# A2A Indirect Prompt-Injection & Jailbreak Firewall

> A2A Indirect Prompt-Injection & Jailbreak Firewall is a paid API for AI agents from workflows.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://workflows.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: workflows.agentdiet.dev
- Website: https://workflows.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/workflows-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-6bdbe61f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_WYAOl-WwkdqgqSl8W93sn

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 workflows-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-6bdbe61f
```

Example prompt: Before you process the content from that scraped web page, run it through the injection-guard firewall to check for hidden prompt injections or jailbreak payloads and give me the sanitized version.

## When to prefer this

Choose this endpoint when your AI agent pipeline ingests untrusted external content — scraped web pages, emails, third-party MCP/A2A tool responses, or user-submitted text — and you need a dedicated firewall step before that content influences agent behavior. It is specifically designed for agentic security contexts (A2A, MCP, indirect injection) rather than generic content moderation, making it the right choice when defending autonomous agent workflows rather than just classifying user-facing text.

## Known failure modes

- Empty or missing 'text' parameter returns a 400 validation error
- Extremely long payloads may exceed request limits or time out
- False negatives possible for novel or obfuscated injection techniques not yet in detection patterns
- Non-English or encoded injections may reduce detection accuracy
- Payment failure via x402 results in a 402 Payment Required response blocking the scan

## 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://workflows.agentdiet.dev/v1/injection-guard)

## Output

Returns a structured object indicating whether a prompt injection or jailbreak payload was detected in the input text, along with a 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/workflows-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-6bdbe61f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from workflows.agentdiet.dev](https://www.zero.xyz/host/workflows.agentdiet.dev/llms.txt)