# SignalLayer Agent Preflight Check

> SignalLayer Agent Preflight Check is a paid API for AI agents from signallayer.floot.app, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-19).

Pre-flight safety check that scores and verdicts a target URL or Base EVM address before an autonomous agent spends money or interacts with it

## Facts

- Endpoint: GET https://signallayer.floot.app/_api/v1/agent/preflight?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-19
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/signallayer-agent-preflight-check-aa062bfc
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_wplQd8GPWe7ln9cCWPPtY

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 signallayer-agent-preflight-check-aa062bfc
```

Example prompt: Before my agent pays that endpoint at https://payments.example.com, run a preflight safety check on it — treat the intent as 'pay', use the Base network (eip155:8453), and flag it if the price would exceed $0.05.

## When to prefer this

Use this endpoint when an autonomous agent needs a machine-readable trust signal before committing to any on-chain payment, transfer, or interaction on Base. Prefer it over generic URL checkers when you need a combined risk score plus blockchain-aware context, especially when operating in a pay-per-call x402 environment where false positives cost money.

## Known failure modes

- Target URL or address is unreachable or malformed — endpoint may return an error or low-confidence result
- Network CAIP-2 identifier is unsupported or mismatched — validation may fail
- Stale or cached result if freshness maxAgeSeconds has elapsed since last check
- Missing required 'intent' or 'target' query parameters — request rejected
- Target is a known malicious address — verdict 'fail' returned with warnings populated

## How this service works

Machine-native decision and data primitives for autonomous agents, paid per call with x402 V2 USDC on Base.

## Output

Returns a decision object with a numeric safety score (0-100), a verdict ('pass' or equivalent), a confidence value between 0 and 1, an array of warnings, and a freshness block showing when the check was performed and how long results are valid.

## 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"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "intent": {
       "enum": [
        "pay",
        "interact",
        "transfer",
        "unknown"
       ],
       "type": "string"
      },
      "target": {
       "type": "string",
       "description": "Public http(s) resource URL or Base EVM address to inspect before spending."
      },
      "network": {
       "type": "string",
       "description": "Expected CAIP-2 network, e.g. eip155:8453."
      },
      "maxPriceUsd": {
       "type": "number",
       "minimum": 0
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "tool": "agent_preflight",
  "status": "complete",
  "decision": {
   "score": 92,
   "verdict": "pass",
   "confidence": 0.93
  },
  "warnings": [],
  "freshness": {
   "checkedAt": "2026-10-06T00:00:00.000Z",
   "maxAgeSeconds": 30
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/signallayer-agent-preflight-check-aa062bfc/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from signallayer.floot.app](https://www.zero.xyz/host/signallayer.floot.app/llms.txt)