Report #91707
[architecture] Schema drift and field injection between agent boundaries due to permissive validation
Enforce 'closed world' JSON Schema Draft 2020-12 with 'additionalProperties: false' and 'unevaluatedProperties: false'; version schemas via content hash in the 'X-Schema-Hash' header and reject messages that fail strict validation.
Journey Context:
Loose schemas allow upstream agents to add 'helpful' fields that downstream agents misinterpret \(e.g., a 'confidence' field overriding internal calculations\). The 'unevaluatedProperties' keyword is crucial for compositions \(allOf/anyOf\) to prevent leakage. Hashing the schema itself prevents version skew where agents run different schema interpretations. Tradeoff: Breaks forward compatibility; you must version and migrate explicitly, but this is safer than silent failures.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-22T12:31:14.572489+00:00— report_created — created