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Evidence Provenance in VB-OS

Provenance answers the question: where did this evidence come from?

VB-OS does not verify that evidence is true: it verifies that evidence came from the declared source. This is a fundamental scope distinction. The boundary confirms the origin, not the accuracy.

Declaring Provenance Requirements

Section titled “Declaring Provenance Requirements”

Boundaries specify provenance requirements using require_provenance:

require_provenance: risk_score: internal_risk_engine
require_provenance: kyc_status: identity_provider
require_provenance: account_balance: core_banking_system

This declares that:

  • risk_score must come from a source identified as internal_risk_engine
  • kyc_status must come from a source identified as identity_provider
  • account_balance must come from a source identified as core_banking_system

How Provenance Is Tracked

Section titled “How Provenance Is Tracked”

When evidence is acquired through a connector, the connector attaches provenance metadata to each field. This metadata records:

  • The acquisition_class: the classification of how evidence was acquired
  • The connector_id: which connector instance acquired the evidence
  • The acquired_at: the timestamp when evidence was acquired

When evidence is submitted directly via the API (not through a connector), it has no provenance metadata. If the boundary requires provenance for a directly-submitted field, the evaluation will fail.

Provenance vs. Truth

Section titled “Provenance vs. Truth”

This distinction is critical to understanding VB-OS’s scope:

Concern VB-OS’s Role
“Did this risk score come from our internal risk engine?” Yes. Provenance verification
“Is this risk score correct?” No. Truth is the source system’s responsibility
“Was the KYC check performed by our identity provider?” Yes. Provenance verification
“Is this person actually who they claim to be?” No. Truth is the identity provider’s responsibility

VB-OS provides a verifiable chain from source to evaluation. It does not duplicate the source system’s validation logic.

Provenance in the Evaluation Record

Section titled “Provenance in the Evaluation Record”

Provenance metadata is preserved in the immutable evaluation record. When an evaluation is replayed, the provenance of the evaluation is part of the replayed evidence: auditors can verify not just what the evidence values were, but where they came from.

Next Steps

Section titled “Next Steps”