SymptomThe Bot clicks, a spinner appears, and then nothing exists anywhere: no output in the target application, no toast, no error, no credit charge message. The run looks like it succeeded.
CauseThe cloud browser trips anti-bot defences; after human takeover and handback the underlying action fails without surfacing an error to the agent or the operator.
DetectionCompare the target system's own record against the Bot's report. There is no in-product signal; the Bot reports calmly either way.
FixRequire every routine to emit a reviewable artifact naming what it produced and where, and give an empty result its own named outcome rather than treating it as success. Prefer an official API over the browser wherever one exists. Vendor named three fixes in flight on 2026-08-12 (cleaner takeover detection, less bot-flagged fingerprinting, proper error surfacing); no source through 2026-09-02 reports them shipped.