Setup Guide

This guide walks you through connecting Tailscale Aperture to Highflame for evaluating every captured prompt and tool call.

Prerequisites

• A Tailscale tailnet with Aperture deployed and configured with at least one LLM provider

• A Highflame account with an active project

• A Highflame API key (format: hf_sk-...) available to configure the Aperture hook

• Access to the Aperture settings UI at http://ai/ui/

1

Generate a Highflame API key

1. Log in/Sign Up to the Highflame Platform.

2. Navigate to Agent Control Plane > Agents

3. Register your agent

4. An API key will be generated (starts with hf_sk-).

Keep the key secure. Paste it into the Aperture hook configuration.

2

Configure the Highflame hook endpoint

In Aperture settings, add a highflame hook under hooks:

{
  "hooks": {
    "highflame": {
      "url": "https://api.highflame.ai/v1/agent/events",
      "apikey": "hf_sk-YOUR_API_KEY_HERE",
      "timeout": "30s"
    }
  }
}

Field	Description
url	Highflame endpoint to ingest Aperture agent events (POST /v1/agent/events)
apikey	Your Highflame API key. Aperture sends this to Highflame as Authorization: Bearer <key>.
timeout	How long Aperture waits before timing out the hook request

3

Configure the hook grant (what Aperture sends)

Add a grant in your Aperture config so the hook fires when tool calls occur, and so Highflame receives the fields it needs to evaluate.

Use a grant that matches tool_call_entire_request and includes these fields:

• user_message

• tools

• request_body

• response_body

• raw_responses

Note: In the hook payload, Highflame expects the JSON key tool_calls. When you select fields: ["tools"] in Aperture, Aperture provides the corresponding tool calls under tool_calls for Highflame to parse.

Example grant (adjust src/scope as needed):

{
  "temp_grants": [
    {
      "src": ["*"],
      "grants": [
        {
          "hook": {
            "match": {
              "providers": ["*"],
              "models": ["*"],
              "events": ["tool_call_entire_request"]
            },
            "hook": "highflame",
            "fields": [
              "user_message",
              "tools",
              "request_body",
              "response_body",
              "raw_responses"
            ]
          }
        }
      ]
    }
  ]
}

If you want to limit who/what triggers evaluation, narrow src, providers, or models instead of using ["*"].

4

Save and verify

1. Save your Aperture configuration.

2. Use any LLM client through your Aperture proxy that triggers tool calls.

3. In Highflame, confirm that detections/policy decisions show up for the corresponding session.

Note: The POST /v1/agent/events endpoint acknowledges immediately. If you have configured everything correctly, you should see evaluation results appear shortly in the dashboard.