dsh-output-custody-proof

In the DSH framework, tool results pass through multiple stages — model-visible projection, spill storage, telemetry export — yet verifying whether each handoff is intact, whether truncation or mixing occurred, often lacks an offline, deterministic audit trail. dsh-output-custody-proof fills that gap: it never reads result bodies or opens spill artifacts, and instead reconciles SHA-256 digests, byte counts, projection classifications, and stage markers recorded in the receipt to validate the full chain from source to projection, from budget to omission.

Core checks cover byte budgets and exact omission accounting, spill and source identity consistency, surface mapping correctness, stage ordering, duplicate call and locator identity, and explicitly disclosed upstream incompleteness. The schema accepts only bounded identifiers, byte counts, classification labels, and digests — never raw tool values, prompts, credentials, or spill locators — eliminating sensitive data ingress at the interface level.

This plugin is best suited for developers and security auditors working with DSH 0.1.1-rc.1 or later, especially those handling mixed or image results, Code Mode sub-calls, and upstream truncation paths. If you need a deterministic verdict on a custody receipt without opening a single spill file or touching a result body, this plugin provides a lightweight, zero-side-effect verification tool.