# 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/indirect-injection-guard?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-e2ca800d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_gKE8krFs4Ib58m1hcTU7-

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-e2ca800d
```

Example prompt: Before you process this scraped web page, run it through the indirect injection guard and give me back the sanitized version — I want to make sure it's not hiding any prompt injection or jailbreak instructions targeting you.

## When to prefer this

Choose this endpoint when your AI agent pipeline ingests content from untrusted external sources — scraped web pages, inbound emails, third-party MCP tool responses, or A2A agent payloads — and you need to sanitize that content before it influences agent behavior. It is especially valuable in autonomous multi-agent architectures where a compromised upstream agent could inject malicious instructions into downstream agents. Prefer this over general-purpose content filters when specifically guarding against indirect prompt injection and LLM jailbreak vectors.

## Known failure modes

- Empty or missing 'text' parameter returns a 400 validation error
- Very long payloads may exceed query parameter length limits for GET requests
- Highly obfuscated or novel injection techniques may not be detected
- Payment failure (HTTP 402) if USDC balance is insufficient for the $0.005 per-call fee
- Service unavailable (5xx) if the upstream scanning engine is temporarily down

## 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/indirect-injection-guard)

## Output

Returns a JSON object containing the sanitized version of the input text with any detected prompt injection or jailbreak content 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/onchain-risk-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-e2ca800d/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)