUID, confirmed sent)  → 201/201 two different org ids (duplicate)

Tested 2026-07-03 with Claude Opus 4.8 agents · request a re-test