# Polygon Event Sequence Analyzer

> Polygon Event Sequence Analyzer is a paid API for AI agents from signalharness.ai, paid per call via x402, $0.015/call, status unknown (last checked 2026-09-13).

Analyzes and deterministically orders a supplied set of Polygon PoS blockchain events by block number, transaction index, and log index to detect ambiguous ordering.

## Facts

- Endpoint: POST https://signalharness.ai/api/agent/services/polygon_event_sequence_analyze/invoke
- Price: $0.015/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/polygon-event-sequence-analyzer-8433a175
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_FE_ZJThvsyuX_JkDPGbKw

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 polygon-event-sequence-analyzer-8433a175 -d '<json body>'
```

Example prompt: I have a list of Polygon PoS smart contract events with their block numbers, transaction indexes, and log indexes — can you analyze whether they're in unambiguous chronological order and give me the sorted sequence?

## When to prefer this

Choose this endpoint when you need deterministic, rule-based sequencing of Polygon PoS blockchain events from caller-supplied data — without making live RPC calls to a node. Ideal when you already have raw event data and need to verify or sort it by canonical on-chain ordering (block → tx index → log index). Prefer this over generic blockchain indexers when you need explicit ordering ambiguity detection and network-context metadata for Polygon PoS or Amoy testnet (chain IDs 137 and 80002).

## Known failure modes

- Supplied event data missing required indexes (block_number, log_index, transaction_index) causing warnings or incorrect ordering
- Events from unsupported chain IDs (only 137 and 80002 accepted) may fail validation
- Malformed request_json string causing parse errors
- Ambiguous ordering flagged when events share identical block, transaction, and log index values
- Empty event array returning zero-count result with no sequence

## 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 analysis containing the ordered list of events with their source indexes, an ambiguous_order boolean flag, total event count, network context (accepted chain IDs, bridge model, completion policy, protocol family), and any warnings about index-dependent ordering. Also returns the analyzed network identifier and evidence scope.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "replay": false,
  "result": {
   "warnings": [
    "Ordering depends on supplied indexes."
   ],
   "service_id": "polygon_event_sequence_analyze",
   "analysis_json": "{\"ambiguous_order\":false,\"count\":1,\"events\":[{\"_source_index\":0,\"address\":\"0x0000000000000000000000000000000000000001\",\"block_number\":1,\"chain\":\"137\",\"log_index\":0,\"transaction_index\":0}],\"network_context\":{\"accepted_chain_ids\":[\"137\",\"80002\"],\"bridge_model\":\"root-child state sync plus checkpoint evidence\",\"completion_policy\":\"never inferred without supplied evidence\",\"protocol_family\":\"Polygon PoS\"}}",
   "evidence_scope": "caller_supplied_data",
   "analyzed_network": "polygon"
  },
  "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": "polygon_event_sequence_analyze",
   "executionId": "example-execution",
   "startedAtMs": 0,
   "amountAtomic": "15000",
   "resultSha256": "6d330a8c3eb84f1f9c1efa0e8f9b218582f8492f382e3b9090c03d3b226f55fb",
   "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/polygon-event-sequence-analyzer-8433a175/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)