Orchestrated Reality — From Role-Play to Living, Playable Game Worlds

ABSTRACT

Bridging tightly-authored narrative with deeply-simulated worlds has been prohibitively expensive. LLM-driven worlds open a new path — but today's deployed systems let the narrative voice assert state in free prose, with no validated representation of the world. We treat this as an architectural choice, not a limitation of language models: Orchestrated Reality makes the world a canonical object owned by a singleton orchestration agent, analogous to a tabletop-RPG Game Master. We formalise an LLM-driven game world for a human player as a Parameterized-Action POMDP — state is a tree of canonical JSON entities, actions decompose as a = (k, x_k), the player observes only a narrative projection o = O(s), and the transition kernel F is the LLM-driven Plan–Diff–Validate–Apply pipeline committing schema-validated, content-hashed JSON deltas — with a worked single-turn example and a catalogue of 15 incidents from a real deployment.

SYSTEM Ⅰ — THE TRANSITION KERNEL

The PDVA pipeline

The narrative never owns the world. Every turn, the orchestrator runs one transaction over canonical JSON state — story is rendered from state, not asserted into it.

01 · PLAN

Plan

The LLM interprets the player's intent (k, x_k) against the current world and proposes what should change.

→

02 · DIFF

Diff

The proposal is expressed as explicit JSON deltas against the canonical entity tree — never free prose.

→

03 · VALIDATE

Validate

Deltas are schema-validated and content-hashed; anything inconsistent with the world's rules is rejected.

→

04 · APPLY

Apply

Valid deltas commit atomically. The new state is narrated back as o = O(s).

SYSTEM Ⅱ — THE AGENT SOCIETY

The World-Agent architecture

The world is a society of independent agents connected by one harness — physical consistency in the world, cognitive consistency in every NPC. Don't code the agent; use the agent to orchestrate the world.

WORLD-AGENT

The singleton Game Master. Owns the canonical world — state, routing, narration, archive. The only agent allowed to commit deltas through PDVA.

PLACE-AGENTS

Locations with behaviour. Towns, dungeons, combat and story scenes — routed to by the world-agent as the player moves through the world.

SOUL-AGENTS

One per character, each its own mind. Private memory, secrets, and an agenda — NPCs perceive, think, and act on their own, not as lines of dialogue data.

PLAYER

You, through an avatar terminal. You see only the narrative projection o = O(s) — the world persists whether you look or not.

s ∈ 𝒮

Canonical state: a tree of schema-typed JSON entities — who is where, what has just happened, what is currently true.

a = (k, x_k)

Parameterized actions: a discrete intent kind plus structured JSON parameters.

o = O(s)

Partial observability: the player reads a narrative projection of state, never the state itself.

F = PDVA

The transition kernel is the Plan–Diff–Validate–Apply pipeline: schema-validated, content-hashed deltas.

RESEARCH SERIES

The papers behind WorldLines

PAPER Ⅰ · ARXIV 2026 · THIS PAGE