# Prompt Injection Signal Scanner for x402 Listing Descriptions

> Prompt Injection Signal Scanner for x402 Listing Descriptions is a paid API for AI agents from srv1553682.hstgr.cloud, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Scans x402 listing description metadata for prompt-injection signals, returning matched spans and context from either a cached nightly catalog scan or a live scan for unknown URLs.

## Facts

- Endpoint: POST https://srv1553682.hstgr.cloud/route/injection-scan
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/prompt-injection-signal-scanner-for-x402-listing-descriptions-10e10de5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_8S30ylYwjQE3fPmviEBjV

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 prompt-injection-signal-scanner-for-x402-listing-descriptions-10e10de5 -d '<json body>'
```

Example prompt: Can you scan the x402 listing at https://example.hstgr.cloud/some-listing for prompt injection signals — I want to see any suspicious spans or injected instructions found in its description metadata before I let my agent interact with it.

## When to prefer this

Use this endpoint when an AI agent needs to vet an x402 listing's description metadata for adversarial prompt injection before interacting with or recommending it. Prefer this over generic content moderation or phishing detection tools when the specific concern is injected instructions embedded in agentic marketplace metadata. Especially valuable in automated procurement or agent-to-agent service discovery pipelines where listings are ingested as text prompts.

## Known failure modes

- Target URL/domain/payTo not found in catalog and live scan fails — no result returned, no charge applied
- Invalid or malformed target input returns an error
- Network timeout during live scan for unknown URLs
- Empty signal list returned — absence of signals is not a safety guarantee

## How this service works

POST {target} (listing URL, domain, or payTo) -> a factual prompt-injection SIGNAL report over x402 listing DESCRIPTION metadata (the text agents ingest): the exact matched spans + context, from a nightly full-catalog scan or a live scan for unknown URLs. Reports signals, not a malicious/clean verdict; absence of signals is not a safety guarantee. Never charged on failure.

## Output

A structured report containing the exact matched spans of potential prompt-injection content found in the listing description, surrounding context for each match, and signal metadata. Sourced from a nightly full-catalog scan (for known URLs) or a live scan (for unknown URLs). No verdict of malicious/clean is given — only signals detected. No charge is applied on scan failure.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "target": {
   "type": "string"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/prompt-injection-signal-scanner-for-x402-listing-descriptions-10e10de5/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from srv1553682.hstgr.cloud](https://www.zero.xyz/host/srv1553682.hstgr.cloud/llms.txt)