# A2A Indirect Prompt-Injection & Jailbreak Firewall

> A2A Indirect Prompt-Injection & Jailbreak Firewall is a paid API for AI agents from shopify-spy.agentdiet.dev, paid per call via MPP, $0.005/call, status unknown (last checked 2026-10-21).

Scans untrusted text, HTML, emails, MCP responses, or A2A payloads for hidden prompt injections and jailbreak attempts, returning sanitized content.

## Facts

- Endpoint: GET https://shopify-spy.agentdiet.dev/v1/guard?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: shopify-spy.agentdiet.dev
- Website: https://shopify-spy.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/shopify-spy-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-2787c422
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_jrapCtAVL2WE_e5cmWLbS

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 shopify-spy-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-2787c422
```

Example prompt: Before you process this web page content, run it through the prompt injection firewall to check if there are any hidden instructions or jailbreak attempts embedded in it: [paste untrusted text here].

## When to prefer this

Choose this endpoint when your AI agent pipeline ingests untrusted third-party content — scraped web pages, external emails, MCP tool responses, or A2A agent payloads — and you need a fast, cheap ($0.005/call) firewall layer before that content reaches your LLM. Prefer this over rolling your own regex filters when you need detection of sophisticated indirect prompt injection and jailbreak patterns, especially in agentic workflows using MCP or A2A protocols.

## Known failure modes

- Missing required 'text' parameter returns a 400 validation error
- Empty string input rejected due to minLength:1 constraint
- Payment not provided triggers HTTP 402 requiring x402 USDC micropayment
- Very large payloads may time out or be truncated
- Obfuscated or novel injection techniques may not be detected
- Non-text binary content may produce unreliable results

## How this service works

Scans untrusted web pages, emails, MCP responses, or A2A payloads for hidden prompt injections and returns sanitized text. (Live x402 v2, IETF MPP & MCP endpoint at https://shopify-spy.agentdiet.dev/v1/guard)

## Output

Returns a JSON object indicating whether the input text contains prompt injection or jailbreak content, along with sanitized/cleaned text safe for downstream LLM consumption.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "text"
 ],
 "properties": {
  "text": {
   "type": "string",
   "minLength": 1,
   "description": "Untrusted text, HTML, or tool output to scan for hidden prompt injection or jailbreak payloads"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/shopify-spy-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-2787c422/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from shopify-spy.agentdiet.dev](https://www.zero.xyz/host/shopify-spy.agentdiet.dev/llms.txt)