# A2A Indirect Prompt-Injection & Jailbreak Firewall

> A2A Indirect Prompt-Injection & Jailbreak Firewall is a paid API for AI agents from token-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 output.

## Facts

- Endpoint: GET https://token-intel.agentdiet.dev/v1/mcp-injection-firewall?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: token-intel.agentdiet.dev
- Website: https://token-intel.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/token-intel-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-9f2c503e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_D4LesUicoR-Kd74kyPzCs

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 token-intel-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-9f2c503e
```

Example prompt: Before you process that scraped webpage, run the raw HTML through the prompt-injection firewall first — I want to make sure there are no hidden instructions or jailbreak payloads embedded in it.

## When to prefer this

Choose this endpoint when your AI agent is about to process untrusted external content — web pages, emails, MCP tool responses, or A2A payloads — and you need to detect and strip hidden prompt injections or jailbreak attempts before they can influence agent behavior. Ideal for multi-agent pipelines where intermediary tool outputs cannot be fully trusted, or when scraping adversarial web content. Prefer this over generic content filters when you specifically need LLM-aware injection detection rather than simple spam or malware scanning.

## Known failure modes

- Empty or missing 'text' parameter returns a validation error
- Extremely long input text may exceed processing limits
- Ambiguous or benign-looking injections may evade detection (false negatives)
- Network timeout for very large payloads
- Rate limiting or payment failure via x402 if USDC balance is insufficient

## 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://token-intel.agentdiet.dev/v1/mcp-injection-firewall)

## 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 metadata indicating whether malicious content 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/token-intel-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-9f2c503e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from token-intel.agentdiet.dev](https://www.zero.xyz/host/token-intel.agentdiet.dev/llms.txt)