# ERC-8004 Agent Trust Score Explanation

> ERC-8004 Agent Trust Score Explanation is a paid API for AI agents from api.8k4protocol.com, paid per call via x402, $0.001/call, status down (last checked 2026-08-24).

Returns a human-readable explanation of an agent's ERC-8004 trust score, including positive factors and cautions driving the score

## Facts

- Endpoint: GET https://api.8k4protocol.com/agents/21480/score/explain
- Price: $0.001/call
- Payment: x402
- Status: down
- Last checked: 2026-08-24
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/api-8k4protocol-com-16da80b7
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_7_-TPdPSRrTLiL8ZiVMcU

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability api-8k4protocol-com-16da80b7
```

Example prompt: Can you explain the ERC-8004 trust score for agent 21480 on this chain — what are the positive signals and what cautions are flagged?

## When to prefer this

Use this endpoint when you need to understand the reasoning behind an agent's ERC-8004 trust score, not just the numeric value. Prefer this over the raw score endpoint when a user wants to audit, compare, or explain why an agent is trusted or flagged.

## Known failure modes

- Agent ID not found — returns 404 or empty result
- Invalid chain ID — returns error indicating unsupported or unknown chain
- Agent has no score yet — returns empty or null explanation
- Network/RPC issues causing timeout
- Insufficient payment — x402 payment required error

## How this service works

Get score explanation with positives and cautions

## Output

A structured explanation of the agent's ERC-8004 trust score, listing specific positive factors that contributed to the score and cautions or risk signals that may be lowering it, helping users understand exactly why the agent received its rating.

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/api-8k4protocol-com-16da80b7/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.8k4protocol.com](https://www.zero.xyz/host/api.8k4protocol.com/llms.txt)