[drk-ram]

What

Validate message_or_request and metadata mapping types and reject empty string parent_record_hash in a2a_adapter, bound metadata_from_sdk_message float-to-int conversion by RFC 8785 safe-integer limits (2**53 - 1), and reject duplicate JSON keys and NaN/Infinity in hardware_acceptance.

Why

Closes #286.

Security impact

Prevents unhandled AttributeError/TypeError on malformed A2A envelopes, prevents lossy IEEE-754 floats >= 2**53 in protobuf Struct metadata from being coerced into imprecise integers, and closes duplicate-key JSON smuggling in the hardware acceptance harness.

Test plan

• pytest passes (pytest tests/unit/test_hardware_acceptance.py tests/unit/test_a2a_adapter.py -q: 27 passed, 1 skipped)
• ruff check passes (ruff check src tests/unit/test_hardware_acceptance.py: All checks passed!)
• mypy passes
• Manual test performed

DCO sign-off

• I certify that I wrote or have the right to submit this contribution, and I agree to the
  Developer Certificate of Origin (https://developercertificate.org).

[github-actions]

🟡 Contributor Check: MEDIUM

Check	Result
Profile	MEDIUM
Credential	LOW
Overall	MEDIUM

Automated check by AgenTrust Contributor Check.

[carloshvp]

Reviewed exact head 9e81cc380152ff2b2f01e35e5df706cb3fa58c0a in an isolated checkout.

The adapter refuses non-object metadata and empty supplied parent hashes, SDK float conversion is bounded to finite safe integers, and the hardware harness rejects ambiguous configuration/chain JSON before provider work. The focused adapter boundary control passes here and fails against the baseline adapter module. Valid adapter and harness software controls remain passing; this review does not claim hardware acceptance.

Independent validation in a fresh repository-hash-locked Python 3.12.10 environment: 780 tests passed, 16 skipped; pip check, configured Ruff, mypy, Bandit and diff whitespace checks passed. Commit sign-offs are present. Hosted CI and applicable independent maintainer/security gates remain separate prerequisites to merge.

Reviewed with OpenAI Codex.

[carloshvp]

Reviewed current head 2a0c45e478818b899285b2eab9f1faad05d46cba in an isolated checkout.

The adapter rejects non-object metadata and empty parent hashes, SDK integer normalization is limited to finite safe-integer values, and the hardware-harness JSON loader rejects duplicate members. This is software input/transport validation; I did not run a hardware acceptance session.

Fresh Python 3.12.10 validation: 836 passed, 16 skipped; Ruff, mypy and configured Bandit pass. The installed dependencies are consistent, and the PR commit carries a DCO sign-off. The required format check and whitespace check pass. Hosted CI and the required independent security approvals remain separate.

Reviewed with OpenAI Codex.