Open-Sourcing Our Game AI Stack
At Vantage Digital Labs, we've been building AI-powered NPC dialogue systems for games. Most of our internal tooling is now stable enough to share. We're releasing everything as open source — SDKs, starter templates, and CLI debugging tools.
Here's what's in each repo and how to get started.
The Repos
We maintain code across two GitHub accounts:
Organization (vantage-digital-labs) — Production SDKs:
-
core-sdk— Node.js / Browser SDK -
unity-sdk— Unity C# SDK -
unreal-plugin— Unreal Engine 5 C++ plugin
Personal (maximilian32541-spec) — Developer tools:
-
npc-dialogue-starter— Template project -
game-ai-utils— CLI debugging tools
core-sdk — The Foundation
The core SDK is a TypeScript client that talks to our inference API. It handles NPC chat, streaming responses, voice synthesis, and session memory.
const { VantageClient } = require('@vantage-labs/core-sdk');
const client = new VantageClient({
apiKey: 'vk_live_your_key_here',
region: 'asia-northeast1'
});
// Basic NPC chat
const response = await client.npc.chat({
npcId: 'npc_blacksmith_01',
playerId: 'player_abc',
message: 'Can you repair my sword?',
context: {
playerGold: 150,
reputation: 'friendly',
timeOfDay: 'evening'
}
});
console.log(response.dialogue); // "Aye, I can fix that. 50 gold."
console.log(response.emotion); // "helpful"
For real-time dialogue, use WebSocket streaming:
const ws = client.npc.stream({
npcId: 'npc_guard_01',
playerId: 'player_abc'
});
ws.on('dialogue_chunk', (chunk) => {
process.stdout.write(chunk.text); // Display as it generates
});
ws.on('emotion_shift', (state) => {
// state.sentiment, state.trust, state.alertLevel
updateCharacterAnimation(state);
});
ws.send({ message: 'I need to pass through here.' });
unity-sdk — For Unity Developers
The Unity SDK wraps the core API with MonoBehaviour components. Drop NPCDialogueController onto any GameObject, assign an NPC profile, and you're running.
using VantageSDK;
public class MerchantBehavior : MonoBehaviour
{
private NPCDialogueController dialogue;
void Start()
{
dialogue = GetComponent<NPCDialogueController>();
dialogue.OnResponse += HandleResponse;
}
public void GreetPlayer(string playerId)
{
dialogue.SendMessage("Welcome! Looking for something special?", playerId);
}
void HandleResponse(DialogueResponse response)
{
Debug.Log($"{response.Text} [{response.Emotion}]");
animator.SetTrigger(response.Emotion);
}
}
unreal-plugin — For Unreal Engine 5
The Unreal plugin is a C++ module with Blueprint-exposed nodes. It supports both REST and WebSocket connections, with async Latent Actions for non-blocking inference calls.
void AMyNPC::OnPlayerInteract(FString PlayerId, FString Message)
{
UVantageNPCComponent* Vantage = FindComponentByClass<UVantageNPCComponent>();
FVantageChatRequest Request;
Request.NpcId = NPCId;
Request.PlayerId = PlayerId;
Request.Message = Message;
Vantage->Chat(Request, FOnVantageResponse::CreateUObject(
this, &AMyNPC::HandleDialogueResponse
));
}
void AMyNPC::HandleDialogueResponse(const FVantageChatResponse& Response)
{
SpeechBubble->SetText(FText::FromString(Response.Dialogue));
PlayEmotionAnimation(Response.Emotion);
}
npc-dialogue-starter — Build Your Own
This is a standalone template for building NPC dialogue without our API. It works with any OpenAI-compatible endpoint (OpenAI, DeepSeek, Ollama, vLLM).
git clone https://github.com/maximilian32541-spec/npc-dialogue-starter
cd npc-dialogue-starter
npm install
cp .env.example .env # Add your API key
node index.js
The architecture:
Player Input → Context Builder → LLM API → Response Parser → Game Engine
↑ |
└──── Memory / State ──────────┘
Four core modules:
| Module | What it does |
|---|---|
DialogueManager |
Session history, message routing |
ContextBuilder |
NPC personality + world state injection |
MemoryStore |
Long-term memory with relevance scoring |
EmotionSystem |
Emotion-aware prompt modification |
game-ai-utils — Debugging Tools
Three CLI tools for testing NPC behavior during development:
npc-bench — Benchmark response quality and latency:
node npc-bench.js --npc merchant --iterations 10 --concurrent 3
dialogue-replay — Replay saved conversations:
node dialogue-replay.js --file conversations/sample-merchant.json
prompt-lab — Interactive prompt testing:
node prompt-lab.js --npc=guard
Why Open Source?
Game AI is moving fast. Studios shouldn't have to rebuild basic infrastructure from scratch. By open-sourcing our tooling, we hope to:
- Lower the barrier — Anyone can prototype NPC dialogue in an afternoon
- Get feedback — Real game devs will find bugs and edge cases we miss
- Build community — The best ideas come from people actually shipping games
Everything is MIT licensed. Use it in commercial projects, fork it, rip it apart.
What's Next
- Voice synthesis integration (TTS + emotion mapping)
- Multilingual NPC support (currently testing JP/KR/ZH)
- Pre-built NPC personality templates
Check out the repos, open issues, and let us know what you're building.
Vantage Digital Labs builds AI tooling for game teams. vantage-digital.online · GitHub
