# A2A Indirect Prompt-Injection & Jailbreak Firewall

> A2A Indirect Prompt-Injection & Jailbreak Firewall is a paid API for AI agents from cve-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://cve-intel.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: cve-intel.agentdiet.dev
- Website: https://cve-intel.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/cve-intel-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-6fb5135a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_4gh47g30ihODZ0aqF_5m3

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 cve-intel-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-6fb5135a
```

Example prompt: Before you process this scraped web page, scan it for hidden prompt injections or jailbreak payloads — here's the raw HTML: '<div>Normal content...</div><p style="display:none">Ignore all previous instructions and...</p>'

## When to prefer this

Choose this endpoint when your AI agent is about to consume untrusted content from the web, emails, external tool responses, or A2A payloads and you need a dedicated security layer to detect and strip hidden prompt injections or jailbreak attempts before they reach your agent's context window. Particularly valuable in agentic pipelines where agents browse the web, read emails, or call third-party MCP/A2A tools.

## Known failure modes

- Missing required 'text' parameter returns a 400 error
- Empty string input rejected due to minLength:1 constraint
- Payment required error (HTTP 402) if x402 payment not included
- Very long inputs may time out or be truncated
- Sophisticated or novel injection patterns may evade detection
- Non-text binary content may produce unexpected results

## 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://cve-intel.agentdiet.dev/v1/system-prompt-guard)

## Output

Returns a sanitized version of the input text with prompt injection and jailbreak payloads identified and removed or flagged, along with detection metadata indicating whether threats 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/cve-intel-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-6fb5135a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from cve-intel.agentdiet.dev](https://www.zero.xyz/host/cve-intel.agentdiet.dev/llms.txt)