@zanii/minimization

Did you only take what you needed? GDPR Art. 5(1)(c) data minimization is unprovable today — you can only assert it. This makes it a proof: commit the declared minimum field set, then prove every field an agent accessed was inside it.

npm install @zanii/minimization @zanii/core

import { commitFieldSet, buildAccessProof, verifyMinimization } from '@zanii/minimization';

const { commitment } = commitFieldSet(['name', 'email', 'account_id']);   // the declared minimum
await zanii.record(buildAccessProof({ fieldSetCommitment: commitment, accessed: ['name', 'email'], ts: now }));

const r = verifyMinimization(proof, ['name', 'email', 'account_id']);
r.ok; r.excess;   // excess = fields accessed OUTSIDE the declared minimum — provable over-collection

Python: from zanii.minimization import commit_field_set, build_access_proof, verify_minimization — byte-identical field-set commitments across languages.

Why it can't be gamed after the fact

The declared minimum is committed (minfields:v1:…) and referenced on each access receipt. If the operator later tries to justify an over-collection by claiming the field was always declared, verifyMinimization catches it — the widened set doesn't match the committed commitment. Composes @zanii/redact field commitments + purpose-bound delegation.

The limit, stated up front

Proves declared-vs-accessed — that the agent stayed inside the minimum it declared. It does NOT prove the minimum was well-chosen (a judgement, not a fact), and it proves the recorded accesses only.