# Introduction

As outlined in our [open source firmware](https://github.com/usetrmnl/firmware), TRMNL exposes a GET endpoint that responds with image and other content for your device to store or render.

```
GET /api/display

# request headers example
{
  'ID' => 'XX:XX:XX:XX',
  'Access-Token' => '2r--SahjsAKCFksVcped2Q'
}

# response body example
{
  "image_url"=>"https://trmnl.s3.us-east-2.amazonaws.com/path-to-img.bmp",
  "filename"=>"2025-05-10-plugin-T00:00:00",
  "update_firmware"=>false
}
```

**With a device's API key you can request content without a TRMNL device or TRMNL firmware**.

In the following Private API docs we'll outline a few ways to take advantage of this information for your own privacy, security, and experimentation purposes.


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.trmnl.com/go/private-api/introduction.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.