# Running Instructions On Open Letter

When a letter is opened for the first time, you can trigger **custom instructions** to enhance gameplay and storytelling.

This is a **powerful tool** for dynamic world-building, use it to:

* Start a quest when the player reads a letter (e.g., “Find and locate Mr. Whiskers” 🐱)
* Unlock new areas, trigger events, or update NPC dialogue
* Reveal hidden lore through interactive letters

Since these instructions **only run the first time the letter is opened**, they ensure meaningful, one-time interactions that feel immersive and intentional.

<figure><img src="/files/6rhqF9d8xPii5NiQFZtU" alt=""><figcaption></figcaption></figure>


---

# 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.fullscreen.no/info/game-creator-2-assets/mailbox/guides-and-demo-scene/running-instructions-on-open-letter.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.