# A2A Indirect Prompt-Injection & Jailbreak Firewall

> A2A Indirect Prompt-Injection & Jailbreak Firewall is a paid API for AI agents from whale-momentum.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://whale-momentum.agentdiet.dev/v1/tool-poisoning-shield?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: whale-momentum.agentdiet.dev
- Website: https://whale-momentum.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/whale-momentum-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-cc645bfb
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_se3b7Qt0H-T4udObYbBKT

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 whale-momentum-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-cc645bfb
```

Example prompt: Before you process that scraped webpage, run it through the prompt-injection firewall first — check this HTML for any hidden jailbreak or indirect prompt injection payloads and give me the sanitized version.

## When to prefer this

Choose this endpoint when your AI agent is consuming content from untrusted external sources — scraped web pages, external emails, third-party MCP/A2A tool responses — and you need a dedicated security layer to detect and neutralize hidden prompt injection or jailbreak payloads before they influence your agent's behavior. It is especially valuable in multi-agent pipelines where one agent's output feeds into another, creating indirect injection risk.

## Known failure modes

- Empty or missing 'text' parameter returns a validation error
- Extremely large payloads may exceed size limits or timeout
- False negatives: sophisticated obfuscated injections may not be detected
- False positives: legitimate content resembling injection patterns may be flagged
- Payment failure (HTTP 402) if x402 micropayment is not fulfilled
- Service unavailability returns 5xx error

## 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://whale-momentum.agentdiet.dev/v1/tool-poisoning-shield)

## Output

Returns a JSON object containing the scanned result, likely including a sanitized version of the input text, detection flags indicating whether prompt injection or jailbreak content was found, and potentially threat classification details.

## 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/whale-momentum-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-cc645bfb/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from whale-momentum.agentdiet.dev](https://www.zero.xyz/host/whale-momentum.agentdiet.dev/llms.txt)