An AI-powered Campaign Copilot for Foundry Virtual Tabletop that helps Game Masters manage their campaigns through natural language conversation.

Simulacrum is an intelligent agent that lives inside your Foundry VTT sidebar. Unlike simple text generators, Simulacrum is a Campaign Copilot—it can understand your requests, plan multi-step operations, and directly interact with your game world.

Ask it to:

• Create NPCs, items, journal entries, and other documents
• Search and read existing campaign content
• Update documents with new information
• Execute complex multi-step tasks
• Run custom macros and JavaScript automation

Simulacrum understands Foundry VTT's document structure. Create an actor, and it knows about abilities, items, and system-specific fields. Ask for a magic sword, and it builds one with proper stats.

The AI uses a set of tools to interact with your world:

• Document Tools: Create, read, update, delete, search, and list documents
• Compendium Tools: Lock/unlock packs, manage document ownership
• Asset Search: Find images, audio, and other assets in your data
• Schema Introspection: Understands your game system's data structures
• Macro Execution: Run any macro in your world
• JavaScript Execution: Advanced automation capabilities

Destructive operations (update, delete, macro/JS execution) require confirmation before executing. Configure per-tool permissions with Allow, Deny, Always Allow, or Blacklist options.

For complex operations, Simulacrum can create and manage tasks, tracking progress across multiple steps and reporting when complete.

Connect to the AI provider of your choice:

• OpenAI (GPT-4, etc.)
• Google Gemini
• Anthropic Claude
• Any OpenAI-compatible API (local models, proxies, etc.)

Simulacrum is restricted to Game Masters only—players cannot access the AI interface or execute commands.

1. Open Foundry VTT and navigate to Add-on Modules
2. Click Install Module
3. Search for "Simulacrum"
4. Click Install

1. Download the latest release from GitHub Releases
2. Extract to your Data/modules/ directory
3. Restart Foundry VTT

1. Enable the module in your world
2. Open Module Settings → Simulacrum
3. Configure your AI provider and API key
4. Access Simulacrum from the sidebar tab

• API Provider: Select your AI service
• API Key: Your provider's API key
• Model: The model to use (e.g., gpt-4o, gemini-2.5-flash, claude-3.5-sonnet)

Click the Simulacrum tab in the sidebar and start chatting. Examples:

"Create a goblin warrior named Grunk with 15 HP and a rusty shortsword"

"Find all journal entries about the Kingdom of Eldoria"

"Update the Dragon's Lair scene to add a treasure hoard in the corner"

"Create a task to build out the entire merchant guild, including 5 NPCs and their shop inventory"

Create macros that Simulacrum can execute as tools. Define a tool constant in your macro with name, description, and parameters schema.

For advanced users, Simulacrum can execute arbitrary JavaScript, enabling complex automation workflows.

• Foundry VTT v13.0.0 or higher

• An AI provider API key with tool/function calling support:

  • OpenAI (GPT-4, GPT-4o, etc.)
  • Google Gemini (2.0 Flash, 2.5 Pro, etc.)
  • Anthropic Claude (3.5 Sonnet, etc.)
  • Any OpenAI-compatible API that supports function calling

Note: Your AI endpoint must support OpenAI-style tool/function calling. Simulacrum relies on native tool calling to execute actions reliably. Endpoints that only support text completion are not compatible.

• Issues: GitHub Issues
• Source: GitHub Repository
• Donate: Buy Me a Coffee

MIT License - see LICENSE for details.