# 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 2026-10-23).

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

## Facts

- Endpoint: POST https://shopify-spy.agentdiet.dev/v1/prompt-guard?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-23
- 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-15289e2c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_CBKJ1wWJPWypXZ5JoFCaV

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-15289e2c -d '<json body>'
```

Example prompt: Before you process this HTML page I scraped, can you run it through the prompt-injection firewall to check for any hidden jailbreak or indirect prompt injection payloads and give me the sanitized version?

## When to prefer this

Choose this endpoint when your AI agent pipeline ingests text from untrusted external sources — scraped web pages, user-submitted content, third-party API responses, emails, or MCP/A2A messages — and you need to sanitize them before passing to an LLM. It is specifically designed for A2A and agent-to-agent security contexts, making it more targeted than a generic content moderation API.

## Known failure modes

- Empty or whitespace-only text input returns a validation error
- Extremely large payloads may exceed processing limits or time out
- Obfuscated or novel injection techniques may evade detection
- Payment required (HTTP 402) if x402 micropayment header is missing or invalid
- Non-UTF-8 encoded content may cause parsing errors

## 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/prompt-guard)

## Output

Returns a sanitized version of the input text with hidden prompt injection and jailbreak payloads detected and removed or flagged, along with detection metadata indicating whether any malicious content was found.

## 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-15289e2c/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)