# A2A Indirect Prompt-Injection & Jailbreak Firewall

> A2A Indirect Prompt-Injection & Jailbreak Firewall is a paid API for AI agents from domain-osint.agentdiet.dev, paid per call via MPP, $0.005/call, status unknown (last checked 2026-10-23).

Scans untrusted text, HTML, emails, MCP responses, or A2A payloads for hidden prompt injections and jailbreak attempts, returning sanitized output.

## Facts

- Endpoint: POST https://domain-osint.agentdiet.dev/v1/prompt-shield?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-23
- Activations on Zero: 0
- Provider: domain-osint.agentdiet.dev
- Website: https://domain-osint.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/domain-osint-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-923e1adc
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_j7KAvwgjSVEpZVuf_bFpl

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 domain-osint-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-923e1adc -d '<json body>'
```

Example prompt: Before you process this scraped webpage content, run it through the prompt-injection firewall to check for any hidden jailbreak instructions or embedded adversarial prompts, then give me the sanitized version.

## When to prefer this

Choose this endpoint when your agent pipeline ingests content from untrusted external sources — scraped web pages, user-submitted emails, third-party MCP tool responses, or A2A agent payloads — and you need a dedicated security layer to detect and neutralize hidden prompt injection or jailbreak attempts before that content reaches your LLM. Prefer this over general-purpose text analysis endpoints when the specific threat model is adversarial instruction injection targeting AI agents.

## Known failure modes

- Empty or missing 'text' field returns a validation error
- Extremely large payloads may be truncated or rejected
- False negatives possible for novel obfuscated injection techniques
- Payment failure (HTTP 402) if x402 micropayment is not properly handled
- Timeout for very large HTML documents

## 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://domain-osint.agentdiet.dev/v1/prompt-shield)

## Output

Returns a JSON object indicating whether prompt injection or jailbreak content was detected in the input, along with sanitized text that has been stripped of adversarial instructions, enabling safe downstream use by the agent.

## 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/domain-osint-agentdiet-dev-a2a-indirect-prompt-injection-jailbreak-923e1adc/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from domain-osint.agentdiet.dev](https://www.zero.xyz/host/domain-osint.agentdiet.dev/llms.txt)