# SignalHarness EVM Block Analyzer

> SignalHarness EVM Block Analyzer is a paid API for AI agents from signalharness.ai, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-13).

Analyzes a supplied EVM block (or block-related data) and returns a structured analysis with warnings and evidence scope

## Facts

- Endpoint: POST https://signalharness.ai/api/agent/services/evm_block_analyze/invoke
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/signalharness-evm-block-analyzer-5c000fd8
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_PJSBEduqPiRB0PlT7WRSa

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 signalharness-evm-block-analyzer-5c000fd8 -d '<json body>'
```

Example prompt: Can you analyze this EVM block data for me and flag any warnings or anomalies? Here's the raw block payload: [block JSON or identifier]. I want a structured breakdown of what happened in that block.

## When to prefer this

Choose this endpoint when you need AI-powered semantic analysis of EVM block data — particularly for detecting anomalies, extracting structured insights, or auditing on-chain activity at the block level. Prefer it over raw RPC calls when you want interpreted results with warnings rather than raw block JSON. Suitable for agents that need to reason about block contents without implementing their own parsing logic.

## Known failure modes

- Invalid or malformed evm_block_request string returns an error
- Block data exceeding 65536 characters will be rejected
- Payment failure or insufficient USDC balance prevents execution
- Ambiguous or incomplete block data may result in low-confidence analysis with broad warnings
- Network issues may cause timeout with no result

## How this service works

Explore 330 pay-per-call x402 API services and 27 agent-native digital products, with Base USDC pricing, secure Polar checkout, and free discovery.

## Output

Returns a JSON object with a block_analysis narrative, a list of warnings (strings), an evidence_scope field indicating the data provenance (e.g. 'caller_supplied_data'), a status field ('succeeded'), and a signed receipt containing payment details, latency, a SHA-256 result hash, and execution metadata.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "evm_block_request": {
   "type": "string",
   "maxLength": 65536,
   "minLength": 2
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "replay": false,
  "result": {
   "warnings": [
    "The supplied block is not independently validated or fetched."
   ],
   "service_id": "evm_block_analyze",
   "block_analysis": "{\"gas_limit\":\"30000000\",\"gas_used\":\"21000\",\"gas_utilization\":\"0.07\",\"hash\":\"0xbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb\",\"number\":\"100\",\"parent_hash\":\"0xcccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc\",\"total_value_atomic\":\"10\",\"transaction_count\":1}",
   "evidence_scope": "caller_supplied_data"
  },
  "status": "succeeded",
  "receipt": {
   "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
   "usage": [],
   "status": "succeeded",
   "network": "eip155:8453",
   "artifacts": [],
   "endedAtMs": 0,
   "latencyMs": 0,
   "paymentId": "example-payment",
   "receiptId": "example-receipt",
   "requestId": "example-request",
   "serviceId": "evm_block_analyze",
   "executionId": "example-execution",
   "startedAtMs": 0,
   "amountAtomic": "10000",
   "resultSha256": "cfe50c9e1bd0310bcdd46b8cd335a0bf2f47466df90ab16977751bca1f7bc887",
   "serviceVersion": "1.0.0",
   "settlementReference": "0x0000000000000000000000000000000000000000000000000000000000000000"
  },
  "artifacts": [],
  "requestId": "example-request",
  "executionId": "example-execution"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/signalharness-evm-block-analyzer-5c000fd8/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from signalharness.ai](https://www.zero.xyz/host/signalharness.ai/llms.txt)