# A2A Indirect Prompt-Injection & Jailbreak Firewall

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

## Facts

- Endpoint: GET https://onchain-risk.agentdiet.dev/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: onchain-risk.agentdiet.dev
- Website: https://onchain-risk.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/onchain-risk-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-c6f9aa7b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_6bqAgQXT9NDELG8qpPddE

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 onchain-risk-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-c6f9aa7b
```

Example prompt: Before you summarize this webpage I just scraped, can you run the raw HTML through the prompt injection firewall to make sure there are no hidden jailbreak instructions embedded in it that could hijack you?

## When to prefer this

Use this endpoint when your AI agent needs to process untrusted external content — scraped web pages, third-party emails, external tool responses, or A2A messages — before feeding it to an LLM. Particularly valuable in agentic pipelines where indirect prompt injection is a real threat vector, such as autonomous browsing agents, email-processing agents, or multi-agent orchestration systems. Prefer this over generic content filters when your specific concern is LLM hijacking and jailbreak payloads rather than general spam or NSFW content.

## Known failure modes

- Empty or missing 'text' parameter returns validation error
- Extremely large text payloads may time out or be truncated
- Sophisticated obfuscated injections may evade detection (false negatives)
- Non-text binary content may not be parseable
- Payment failure (402) if x402 USDC micropayment is not completed

## 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://onchain-risk.agentdiet.dev/v1/llm-jailbreak-defense)

## Output

Returns a JSON object indicating whether prompt injection or jailbreak content was detected, along with sanitized text with malicious instructions removed or flagged, suitable for safe downstream 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/onchain-risk-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-c6f9aa7b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from onchain-risk.agentdiet.dev](https://www.zero.xyz/host/onchain-risk.agentdiet.dev/llms.txt)