# AstraNL Spend Fuse – Budget Audit & Spending Verdict

> AstraNL Spend Fuse – Budget Audit & Spending Verdict is a paid API for AI agents from verify.astranl.com, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-11).

Evaluates a payment intent against spending rules and returns a STOP/PASS verdict indicating whether the spend should be allowed or blocked.

## Facts

- Endpoint: GET https://verify.astranl.com/v1/spend-fuse?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/astranl-spend-fuse-budget-audit-spending-verdict-5281f6d5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap__P9rldl9acJmDyF4-FmTw

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 astranl-spend-fuse-budget-audit-spending-verdict-5281f6d5
```

Example prompt: Before I approve this $12.50 payment, run a spend fuse check on intent id 'pi_abc123' to see whether it gets a STOP or PASS verdict.

## When to prefer this

Choose this endpoint when you need a lightweight, low-cost ($0.002 per call) pre-execution budget gate for agent-initiated payments. It is ideal for autonomous AI agents that need a rule-based STOP/PASS verdict before committing a spend, especially when operating under budget caps or compliance rules. Prefer this over general payment APIs when the goal is audit/verification rather than execution.

## Known failure modes

- Missing required 'amount_usd' query parameter returns a validation error
- Invalid or malformed intent_id may result in an unrecognized intent response
- Paid endpoint — missing x402 payment header results in 402 Payment Required
- Unsupported HTTP method (not GET/HEAD/DELETE) returns 405 Method Not Allowed
- Amount provided in wrong format (non-string or non-numeric string) causes schema rejection

## How this service works

The Crossing moves look, claim, release, mark and check are free and need no account. The other paths are paid per call over x402, USDC on Base. Operator AstraNL, KvK 88449335.

## Output

Returns a JSON object with a 'kind' of 'spend_fuse', a 'result' containing a list of stops (rule codes that triggered), a list of checks performed, and a 'verdict' of either STOP or PASS. A receipt object is also included. Example: {kind:'spend_fuse', result:{stops:['F5'], checks:[], verdict:'STOP'}, receipt:{}}

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "amount_usd"
     ],
     "properties": {
      "intent_id": {
       "type": "string",
       "description": "stable id of this payment intent; 20 inputs in total, see the protocol"
      },
      "amount_usd": {
       "type": "string",
       "description": "the spend, USD"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "kind": "spend_fuse",
  "result": {
   "stops": [
    "F5"
   ],
   "checks": [],
   "verdict": "STOP"
  },
  "receipt": {}
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/astranl-spend-fuse-budget-audit-spending-verdict-5281f6d5/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from verify.astranl.com](https://www.zero.xyz/host/verify.astranl.com/llms.txt)