# A2A Indirect Prompt-Injection & Jailbreak Firewall

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

## Facts

- Endpoint: GET https://domain-osint.agentdiet.dev/v1/system-prompt-guard?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: domain-osint.agentdiet.dev
- Website: https://domain-osint.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/domain-osint-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-5c18976e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_zqgnwdLm_0i8y4l4BLsr1

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 domain-osint-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-5c18976e
```

Example prompt: Before you summarize that web page I just scraped, run its raw HTML through the prompt-injection firewall to make sure there are no hidden instructions trying to hijack you.

## When to prefer this

Choose this endpoint when your AI agent pipeline consumes untrusted external content — scraped web pages, user emails, third-party tool outputs, MCP responses, or A2A payloads — and you need a lightweight, low-latency firewall check before the content reaches your agent's context window. Ideal for autonomous agent architectures where indirect prompt injection is a real attack surface and you need a dedicated scanning step rather than relying on the base model's own defenses.

## Known failure modes

- Empty or missing 'text' parameter returns a 400 validation error
- Extremely large payloads may time out or be truncated
- False negatives possible for novel or obfuscated injection techniques not yet in detection patterns
- Non-text binary content may produce unreliable scan results
- Rate limiting or payment failure (402) if x402 payment is not correctly attached

## 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://domain-osint.agentdiet.dev/v1/system-prompt-guard)

## Output

Returns a structured object indicating whether prompt injection or jailbreak content was detected in the submitted text, along with sanitized version of the content safe for downstream agent 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/domain-osint-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-5c18976e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from domain-osint.agentdiet.dev](https://www.zero.xyz/host/domain-osint.agentdiet.dev/llms.txt)