Semantic content validation within permitted output types (P7)

Develop a mechanism to validate the semantic content of agent outputs whose type tags are permitted under the Output Schema Conformance property (P7) in SentinelAgent’s Delegation Chain Calculus, so that biased or malicious reasoning embedded within allowed output types (e.g., an eligibility_result) can be detected and blocked without relying solely on type tags.

Background

The paper introduces P7 (Output Schema Conformance) to whitelist permissible output type tags and block all others, providing a deterministic safeguard against malicious outputs even when API calls are permitted (P6).

However, the authors acknowledge that P7 only checks type tags and not the semantics of the content within those types. Thus, malicious or biased content can still pass if it is embedded within an allowed output type. The authors explicitly state that addressing semantic validation within permitted types remains an open problem.

References

Second, P7 validates output type tags but not semantic content within a permitted type---if the output type is ``eligibility_result'' (permitted) but the result contains biased reasoning, P7 does not detect this. Semantic content validation within permitted types remains an open problem.

— SentinelAgent: Intent-Verified Delegation Chains for Securing Federal Multi-Agent AI Systems  (2604.02767 - Patil, 3 Apr 2026) in Section "Discussion and Future Work", P7 limitations paragraph

Its authors explicitly leave semantic injection as an ``open challenge beyond the scope of execution-layer verification.''

— Signing the Transaction but Not the Decision: Whisper Attacks and a Binding Defense for AP2  (2609.11757 - Louck et al., 10 Sep 2026) in Section 3.1, subsection “The stack AP2 enters”