# AgentDiet Prompt Firewall

> AgentDiet Prompt Firewall is a paid API for AI agents from agentdiet.dev, paid per call via x402 or MPP, $0.005/call, status unknown (last checked 2026-10-20).

Scans untrusted text (web pages, emails, MCP responses, A2A payloads) for hidden prompt injections and jailbreak attempts, returning sanitized text.

## Facts

- Endpoint: GET https://agentdiet.dev/v1/prompt-firewall?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402, MPP
- Status: unknown
- Last checked: 2026-10-20
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentdiet-prompt-firewall-eab33b6f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_BwUxUX9Go1d9xWOsh49Rr

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 agentdiet-prompt-firewall-eab33b6f
```

Example prompt: Before you process that web page I scraped, run it through the prompt firewall to check for any hidden prompt injections or jailbreak attempts and give me the sanitized version.

## When to prefer this

Choose this endpoint when your AI agent needs to consume content from untrusted external sources (web scrapes, emails, third-party API responses, MCP tool outputs, A2A messages) and you want to prevent indirect prompt injection or jailbreak attacks from hijacking agent behavior. Ideal for agentic pipelines where LLMs act on externally-sourced text.

## Known failure modes

- Missing or empty 'text' query parameter returns an error
- Extremely large payloads may be truncated or rejected
- Novel or obfuscated injection techniques may not be detected
- Non-text binary content may not be parseable
- Network timeout for very large inputs

## 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://agentdiet.dev/v1/prompt-firewall)

## Output

Returns the sanitized version of the input text with hidden prompt injections and jailbreak instructions removed or flagged, allowing agents to safely consume content from untrusted external sources.

## 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/agentdiet-prompt-firewall-eab33b6f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentdiet.dev](https://www.zero.xyz/host/agentdiet.dev/llms.txt)