Behavioral Attestation

Chainabit's attestation system produces cryptographic proof of effort at every layer of the execution model. This page explains how the proof trail works — from individual bit completions to verifiable credentials that third parties can independently validate.

The Proof Trail

Every action on Chainabit produces a link in the proof chain:

Bit Completion → Completion Event (hash-linked) → Period Evaluation → Period Signature (SHA256) → Certificate (W3C VC)

1. Hash-Linked Execution Events

When a Bit is completed, a bit_completion_event is recorded with:

• A previous_event_hash referencing the prior event in the chain
• A verification_level indicating the trust tier of the evidence
• Optional evidence_url and evidence_metadata for artifact-backed completions

The previous_event_hash creates an immutable, tamper-evident sequence — like a blockchain of behavioral events. Altering any event invalidates all subsequent hashes.

2. Verification Levels

Each completion carries a verification level — a trust gradient from self-reported to cryptographic:

Level	Trust	Source
self_attested	Lowest	User clicked checkbox
note_provided	Low	User added descriptive note
artifact_backed	Medium	Evidence file/URL uploaded
peer_validated	Medium	Validated by accountability buddy
ai_verified	High	AI reviewed and scored above threshold
external_source	High	CI/CD, API call, system integration
cryptographic	Highest	IDE git commit hash, externally signed

Chains define a required_verification_level. Only completions meeting or exceeding this level count toward period evaluation. A chain requiring ai_verified won't count a self_attested checkbox.

3. Period Attestation Signatures

When a chain period's requirements are met (e.g., 5 of 7 days completed), a period signature is created:

• signature_hash = SHA256(chain_id : period_id : completed_count : required_count : signed_at : source)
• source indicates who attested: user, ai, or system
• AI can co-attest with an ai_role and ai_attestation_data containing verification scores

The signature is the core attestation unit — it proves that a specific number of verified executions occurred within a defined time window.

4. Milestone Certificates

When chains reach achievement thresholds, the system issues certificates:

Streak milestones: 7, 30, 90, 180, 365 consecutive attested periods Completion milestones: 10, 50, 100, 500, 1000 total verified completions Consistency milestones: 80%+ period completion rate sustained over 30+ days

Certificates are:

• Polymorphic — issued for chains, bits, chain periods, races, seasons, or custom achievements
• NFT-mintable — can be minted on-chain via the is_minted + mint_tx_hash fields
• W3C VC-exportable — exportable as standards-compliant Verifiable Credentials 2.0

5. W3C Verifiable Credentials

Certificates can be exported as W3C Verifiable Credentials 2.0:

{
  "@context": [
    "https://www.w3.org/2018/credentials/v1",
    "https://chainabit.com/credentials/v1"
  ],
  "type": ["VerifiableCredential", "BehavioralExecutionCredential"],
  "issuer": "https://chainabit.com",
  "credentialSubject": {
    "achievement": "streak_90",
    "chainId": "...",
    "attestedPeriods": 90,
    "consistencyRate": 0.95
  },
  "proof": {
    "type": "SHA256Hash",
    "certificateHash": "a1b2c3..."
  }
}

Public Verification

Three endpoints allow anyone to verify attestations without authentication:

Endpoint	Returns
GET /public/verify/signatures/:hash	Attestation metadata: chain info, period dates, counts, source
GET /public/verify/certificates/:hash	Certificate details + W3C VC payload + NFT status
GET /public/verify/chains/:id/summary	Public chain summary (only if is_visible=true)

These endpoints never expose personally identifiable information. They return only the attestation metadata needed for independent verification.

AI Co-Attestation

AI participates in the attestation layer at multiple levels:

• Period co-attestation — AI can attest chain periods alongside user attestation, adding an ai_verification_score and structured ai_attestation_data
• Adaptive directives — AI generates recommendations (schedule adjustments, difficulty changes, bit decomposition) stored as chain_ai_directives
• Certificate evaluation — AI can evaluate milestone readiness and trigger certificate issuance

AI attestation creates a dual-signature model: human intent + AI verification, producing higher-confidence behavioral proof.