# A2A Indirect Prompt-Injection & Jailbreak Firewall

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

## Facts

- Endpoint: GET https://sec-intel.agentdiet.dev/v1/injection-guard?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: sec-intel.agentdiet.dev
- Website: https://sec-intel.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/sec-intel-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-dd7401b0
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_oI3z0ON1Jti9nUm-r-k_U

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 sec-intel-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-dd7401b0
```

Example prompt: Before you process that scraped web page, run its content through the injection-guard firewall to check for any hidden prompt injections or jailbreak instructions embedded in the HTML.

## When to prefer this

Choose this endpoint when your AI agent pipeline ingests content from untrusted external sources — web scraping, inbound emails, third-party MCP responses, or A2A payloads — and you need a dedicated security layer to detect and strip hidden prompt injections or jailbreak instructions before that content reaches your LLM. Prefer this over generic content filters when you specifically need adversarial prompt-injection detection tailored to the A2A/MCP agent security context.

## Known failure modes

- Empty or missing 'text' parameter returns a validation error
- Extremely long text inputs may be truncated or rejected
- False negatives possible for novel or obfuscated injection techniques
- Rate limiting or payment failure (HTTP 402) if x402 micropayment is not fulfilled
- Service unavailability returns 5xx error

## 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://sec-intel.agentdiet.dev/v1/injection-guard)

## Output

Returns a structured object containing the sanitized version of the input text with any detected prompt injection or jailbreak payloads removed or flagged, along with detection signals indicating whether an attack was 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/sec-intel-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-dd7401b0/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from sec-intel.agentdiet.dev](https://www.zero.xyz/host/sec-intel.agentdiet.dev/llms.txt)