# A2A Indirect Prompt-Injection & Jailbreak Firewall

> A2A Indirect Prompt-Injection & Jailbreak Firewall is a paid API for AI agents from x402-audit.agentdiet.dev, paid per call via MPP, $0.005/call, status unknown.

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

## Facts

- Endpoint: POST https://x402-audit.agentdiet.dev/v1/injection-guard?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP
- Status: unknown
- Activations on Zero: 0
- Provider: x402-audit.agentdiet.dev
- Website: https://x402-audit.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/x402-audit-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-9df747ae
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_iAhVRIk0KUMPaqN7FVWHf

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 x402-audit-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-9df747ae -d '<json body>'
```

Example prompt: Before you summarize that webpage content, run it through the injection-guard firewall first — I want to make sure there are no hidden prompt injection or jailbreak instructions embedded in it.

## When to prefer this

Use this endpoint when an AI agent is about to process content from untrusted external sources — scraped web pages, third-party API responses, MCP tool outputs, A2A payloads, or user-submitted emails — and you need to strip or flag hidden prompt injection or jailbreak instructions before they reach the LLM. Prefer this over general content moderation tools when the threat model is specifically adversarial prompt injection in agentic pipelines.

## Known failure modes

- Empty or missing 'text' field returns a validation error
- Extremely large payloads may be rejected or truncated
- Sophisticated obfuscation techniques may evade detection
- Payment required (HTTP 402) if x402 micropayment header is absent
- Network timeout for very long text inputs

## 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://x402-audit.agentdiet.dev/v1/injection-guard)

## Output

Returns a sanitized version of the submitted text with prompt injection and jailbreak payloads removed or flagged, along with detection metadata indicating whether malicious instructions were 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/x402-audit-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-9df747ae/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-audit.agentdiet.dev](https://www.zero.xyz/host/x402-audit.agentdiet.dev/llms.txt)