Evidence case

A bounded evidence case another party can inspect.

An evidence case packages selected signed records, preserved native artifacts, and verification results so a separate recipient can inspect the same material without access to the source systems.

This summary illustrates how findings may be presented. It is not a signed evidence bundle and cannot itself be cryptographically verified.

MCP tool callGateway decisionPayment artifactMissing evidence
The scenario

A customer disputes a paid MCP tool call to a market-data service.

This scenario is illustrative. It intentionally includes missing evidence: a complete happy-path example would misrepresent what a real evidence case looks like.

  1. 14:08:09authorization reference supplied
  2. 14:08:10gateway reports allow
  3. 14:08:11MCP server reports tools.call market_search
  4. 14:08:12payment provider reports authorized
  5. 14:08:13tool server reports result digest
  6. not recordeddelivery observation: not supplied
  7. not recordedcounterparty acknowledgment: not supplied
Findings
Established
  • the supplied keys validate the gateway and tool-server signatures;
  • the tool name and argument digest are bound by the tool-server record;
  • the payment-provider artifact is linked to the case;
  • the result artifact supplied for review matches its bound digest.
Missing
  • independent delivery observation;
  • recipient acknowledgment;
  • evidence that every relevant retry was included.
Not evaluated
  • commercial liability;
  • legal sufficiency;
  • correctness of the underlying service result;
  • whether the issuer omitted another event.
What verification checks
What verification establishes

Verification checks the record's structure, signature, issuer information, and bound digests against the supplied verification material.

What verification does not establish

Verification does not independently prove that every relevant real-world event was captured, that the issuer's statements were truthful, or that an underlying system correctly enforced its policy.

An evidence case is a product artifact. It is not a new PEAC wire type.