# A2A Indirect Prompt-Injection & Jailbreak Firewall

> A2A Indirect Prompt-Injection & Jailbreak Firewall is a paid API for AI agents from token-intel.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 content.

## Facts

- Endpoint: GET https://token-intel.agentdiet.dev/v1/llm-guard?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: token-intel.agentdiet.dev
- Website: https://token-intel.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/token-intel-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-83ef72d1
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_MDSld4nPGRNo9C5jLojHl

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 token-intel-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-83ef72d1
```

Example prompt: Before you process this scraped webpage content, run it through the prompt-injection firewall to check for hidden jailbreak instructions and give me the sanitized version: [paste content here].

## When to prefer this

Choose this endpoint when your AI agent needs to safely ingest content from untrusted external sources — web scrapes, emails, third-party API responses, MCP payloads, or A2A messages — before passing them to an LLM. It is specifically designed for the indirect prompt-injection attack vector where malicious instructions are hidden inside seemingly benign content, rather than injected directly into a user prompt.

## Known failure modes

- Empty or missing 'text' parameter returns a 400 validation error
- Very long payloads may exceed request size limits
- Obfuscated or encoded injections may evade detection
- Payment not processed (402) blocks the request
- False positives may strip legitimate content resembling injection patterns
- Network timeout on large HTML documents

## 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://token-intel.agentdiet.dev/v1/llm-guard)

## Output

Returns a JSON object indicating whether prompt injection or jailbreak content was detected, along with sanitized text stripped of malicious instructions, allowing the agent to safely process the cleaned output.

## 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/token-intel-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-83ef72d1/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from token-intel.agentdiet.dev](https://www.zero.xyz/host/token-intel.agentdiet.dev/llms.txt)