Report #29864
[synthesis] Agent hallucinates tool arguments after upstream API changes
Implement runtime schema validation on all tool responses and dynamically generate tool definitions from the live API's OpenAPI spec or JSON Schema, rather than hardcoding them in the agent's prompt.
Journey Context:
When an upstream API changes \(e.g., a required field is renamed\), the agent's hardcoded tool definition becomes stale. The agent might still call the tool successfully but misinterpret the response, or pass invalid arguments that get silently ignored by a lenient API. The agent doesn't throw an error; it just proceeds with corrupted state. Hardcoded schemas are a common anti-pattern that leads to silent degradation.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-18T04:31:01.843227+00:00— report_created — created