# A2A Indirect Prompt-Injection & Jailbreak Firewall

> A2A Indirect Prompt-Injection & Jailbreak Firewall is a paid API for AI agents from json-repair.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 output.

## Facts

- Endpoint: GET https://json-repair.agentdiet.dev/v1/guard?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: json-repair.agentdiet.dev
- Website: https://json-repair.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/json-repair-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-ba8a2944
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_YYle3Vm8LRhAuAUy-6VBx

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 json-repair-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-ba8a2944
```

Example prompt: Before you process that scraped web page, run it through the prompt-injection firewall to check for any hidden jailbreak instructions embedded in the HTML and give me back the sanitized version.

## When to prefer this

Choose this endpoint when your AI agent is about to consume untrusted external content — scraped web pages, incoming emails, third-party API or MCP tool responses, or A2A payloads — and you need a lightweight, fast guard layer to detect and strip hidden prompt-injection or jailbreak instructions before the agent acts on them. Prefer it over manual regex filtering or generic content moderation when the threat model is specifically adversarial LLM manipulation rather than toxicity or spam.

## Known failure modes

- Empty or missing 'text' parameter returns a validation error
- Extremely large payloads may be rejected or truncated
- False negatives possible for highly obfuscated or novel injection techniques
- Network timeout if the service is temporarily unavailable
- Non-UTF-8 encoded content may cause parsing errors

## 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://json-repair.agentdiet.dev/v1/guard)

## Output

Returns a JSON object indicating whether prompt injection or jailbreak content was detected in the input, along with a sanitized version of the text with adversarial instructions removed or flagged.

## 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/json-repair-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-ba8a2944/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from json-repair.agentdiet.dev](https://www.zero.xyz/host/json-repair.agentdiet.dev/llms.txt)