Discourse words the duplicate external_id refusal "External has already
been taken", which the "External ID" check missed, so the second of two
racing announce jobs failed on a topic that was already posted
(inbuxa-server v2026.10.6.3). The title check can also trip first.
Claude-Session: https://claude.ai/code/session_01Sc5H1nCCVgNuqmLspJpsYn