CrashPanel

Free · runs in your browser

The idea was yours.
The format wasn't.

Draw the logic as boxes and wires. A compiler turns your canvas into the JSON and scripts Bedrock actually accepts.

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Free account · nothing to install · the game loads the exported pack.

A live node canvas showing a three-phase boss as a finite-state machine. As its health drains past 50 percent, a condition node fires and the boss switches to phase two. A teammate cursor and an AI agent cursor are working on the same canvas.

Why a canvas

You know the moment.

The boss is finished in your head: three phases, a second form under half health, the works. Then you open the files. Component groups. Events that add and remove component groups. An animation controller in a separate file, referencing everything by string. One misplaced comma and the mob silently fails to load.

A two-phase boss, the way Bedrock wants it.

magma_golem.json 112 lines 
{  "minecraft:entity": {    "component_groups": {      "acme:base": {        "minecraft:movement": {          "value": 0.25        },        "minecraft:movement.basic": {},        "minecraft:navigation.walk": {          "can_path_over_water": true        },        "minecraft:jump.static": {},        "minecraft:behavior.nearest_attackable_target": {          "priority": 1,          "entity_types": [            {              "filters": {                "test": "is_family",                "subject": "other",                "value": "player"              },              "max_dist": 32            }          ]        },        "minecraft:behavior.move_towards_target": {          "priority": 2,          "within_radius": 32        },        "minecraft:environment_sensor": {          "triggers": [            {              "filters": {                "test": "target_distance",                "operator": "<",                "value": 3              },              "event": "acme:go_slam_attack"            }          ]        }      },      "acme:slam_attack": {        "minecraft:timer": {          "time": 1.5,          "time_down_event": {            "event": "acme:go_base"          }        }      }    },    "events": {      "acme:go_base": {        "add": {          "component_groups": [            "acme:base"          ]        },        "set_property": {          "acme:state": "base"        },        "remove": {          "component_groups": [            "acme:slam_attack"          ]        }      },      "acme:go_slam_attack": {        "add": {          "component_groups": [            "acme:slam_attack"          ]        },        "set_property": {          "acme:state": "slam_attack"        },        "remove": {          "component_groups": [            "acme:base"          ]        }      },      "minecraft:entity_spawned": {        "trigger": "acme:go_base"      }    },    "description": {      "identifier": "acme:magma_golem",      "is_spawnable": true,      "is_summonable": true,      "properties": {        "acme:state": {          "type": "enum",          "values": [            "base",            "slam_attack"          ],          "default": "base",          "client_sync": true        }      }    },    "components": {      "minecraft:health": {        "value": 400,        "max": 400      },      "minecraft:physics": {}    }  },  "format_version": "1.21.0"}

The same boss, the way you thought it.

The graph is the source of truth: the compiler writes the file on the left.

You draw the logic instead of writing it. "When HP drops below 50%, switch to phase two" is a wire between two states, in a finite-state machine you can actually see. The canvas is the add-on: a compiler turns the graph into the JSON and scripts the game accepts, with no braces to balance and no files to keep in sync by hand.

What it covers

If the game accepts it, you can draw it.

Entities and multi-phase bosses. Blocks with states and permutations. Items, recipes, loot tables. World logic and phases. Server UI forms. Multi-layer animation controllers. Even Discord slash commands, wired from the same canvas.

Multi-phase bosses

Finite-state machines you can read at a glance. A phase change is a single wire between two states.

Real-time co-editing

Build with a friend on one shared graph. Edits merge automatically, so nobody overwrites anyone's work.

Blocks, items, recipes, loot

States and permutations, crafting recipes and drop tables, drawn on the same canvas as the mob that uses them.

Server UI forms

In-game menus and forms, wired like everything else.

Discord, from the canvas

Slash commands for your server, built from the same graph.

The escape hatch

A real code editor for the edge cases, with the VS Code engine, official Mojang schemas and raw components.

3D preview

Your mob's geometry and texture, rendered in the browser before the game ever loads it.

Built for crews

One canvas, two cursors.

You and a friend on the same graph at the same time, live cursors and all, like a Google Doc that compiles. You wire the boss while your mapmaker wires the loot. Made for mapmaking teams and server crews who currently collaborate by sending each other zip files.

Bring your own AI

Your AI gets a cursor.

Your project is an MCP server. Connect the AI you already use (Claude, Cursor, Claude Code, any MCP client) and it reads and edits the same canvas with real tools instead of pasted code blobs. It even appears as a live cursor next to yours.

  • Per-agent tokens with granular permissions.
  • An approvals inbox for changes you want to review.
  • A per-node trace of everything it did.

MCP server · real read/write tools

For the edge cases

Go under the hood any time.

Some edge cases deserve raw JSON. CrashPanel ships a real code editor (the VS Code engine with official Mojang schemas) plus raw components for anything the canvas shouldn't pretend to know better. The actual files are always one click away. And you can preview your mob's geometry and texture in 3D, right in the browser, before the game ever loads it.

The output

It ends in a real file.

One click gives you a working .mcaddon that the game just loads. Running a proper toolchain? There's a Regolith filter and a CLI, so CrashPanel becomes one stage in your existing build. Design in the browser and ship the way you already do.

Export A working .mcaddon, ready for the game
Toolchain Regolith filter & CLI pipeline
Edge cases VS Code engine · official Mojang schemas
Price Free account · runs in the browser

Questions

Straight answers.

Is it free?
Signing up is free and you build in the browser. Nothing to install, no card. The pack you export is yours: drop it into the game and play.
Do I need to know how to code?
No. Logic is boxes and wires, and the compiler writes the JSON and scripts for you. If you can describe your boss's phases out loud, you can draw them. Code is there when you want it, but you never need it to start.
Can I still touch the JSON?
Yes, and in a proper editor: the VS Code engine with official Mojang schemas, plus raw components for anything the canvas doesn't cover. If you already have a build pipeline, there's a Regolith filter and a CLI, so CrashPanel slots right into it.
Why don't you sell an AI subscription?
Because you probably already pay for one. CrashPanel exposes your project over MCP, so Claude, Cursor or any MCP client works on the canvas directly, with real tools, permissions you set, an approvals inbox and per-node traces. We build the tools and you bring the model.

Draw the boss you meant to build.

Free account, in the browser. Nothing to install: the game just loads the pack.

Start building for free or join the Discord →

free · in the browser · exports .mcaddon