PUBLIC BETA · v0.1.0

An AI agent that can play your game.

BIGGI works beyond the codebase. It opens the engine, reads the console, inspects scenes, repairs what broke, and runs the game again until there is evidence. Connect your own provider key locally to start; managed BIGGI models are coming later.

Install from your terminalv0.1.0

macOS / Linux

> curl -fsSL https://biggi.dev/install.sh | sh

Windows PowerShell

> irm https://biggi.dev/install.ps1 | iex

Detects your platform, downloads the matching VSIX, and installs it with the VS Code CLI. Download manually

Explore the Game Loop View source

Unity 2021.3 → Unity 6Godot 4.xBrowser Phaser · Three.js + moreMIT open source

One continuous loop · VS Code

From prompt to proof, without the copy-paste ritual.

01Detect

It knows the project before you explain it.

Engine, version, language, project root, and engine-specific rules are loaded into every task. Fresh folder? BIGGI can scaffold the project first.

UnityGodotUnrealBevyWeb

02Connect

It crosses into the running engine.

A warm Unity editor bridge, deterministic Godot runner, or managed browser session gives the agent real compile status, console output, scene state, tests, screenshots, and profiler data.

Runs the scene and reads structured errors
Queries static or live runtime trees
Stops cleanly when the task or session ends

03Diagnose

It follows the bug into the scene.

A stack trace is only half the story. BIGGI maps failures back to the exact node, GameObject, framework object, prefab, missing resource, shader, or unassigned field. In Unity and Godot it can repair structured scene data without blind text edits.

NullReferenceExceptionSpawner.enemyPrefab is unassigned in Level2.unity

04Prove

It plays the result, then shows its work.

Replay input, invoke explicit game actions, watch semantic state across frames, guard invariants, and carry the same tracked scenario into CI. Success means a passing run with evidence, not a confident paragraph.

contract actionsinvariant guardswatch timelines

The marquee loop

The bug is in your scene, not your code.

BIGGI reads the exception, finds the component, inspects the loaded scene, wires the missing reference through Unity's serialization APIs, and replays the failing scenario.

One loop. Five engine-aware tools. A result you can review.

BIGGI Game Loop — Dread Crown playtest

Deep where it matters

Built with the engines, not pasted on top.

Capabilities are explicit. BIGGI tells you what it can verify in the current project.

Unity Game Loop

The running editor is the fast path.

Compile autopilot, console and play-mode control, safe scene and prefab edits, project-owned state, action, and invariant contracts, Animator/NavMesh/physics observation, EditMode/PlayMode tests, percentile profiling, and scenario replay.

2021.3 LTS → Unity 6

Godot Game Loop

Headless verification that understands scenes.

Runs, structured console parsing, GUT and gdUnit results, .tscn-safe scene edits, live tree queries, screenshots, profiling, scripted input, and scene-aware root causes.

Godot 4.x · GDScript

Browser Game Loop

A managed browser session becomes the playtest rig.

Managed dev servers and browser pages, combined browser/server/network/shader errors, framework-aware live trees, safe build-gated asset moves, semantic runtime contracts, seeded input replay, screenshots, video, traces, percentile profiling, and production-preview verification.

Phaser · Three.js · Babylon.js · PixiJS

Common Browser Game Loop: custom Canvas/WebGL, Excalibur, Kaplay, and Matter.js. Detection and engine-aware context: Unreal, Bevy, MonoGame, and LÖVE.

One editor. Several safe agents.

Keep the conversation, the game, and every diff together.

01 / GAME LOOP

Run the game from the conversation.

Chat, engine tools, permissions, snapshots, and reviewable evidence stay beside the code that produced them.

Explore the VS Code extension →

EnemySpawner.cs — DungeonCrawl

12public class EnemySpawner : MonoBehaviour
13{
14    [SerializeField] private Enemy enemyPrefab;
15    [SerializeField] private Transform[] points;
16
17    public void SpawnWave()
18    {
19        foreach (var point in points)
20            Instantiate(enemyPrefab, point.position, point.rotation);
21    }
22}

BIGGI — /gameplayUnity 6 · C#

the second enemy wave never appears

The script is fine. enemyPrefab was unassigned on Spawner in Level2.

✓ game_scene_edit · wired▸

✓ game_playtest · passed▸

verified · frame 612

Ask BIGGI…

02 / AGENT MANAGER

Run several ideas without tangling your branch.

Parallel sessions live in isolated git worktrees so you can compare implementations, models, and live diffs before choosing what to keep.

Explore Agent Manager →

Agents

Games are systems in motion, not folders full of code.

Read why we're building BIGGI →

Field manual

The useful questions.

What makes BIGGI different from a general coding agent?

BIGGI can cross the boundary between source code and the running game. In supported Unity, Godot, and browser projects it can run the engine or managed browser, inspect scene and runtime state, test, profile, capture screenshots, and replay gameplay before it claims a change works. Unity and browser projects can also expose bounded state, invariants, and explicit actions so the agent works with project-owned meaning instead of guessing at arbitrary runtime fields.

Which engines have the full Game Loop?

Unity 2021.3 LTS through Unity 6, Godot 4.x, Phaser, Three.js, Babylon.js, and PixiJS have deep Game Loop adapters today. Custom Canvas/WebGL, Excalibur, Kaplay, and Matter.js share the common Browser Game Loop. Unreal, Bevy, MonoGame, and LÖVE receive automatic detection, engine context, and specialized agents without pretending every runtime capability exists everywhere.

Does it work without a BIGGI account?

Yes. The VS Code extension is MIT licensed. Bring an API key for your preferred provider, use provider-native login, or connect a local model. Managed BIGGI gateway access is coming later.

Can it create a game project from an empty folder?

Yes. game_new can scaffold a ready-to-run Unity, Godot, or TypeScript/Vite browser project, detect projects one folder below the workspace, and hand the new project directly to the Game Loop. Browser templates include Phaser, Three.js, Babylon.js, PixiJS, and Canvas.

Can I use the same playtests in CI?

Yes. Scenarios can live in .biggi/playtests and run through the Unity editor bridge or batch mode, headless Godot, or managed Chromium, Firefox, and WebKit sessions. Results include stable exit codes, JSON, JUnit, screenshots, and replay evidence.