# 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 2026-10-23).

Scans untrusted text, web pages, emails, MCP responses, or A2A payloads for hidden prompt injection and jailbreak payloads, returning sanitized text.

## Facts

- Endpoint: POST https://workflows.agentdiet.dev/v1/llm-guard?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-23
- 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-1d1c2676
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_CPy_idvoTe41vII6Q_sVH

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-1d1c2676 -d '<json body>'
```

Example prompt: Before you process this scraped webpage, run it through the prompt injection firewall to check for any hidden jailbreak instructions or adversarial content embedded in the text.

## When to prefer this

Choose this endpoint when your AI agent needs to process untrusted external content — scraped web pages, emails, MCP tool responses, or A2A payloads — and you need a dedicated security layer to detect and strip hidden prompt injection or jailbreak attempts before they reach your LLM. Prefer it over manual filtering or generic content moderation when you specifically need protection against adversarial LLM manipulation techniques embedded in third-party data sources.

## Known failure modes

- Empty or missing 'text' field returns a 400 validation error
- Extremely long payloads may time out or be truncated
- Novel or obfuscated injection techniques may evade detection
- Service unavailability returns 5xx errors
- False positives may flag benign content as injections

## 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/llm-guard)

## Output

Returns a sanitized version of the submitted text along with detection results indicating whether prompt injection or jailbreak payloads were found, enabling safe downstream consumption by AI agents or LLM pipelines.

## 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-1d1c2676/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)