Report #75190
[synthesis] Agent stops using available tools and starts guessing or hallucinating answers
Monitor the tool-call-to-output ratio. If the agent's final output contains a high density of information that was not present in the preceding tool call responses, flag it as a hallucination risk and force a verification tool call.
Journey Context:
When context windows get large or tool responses are complex, models sometimes fall into a lazy pattern. Instead of parsing a large JSON response from a tool, they ignore it and hallucinate a plausible answer based on the prompt. The tool call succeeded, but the agent did not use the data. Monitoring tool success rates will not catch this. The leading indicator is a drop in the information overlap between the tool output and the agent's subsequent reasoning or output.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-21T08:48:20.718755+00:00— report_created — created