Your story is a world.
Give it architecture.

Plotheus is a context orchestration platform for writers. Define your story world as structured data. Let AI write with perfect knowledge of who, where, when, and why. Without hallucinating the rest.

See How It Works

The Problem

AI can write prose. It can't remember your story.

Every AI writing tool has the same flaw: context collapse. You paste your manuscript into a chat window, blow past the context limit by chapter three, and the model starts hallucinating characters, forgetting timelines, and contradicting its own continuity.

The problem isn't the model. It's what you feed it. A 200,000-word novel dumped into a prompt is noise. What an AI actually needs to write Chapter 12 is the resolved state of the world at Chapter 12: who trusts whom, which places matter, what just happened, and nothing else.

That's what Plotheus builds. Not another writing assistant. A story architecture layer that gives any AI agent exactly the context it needs: precise, minimal, temporally resolved. So the prose comes out right the first time.

Core Concepts

A living world that evolves with every chapter

Structured World Building
Define your own building blocks: characters, places, factions, magic systems, anything. Give each one detailed fields. Your story world becomes organized, searchable data instead of scattered notes.
Living Connections
Connections between characters, places, and events are more than simple links. They carry meaning. Lena "trusts" Kai in Chapter 3, "distrusts" him by Chapter 7. Plotheus tracks every shift.
Story Memory Over Time
Relationships carry forward through your chapters automatically. When you ask for the state of things at Chapter 12, you get everything that's happened: new connections, changed loyalties, and inherited continuity.
Context Assembly
Build precise context packages for your AI. Pick the characters, places, and events that matter for a scene. Combine them, exclude what's irrelevant, preview exactly what the AI will know, and send.

How It Works

From blank page to structured world in minutes

1
Create a story workspace
Choose a template (Book, Web Novel, Screenplay, Short Story) that pre-configures your building blocks, fields, and structural hierarchy. Or start blank and define everything yourself.
2
Build your world
Define your world's building blocks (characters, places, factions, items) with detailed fields: descriptions, traits, numbers, choices, and links between them. Each type gets a color. Each field has a purpose.
3
Populate and connect
Create instances and connect them with meaningful, evolving relationships. "Lena trusts Kai" in Chapter 3. "Kai controls the capital" from Chapter 5 onward. Your world grows richer with every chapter.
4
Assemble context, not prompts
When you're ready to write Chapter 12, pick your target section, select the characters and events that matter, and Plotheus assembles everything the AI needs to know at that moment: who's involved, what's changed, what just happened.
5
Send to any AI agent
Copy the context to ChatGPT, connect through MCP, call the REST API, or load a custom skill. Plotheus serves the architecture. You choose how your agent consumes it.

Connect Your Way

Multiple paths to your story's context

Every story in Plotheus is a connectable endpoint. Whether you prefer direct API calls, protocol-level integration, or pre-built skills, your agents get the same precise, token-efficient context.

REST API

Direct and lightweight

Standard HTTP endpoints with scoped tokens. Fetch your story's context, read structure, and write prose with simple GET and POST requests. Works with any language or framework.

MCP Protocol

Agent-native discovery

Agents that support MCP can connect directly, discover available tools, and interact with your story world through a standardized protocol. Ideal for Claude Code and similar agent environments.

Skills

Pre-built instructions

Downloadable skill files that teach your AI agent how to read from Plotheus, respect your world's rules, and write in your story's voice. Drop a skill into your agent and it knows what to do.

We sell architecture, not tokens.

Plotheus never hosts or proxies LLM calls. Bring your own API keys for OpenAI, Anthropic, or any provider. You control your costs, your model choice, and your data.

Who It's For

Writers of every kind

First-time novelists
Guided templates and sensible defaults get you world-building in minutes, not hours.
Experienced authors
Full control over your world's structure, custom object types, and advanced context tools that match your existing craft.
Serial fiction writers
Speed-optimized workflows for weekly publishing. Consistency across hundreds of chapters.

Ready to architect your story?

Plotheus is building toward launch. Join the waitlist and be among the first writers to bring structure to their worlds.