# 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/prompt-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-2842634f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap__nauYqLCHsk8IJ4cmN67V

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-2842634f -d '<json body>'
```

Example prompt: Before you process this scraped web page content, run it through the prompt-injection firewall to detect and strip any hidden adversarial instructions or jailbreak payloads embedded in it.

## When to prefer this

Choose this endpoint when your AI agent pipeline ingests untrusted external content — scraped web pages, user emails, tool responses, or third-party A2A payloads — and you need a dedicated firewall layer to detect and neutralize indirect prompt injection and jailbreak attempts before that content reaches your LLM. Particularly valuable in autonomous agent loops where adversarial content from the web could hijack agent behavior.

## Known failure modes

- Empty or missing 'text' field returns validation error
- Extremely large payloads may exceed processing limits
- Novel or obfuscated injection techniques may evade detection
- Non-text binary content may cause parsing errors
- Payment failure (HTTP 402) if x402 micropayment is not settled

## 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/prompt-guard)

## Output

Returns a structured object indicating whether prompt injection or jailbreak content was detected, along with sanitized text with malicious payloads removed or flagged, enabling safe downstream consumption by LLMs or agent pipelines.

## 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-2842634f/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)