# SignalHarness Token Allowance Change Analyzer

> SignalHarness Token Allowance Change Analyzer is a paid API for AI agents from signalharness.ai, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-16).

Analyzes a token allowance change request and returns a structured assessment with warnings and evidence scope

## Facts

- Endpoint: POST https://signalharness.ai/api/agent/services/token_allowance_change/invoke
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/signalharness-token-allowance-change-analyzer-c3ea2a7b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_6Dz9d1Ysxn9ErmwmikjRu

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-token-allowance-change-analyzer-c3ea2a7b -d '<json body>'
```

Example prompt: Can you analyze this token allowance change request and tell me if there are any warnings or risks I should know about: 'Uniswap is requesting unlimited USDC allowance on Base mainnet for my wallet'?

## When to prefer this

Choose this endpoint when you need a quick, structured AI-powered analysis of a token allowance change request — especially in agentic or automated DeFi workflows where an agent must decide whether to proceed with or flag an on-chain approval. It is particularly useful when you want machine-readable warnings and an evidence scope label alongside the narrative analysis, and when operating on Base network with USDC micropayment billing via x402.

## Known failure modes

- Input string too short (below 2 characters) or too long (above 65536 characters) causing validation failure
- Malformed or ambiguous allowance request text resulting in incomplete analysis
- Payment failure on the x402 protocol leading to unpaid/rejected call
- Network or service unavailability returning a non-succeeded status
- Insufficient context in the request causing vague or low-confidence analysis output

## 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 containing: an allowance_change_analysis narrative, a list of warnings, an evidence_scope label ('caller_supplied_data'), replay status, and a full receipt with payment details, request/execution IDs, result hash, and settlement reference on the Base network.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "replay": false,
  "result": {
   "warnings": [
    "Allowance records are caller supplied and may be stale."
   ],
   "service_id": "token_allowance_change",
   "evidence_scope": "caller_supplied_data",
   "allowance_change_analysis": "{\"decreases\":0,\"increases\":1,\"records\":[{\"after_atomic\":\"2\",\"before_atomic\":\"1\",\"delta_atomic\":\"1\",\"direction\":\"increase\",\"owner\":\"0x0000000000000000000000000000000000000001\",\"spender\":\"0x0000000000000000000000000000000000000002\",\"unlimited_after\":false}],\"unlimited_after\":0}"
  },
  "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": "token_allowance_change",
   "executionId": "example-execution",
   "startedAtMs": 0,
   "amountAtomic": "10000",
   "resultSha256": "faf38a66d32ed5da0dc78115ccd3495c6b37cf131d643f756e6fd3d86fd0397e",
   "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-token-allowance-change-analyzer-c3ea2a7b/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)