> ## Documentation Index
> Fetch the complete documentation index at: https://openrouter.ai/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Raindrop

> Send traces to Raindrop

[Raindrop](https://raindrop.ai) is an AI observability platform for monitoring and evaluating LLM applications. With Raindrop, you can track conversations, analyze model performance, and debug AI workflows.

## Step 1: Get your Raindrop write key

In Raindrop, navigate to your project settings:

1. Log in to your [Raindrop](https://raindrop.ai) account
2. Go to **Settings** and find your project's **Write Key**
3. Copy the write key

## Step 2: Enable Broadcast in OpenRouter

Go to [Settings > Observability](https://openrouter.ai/settings/observability) and toggle **Enable Broadcast**.

<img src="https://mintcdn.com/openrouter-d02e98a0/PSwwwiCqAD_BNeni/assets/guides/features/broadcast/arize/broadcast-enable.png?fit=max&auto=format&n=PSwwwiCqAD_BNeni&q=85&s=a48ecd5df85b4e6f3982c8402671f631" alt="Enable Broadcast" width="2692" height="1296" data-path="assets/guides/features/broadcast/arize/broadcast-enable.png" />

## Step 3: Configure Raindrop

Click the edit icon next to **Raindrop** and enter:

* **Write Key**: Your Raindrop project write key
* **Base URL** (optional): Default is `https://api.raindrop.ai`. Change only if using a custom endpoint

## Step 4: Test and save

Click **Test Connection** to verify the setup. The configuration only saves if the test passes.

## Step 5: Send a test trace

Make an API request through OpenRouter and view the event in your Raindrop dashboard under **Events**.

<img src="https://mintcdn.com/openrouter-d02e98a0/vKv_Fe97IEm3a1mW/assets/guides/features/broadcast/broadcast-raindrop-trace.png?fit=max&auto=format&n=vKv_Fe97IEm3a1mW&q=85&s=d85967fd883ab6dd038def008fc099b8" alt="Raindrop Event View" width="3176" height="1994" data-path="assets/guides/features/broadcast/broadcast-raindrop-trace.png" />

Each event includes:

* **User Input**: The latest user message from the conversation
* **Assistant Output**: The model's completion text
* **Properties**: Token counts, cost, latency, model, provider, and finish reason

## Custom Metadata

Raindrop receives events with custom metadata included as event properties. Use the `trace` field to attach additional context to your events.

### Supported Metadata Keys

| Key          | Raindrop Property | Description                                         |
| ------------ | ----------------- | --------------------------------------------------- |
| `trace_id`   | `trace_id`        | Custom trace identifier for grouping related events |
| `trace_name` | `trace_name`      | Name displayed as the event's trace name            |

### Example

```json lines theme={null}
{
  "model": "anthropic/claude-sonnet-4",
  "messages": [{ "role": "user", "content": "What time is it?" }],
  "user": "user_35",
  "session_id": "session_abc",
  "trace": {
    "trace_name": "Time Check",
    "feature": "assistant"
  }
}
```

Every key inside `trace` that is not in the table above is forwarded as-is (e.g. `feature` becomes the property `feature`).

### Additional Context

* The `user` field maps to Raindrop's `user_id` for user-level analytics
* The `session_id` field maps to `convo_id` for grouping conversation turns
* Events include system properties like `model`, `provider`, `total_cost`, `prompt_tokens`, `completion_tokens`, `duration_ms`, and `finish_reason`

## Privacy Mode

When [Privacy Mode](/docs/guides/features/broadcast#privacy-mode) is enabled for this destination, the `input` and `output` fields are excluded from events. All other event data — token usage, costs, timing, model information, and custom metadata — is still sent normally. See [Privacy Mode](/docs/guides/features/broadcast#privacy-mode) for details.