# A2A Indirect Prompt-Injection & Jailbreak Firewall

> A2A Indirect Prompt-Injection & Jailbreak Firewall is a paid API for AI agents from x402broker.com, 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 injections and jailbreak attempts, returning sanitized output.

## Facts

- Endpoint: GET https://x402broker.com/v1/llm-jailbreak-defense?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: x402broker.com
- Website: https://x402broker.com
- Canonical page: https://www.zero.xyz/c/x402broker-com-a2a-indirect-prompt-injection-jailbreak-firewall-39cb62ba
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Lj5R7_UUqSGsAQzeO9sJV

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 x402broker-com-a2a-indirect-prompt-injection-jailbreak-firewall-39cb62ba
```

Example prompt: Before you process that scraped webpage content, run it through the prompt injection firewall to check for any hidden jailbreak instructions embedded in the HTML — here's the raw text: [paste content].

## When to prefer this

Choose this endpoint when your AI agent pipeline ingests untrusted external content — scraped web pages, inbound emails, third-party API responses, MCP tool outputs, or A2A payloads — and you need a dedicated security layer to detect and neutralize indirect prompt injection and jailbreak attempts before they reach your LLM. Prefer this over manual filtering when the content source is attacker-controllable or when operating autonomous agent workflows where injection attacks could cause significant harm.

## Known failure modes

- Empty or missing 'text' parameter returns a validation error
- Extremely long payloads may exceed size limits or time out
- Obfuscated or novel injection techniques may evade detection
- Non-text binary content may not be scannable
- Rate limiting or payment failure (HTTP 402) if USDC balance is insufficient

## 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://x402broker.com/v1/llm-jailbreak-defense)

## Output

Returns a JSON object containing the scan results for the submitted text, including whether prompt injection or jailbreak content was detected and a sanitized version of the input safe for LLM 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/x402broker-com-a2a-indirect-prompt-injection-jailbreak-firewall-39cb62ba/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402broker.com](https://www.zero.xyz/host/x402broker.com/llms.txt)