ERC-8004 Validation

Cred Protocol runs an independent ERC-8004 validator at https://validator.credprotocol.com. Given an agent’s wallet, it computes a 0–100 composite trust score from three on-chain signals, pins the evidence to IPFS, and (optionally) submits the assessment on-chain to the ERC-8004 Reputation Registry on Base. This page is the methodology reference linked from the validator’s agent card.

Methodology version 1.0. Deployed on Base Mainnet (chain 8453); testable on Sepolia (11155111). Validator wallet: 0xc38947DA1EB4466D17d5C6c34a0f26Dbe803d107.

Composite score

Signal	Weight	Source	Normalisation
Credit	40%	Cred Score (300–1000) from `/api/v2/score`	Linear to 0–100
Sybil resistance	30%	Sybil score (0–100) from `/api/v2/identity/.../sybil`	Inverted — lower sybil risk contributes more
Identity	30%	Count of verified attestations (ENS, Gitcoin Passport, POAPs, …) from `/api/v2/identity/.../attestations`	Capped and scaled to 0–100

composite_score = 0.40·credit + 0.30·sybil + 0.30·identity, rounded to an integer. If a signal is unavailable its weight is redistributed and the result is marked lower-confidence.

Trust levels

`trust_level`	`composite_score`
`untrusted`	0–24
`low`	25–49
`moderate`	50–74
`high`	75–100

An agent with composite_score ≥ 50 is reported as verified: true.

Confidence

`confidence`	Meaning
`full`	All 3 signals available
`partial`	1–2 signals available
`minimal`	No signals available

Pipeline

Fetch signals — credit score, sybil score and identity attestations for the wallet (from the Cred Protocol API).
Score — weighted composite as above.
Pin evidence — the full breakdown, raw signal values, model versions and timestamp are pinned to IPFS (Pinata); the CID is returned as evidence_cid.
Submit on-chain (optional) — giveFeedback on the ERC-8004 Reputation Registry (and the Validation Registry where deployed) with the composite score and evidence URI. tx_hash / tx_status (pending → submitted → confirmed | failed) track it.
Persist — results are readable afterwards without recomputation.

API

# Run a validation (computes, pins evidence, submits on-chain) — $0.05, x402 or MPP
curl -X POST "https://validator.credprotocol.com/v1/validate/0xADDRESS?chain_id=8453&submit_onchain=true&submit_reputation=true"

# Read the latest stored validation for a wallet (free)
curl "https://validator.credprotocol.com/v1/validate/0xADDRESS/latest?chain_id=8453"

# Read by ERC-8004 agent ID (free)
curl "https://validator.credprotocol.com/v1/validate/agent/42?chain_id=8453"

# Which payment rails are enabled right now
curl https://validator.credprotocol.com/v1/payment-methods

Example response:

{
  "agent_wallet": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
  "agent_id": 0,
  "chain_id": 8453,
  "composite_score": 75,
  "verified": true,
  "trust_level": "high",
  "confidence": "partial",
  "breakdown": {
    "credit":   { "raw_score": 772, "normalized": 67.4, "weight": 0.4 },
    "sybil":    { "raw_score": 16,  "normalized": 84,   "weight": 0.3 },
    "identity": { "raw_attestations": null, "normalized": null, "weight": 0.3 }
  },
  "evidence_cid": "QmWB3dQsQxDALFhDKc5DzuvL62N4rYRQXMWEvh2rfJrdq4",
  "evidence_url": "https://gateway.pinata.cloud/ipfs/QmWB3dQsQxDALFhDKc5DzuvL62N4rYRQXMWEvh2rfJrdq4",
  "tx_hash": null,
  "tx_status": "pending"
}

POST /v1/validate/{address} without payment returns 402 with x402 (X-PAYMENT-REQUIRED) and MPP (WWW-Authenticate: Payment …) challenges — see Machine Payments. Everything else above is free. Full OpenAPI: validator.credprotocol.com/docs.

Agents API — discover agents in the ERC-8004 Identity Registry and read/submit reputation from the main API (/api/v2/agents/*).
MCP Services — the same tools for MCP-native agents.
ERC-8004 specification.

Get Started

Use Cases

Guides

On-Chain Reputation

Composite score

Trust levels

Confidence

Pipeline

API

​Composite score

​Trust levels

​Confidence

​Pipeline

​API

​Related

Composite score

Trust levels

Confidence

Pipeline

API

Related