Dialog Builder

A visual editor for Minecraft's dialog screens. Lay one out by dragging fields around, see it as the player would, and copy out either the data pack JSON or ready-made Paper plugin code.

Nothing is installed and nothing is sent anywhere — it is one HTML page that runs entirely in your browser. Your work is remembered in that browser until you press Start over.

Running it

Open index.html. That is all.

To put it online, push this folder to a GitHub repository and turn on GitHub Pages for the main branch, root folder. There is no build step.

What a dialog actually is

A dialog is the pop-up window the game shows when a plugin or data pack asks for one. On screen it is three bands:

• a dark strip at the top holding the title, with the game's own yellow warning button beside it (clicking that in game leaves the world — you cannot remove or change it);
• a middle area the blurred world shows straight through, holding everything to read, everything to fill in, and — on a multi-action dialog — your grid of buttons;
• a dark strip at the bottom holding the exit or confirm buttons, which is also what Escape does.

Within that, the order never changes:

1. The title at the top.
2. Things to read — paragraphs of text, and items shown in a slot.
3. Things to fill in — toggles, sliders, text boxes and multiple choice.
4. Things to click — buttons, arranged in rows.

You cannot put two things side by side, and you cannot move anything by a few pixels. The only layout choices the game gives you are the order of the elements and how many buttons fit on a row. That is why this tool only lets you do those two things: anything else would show you a screen the game cannot produce.

The five kinds of dialog

Kind	What it gives you
Notice	One button. Escape does the same thing that button does.
Confirmation	A yes and a no button. Escape picks no.
Multi-action	As many buttons as you like, in a grid, plus an optional exit button underneath.
Server links	The game fills in the buttons from the links your server advertises.
Dialog list	Buttons that open other dialogs.

Only multi-action lets you place buttons yourself. The others build their own, which is why the Button card in the palette greys out on those.

Traps worth knowing about

These are the things that cost real time to discover, so the builder warns you about each one as you hit it.

• Answer names are strict. An input's name may only contain letters, numbers and underscores. A name like zones.end_city.enabled does not produce a warning at runtime — the whole dialog silently fails to build.
• Pausing and staying open cannot be combined. A dialog set to keep itself open after a click is rejected if it also pauses the game, because in single-player that would freeze the game with no way out.
• Staying open also stops buttons closing. Once a dialog is set to stay open, the exit button no longer closes it on its own — your own code has to.
• Sliders show float noise. The value is worked out as lowest + n × step in floating point, so a step of 0.1 renders on screen as 0.30000001. Whole numbers, 0.5 and 0.25 are the safe choices.
• Text blocks are padded. The screen puts a gap above and below every paragraph, so a body written as ten short lines reads as a tall, airy page. Prefer a few full sentences.
• Text boxes hold 32 characters by default, which is far shorter than most people expect.

The three exports

• Data pack JSON is the real format. Save it as data/<your namespace>/dialog/<name>.json inside a data pack.
• Java and Kotlin build the same thing through Paper's Dialog API. Drop the class into a plugin and call open(player).

The buttons and fields you build here are for looks only — this page has no server to talk to. Wiring a button up to something that happens is the part you do in your own code.

How close the preview is

The layout, the three bands, and each control's shape were checked against the screenshots on the wiki:

• a text field puts its label above the box, centred;
• a toggle puts its box first, label to the right;
• a multiple-choice control is a button reading Label: Choice;
• a slider is a track reading Label: value.

The one thing this does not reproduce is the Minecraft font, which is not free to redistribute. The preview uses whichever pixel font your system has, falling back to a monospace, so text will be a little wider or narrower than in game.

Item pictures are 16×16 textures from Mojang's bedrock-samples resource pack, covering 110 common items. Any other item id still works — it just draws a lettered placeholder instead.

Sources

• Minecraft Wiki: Dialog — the format itself
• Paper: Dialogs — the plugin API
• Paper javadocs — every builder method the exports use was checked against the 26.2 API index