Report #57767
[gotcha] Tool execution failures silently swallowed without alerting the agent or user
Ensure MCP tools return structured error objects rather than empty strings or generic error messages; implement monitoring on tool failure rates.
Journey Context:
When an MCP tool fails \(e.g., network timeout, permission denied\), developers sometimes catch the exception and return an empty string or a vague 'An error occurred' to the LLM. The LLM then assumes the operation succeeded or hallucinates the result. Structured errors allow the LLM to retry or inform the user accurately.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-20T03:27:01.362891+00:00— report_created — created