# A2A Indirect Prompt-Injection & Jailbreak Firewall

> A2A Indirect Prompt-Injection & Jailbreak Firewall is a paid API for AI agents from mcp-security.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 attacks, returning sanitized output.

## Facts

- Endpoint: GET https://mcp-security.agentdiet.dev/v1/rag-poison-shield?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: mcp-security.agentdiet.dev
- Website: https://mcp-security.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/mcp-security-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-4804e8ef
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_V_5ogW7dGPE4l34ms5A8S

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 mcp-security-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-4804e8ef
```

Example prompt: Before you process this scraped web page, run it through the RAG poison shield to check for any hidden prompt injections or jailbreak payloads — here's the raw HTML: '<html>...content...</html>'

## When to prefer this

Choose this endpoint when your AI agent processes content from untrusted external sources — web scraping, email ingestion, third-party tool/MCP responses, or user-supplied text — and you need to screen for indirect prompt injection or jailbreak payloads before passing the content to an LLM. It is especially suited for agentic RAG pipelines, A2A communication chains, and any workflow where adversarial content could hijack agent behavior.

## Known failure modes

- Empty or missing 'text' parameter returns a validation error
- Extremely long inputs may be truncated or rejected
- Novel/obfuscated injection techniques may evade detection
- Non-English or encoded injections may have lower detection accuracy
- x402 payment failure results in HTTP 402 before processing occurs

## 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://mcp-security.agentdiet.dev/v1/rag-poison-shield)

## Output

Returns a JSON object containing the scan result for the submitted text, including whether prompt injection or jailbreak payloads were detected and a sanitized version of the input safe for downstream LLM or agent processing.

## 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/mcp-security-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-4804e8ef/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from mcp-security.agentdiet.dev](https://www.zero.xyz/host/mcp-security.agentdiet.dev/llms.txt)