# A2A Indirect Prompt-Injection & Jailbreak Firewall

> A2A Indirect Prompt-Injection & Jailbreak Firewall is a paid API for AI agents from 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 injection and jailbreak attempts, returning sanitized output.

## Facts

- Endpoint: GET https://agentdiet.dev/v1/jailbreak-scan?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: agentdiet.dev
- Website: https://agentdiet.dev
- Canonical page: https://www.zero.xyz/c/agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-firewall-910dcde5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Q8wtaQ_QFfGdVV2S_yKJP

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 agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-firewall-910dcde5
```

Example prompt: Before you process that scraped webpage, can you run it through the jailbreak firewall to check for any hidden prompt injections or adversarial instructions embedded in the HTML?

## When to prefer this

Choose this endpoint when your AI agent is about to ingest content from untrusted external sources — scraped web pages, third-party emails, external MCP/A2A tool responses, or user-supplied text — and you need a lightweight firewall pass before the content influences agent behavior. It is specifically designed for the A2A and MCP agent security use case, making it more appropriate than generic content moderation APIs when the threat model is adversarial prompt injection rather than hate speech or NSFW content.

## Known failure modes

- Missing required 'text' parameter returns a 400 bad request error
- Empty string input rejected due to minLength:1 constraint
- Very large payloads may time out or be truncated
- Payment failure via x402 returns HTTP 402 and blocks the scan
- Ambiguous or encoded injections may be missed if obfuscation is novel
- Non-UTF-8 or binary 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://agentdiet.dev/v1/jailbreak-scan)

## Output

Returns a JSON object indicating whether prompt injection or jailbreak content was detected in the input text, along with a sanitized version of the 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/agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-firewall-910dcde5/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentdiet.dev](https://www.zero.xyz/host/agentdiet.dev/llms.txt)