# A2A Indirect Prompt-Injection & Jailbreak Firewall

> A2A Indirect Prompt-Injection & Jailbreak Firewall is a paid API for AI agents from serp-extract.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://serp-extract.agentdiet.dev/v1/injection-guard?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-23
- Activations on Zero: 0
- Provider: serp-extract.agentdiet.dev
- Website: https://serp-extract.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/serp-extract-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-bf2599d7
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_WRXL9WSJrRF28QPrS09if

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 serp-extract-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-bf2599d7 -d '<json body>'
```

Example prompt: Before you process this web page I just scraped, run it through the prompt injection firewall first — I want to make sure there are no hidden instructions trying to hijack your behavior buried in the HTML.

## When to prefer this

Choose this endpoint when your AI agent is consuming untrusted external content — scraped web pages, user-submitted text, third-party API responses, MCP tool outputs, or A2A payloads — and you need to screen for hidden prompt injections or jailbreak instructions before passing that content into the LLM context. It is especially valuable in agentic pipelines where external data sources could be adversarially crafted to hijack agent behavior.

## Known failure modes

- Empty or missing 'text' field returns a validation error
- Extremely large payloads may time out or be truncated
- Payment failure via x402 results in HTTP 402 if USDC balance is insufficient
- Highly obfuscated or novel injection techniques may evade detection
- Non-UTF8 or malformed HTML 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://serp-extract.agentdiet.dev/v1/injection-guard)

## Output

A JSON object containing the scan result for the submitted text, indicating whether prompt injection or jailbreak content was detected and providing sanitized text safe for downstream agent 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/serp-extract-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-bf2599d7/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from serp-extract.agentdiet.dev](https://www.zero.xyz/host/serp-extract.agentdiet.dev/llms.txt)