Lorewarden

A local-first toolkit for game masters of 5e-compatible tabletop RPGs: prepare your story, find the right thing at the table in one or two clicks, and react to your players.

Status: early development. Lorewarden is ready to prepare and run short adventures, but the adventure file format and the interface may still change between releases. Ideas and planned work are tracked in the issues.

Principles

• Game master first. The player side is an extra, never a requirement.
• Fast at the table. Everything in live mode is one or two clicks away.
• Local-first. Your adventures stay on your computer as JSON files. No account, no cloud; hosting it on your own server is optional.
• No autopilot. AI helps with improvisation and names; the game master decides.
• Only openly licensed content. Rules content comes from the SRD under CC BY 4.0. Anything else you type in or import yourself.

Features

Prepare

• Adventure library: create adventures, import and export them as JSON, load the example adventure.
• Scene graph editor: scenes with read-aloud text, private notes, NPCs, loot and exits. The graph shows how scenes connect and flags scenes the party cannot reach.
• Scenes at a glance: give a scene its purpose, up to three features and a way out, and live mode shows them on top so you find your footing in a second. Notes take bullet points and bold key words; read-aloud text and notes fold away.
• NPC and loot cards: write them once, give NPCs a voice note for how to play them and place them in any number of scenes.
• Clues: the truths the party should find out, as reminders for you, each with a few ways to find it (a witness, a trace, an object) tied to the scene where it turns up or the NPC who knows it. Live mode shows each way where it turns up: traces and objects under "To discover here" in the scene, what an NPC can give away on their card, each with the truth it leads to. Tick off what the party has found in either place. When the party leaves the plan, the tab "Open" lists every clue not found yet with its ways to find it and where each turns up, so you can drop a clue in wherever the party goes; the NPC tab lists the other NPCs of the adventure below those of the scene, one line each.
• Encounter generator: pick a difficulty and, if you like, a creature type, and Lorewarden puts together a fight that fits the party by the SRD 5.2 XP budget, from the SRD monsters and your own. Add it to a scene in the editor, or roll one up in live mode when the players go somewhere you did not plan for. Change the number of monsters and see right away how hard the fight is.
• Review before you play: dead ends, clues that are easy to miss or have no ways to find them, puzzles without a solution or hints, encounters whose XP no longer fit the party (SRD 5.2 budget), and boss fights without any mechanic.
• Prep sheet: the whole adventure on one page to read before the session or print: summary, the start scene, every scene in one line with its exits, clues, NPCs with their voices, fights with AC, HP and CR, and puzzles with their solutions. Open review hints are on top; from there you start a new session or continue the last one.
• Parties: keep the player characters of each group next to your own monsters: class, level, armor class, hit points, passive Perception, initiative bonus and your notes on what each player enjoys, background hooks and things to avoid. Pick the party for an adventure, and its size and level follow the characters, also after a level up; characters of different levels each count with their own level for the XP budget. Players can enter their own characters on their phones: open the sign-up for a party, they scan its QR code and enter name, class, level and numbers, if they like a backstory and goals you can weave into scenes, plus a note for you; each phone can change only what it entered, and their note stays apart from yours. Whenever you play an adventure with that party, those phones come to the table with their character on their own, without the table's code. Not a character sheet: players keep theirs in their own tools.
• Create and adapt with an AI assistant: the app copies instructions for an assistant such as Claude and imports its answer, in the language you choose. To fit an adventure to a group, pick one of your parties: its size, levels and characters come along. Duplicate the adventure for that party or have the assistant fit encounters, loot and hooks to its characters and your notes on them.

At the table

• Live mode: the current scene with its exits as buttons, loot and encounters; jump to any scene or open the scene graph. Next to the scene, a side column with tabs shows the scene's NPCs (and the others below them), the open clues, the party, the initiative, the players and the session log one at a time, so you read the scene and an NPC side by side; a click on a name at the top of the scene opens that NPC, and the initiative comes up when a fight starts.
• Battle maps: the AI assistant sketches a grid map for every scene with a fight (walls, cover, difficult terrain, where everyone starts). Live mode shows it full screen so you can copy it onto a battle mat. You can also upload your own map images.
• Rules, stat blocks, NPCs and loot on hover: in live mode and on the prep sheet, rules terms such as Prone or DC and creature names in the adventure text show the rule from the SRD 5.2.1 glossary or the creature's stat block when you point at them or tap them. Rules terms are recognised as the English rulebooks print them; for an adventure in another language, switch on English rules terms. NPCs and items are linked in the text itself, e.g. [a tall woman](npc-bertha), so even a description without a name opens the right card; the AI assistant writes these links, players only see the words, and the review flags links to deleted entries.
• Initiative tracker: rounds and turns, hit points (type +5 to heal, 5 or -5 for damage), SRD conditions; add an encounter's monsters or a scene's NPCs with one click. Monsters arrive with their hit points and roll initiative as they join, or keep the initiative score from the stat block if you turn the rolls off. Groups of monsters roll their hit points from the hit dice, so they differ; a single monster keeps the average. "Add the party" puts all characters in with their armor class, and with their hit points if you track them (a setting; otherwise mark a character as down with Unconscious). Player characters stay for the whole session. When combat starts, players enter their initiative on their phones and it is sorted in right away; you see who is still missing.
• NPCs who fight: an NPC can point to the creature in the monster pool with their stat block. The NPC card then shows armor class, hit points and the stat block, a mention of the creature opens the NPC card, and the NPC joins the initiative with those hit points. The AI assistant sets this for NPCs who may fight.
• Individual monsters and boss mechanics: give monsters of an encounter a name, a few words to narrate and their own hit points, e.g. a goblin leader next to three goblins. Boss fights and climaxes get mechanics such as phases, a countdown or crystals that shield the boss: the initiative tracker reminds you when a trigger fires, and destructible objects join it without a turn. The AI assistant writes both where they add something.
• Level up: mark the scene after which the party gains a level, usually the climax. Live mode reminds you when you reach it, and the prep sheet shows it in the list of scenes. The AI assistant suggests one when it writes an adventure.
• Session log: scene changes are logged automatically, add notes in one line, export the log as Markdown.

Players

• Players at the table: players join with their phones by scanning a QR code; no app and no account needed. When the adventure is played with a party, each player picks their character when joining, so their initiative lands on the right character. Show handouts, images, read-aloud text and hints to everyone or to single players, and take them back. Phones need to be in the same Wi-Fi as the game master's computer.
• Puzzles: riddles, locks and other puzzles with a picture or SVG drawing, a solution and hints from a gentle nudge to almost the answer. In live mode, show the puzzle on the players' phones and send each hint to everyone or to single players, e.g. one fragment per player. The AI assistant builds puzzles into new adventures and can draw them as SVG.

Monsters

• Monster stat blocks: all 331 monsters of the SRD 5.2.1 are built in. The AI assistant picks its creatures from them, and live mode and the initiative tracker show the full stat block with one click. Rules text stays in English.
• Your own monsters: create monsters with a full stat block, copy an SRD monster and change it, or let an AI assistant write one. They are kept next to the SRD monsters, every adventure can use them, and the AI assistant knows them. Creatures an AI invents for an adventure get a full stat block too; save them to your monsters with one click. An exported adventure carries the stat blocks it needs.

The app is in English and German, and follows your system's light or dark mode.

Not planned: character sheets and dice rollers (players keep using their own tools, e.g. D&D Beyond), map editors, a complete virtual tabletop and rules automation. Ideas for what comes next, such as a display for a TV or projector at the table, are collected in the issues.

Getting started

You need Node.js 22 or newer.

git clone https://github.com/mLampir/lorewarden.git
cd lorewarden
corepack enable
pnpm install
pnpm start

Then open http://localhost:47616. To try it out, load the example adventure from the library.

A small Lorewarden server runs on your computer. It keeps every adventure as a file in the folder ~/Lorewarden (change it with --dir or LOREWARDEN_DIR) and your own monsters in monsters.json there, serves the game master app to this computer only, and passes on to the phones what you show your players. Back up the folder, or export single adventures to share them.

To show handouts on your players' phones, open live mode and press Connect phones. The phones scan the QR code and need to be in the same Wi-Fi. Your operating system may ask whether Node.js may accept connections; allow it for private networks.

To update, run git pull, pnpm install and pnpm start again.

Hosting it on a server

To run Lorewarden on your own server with Docker, behind a password and HTTPS, see Hosting Lorewarden yourself. The game master app shows when a new release is out; with the optional updater container, it updates itself at the press of a button or at night, with a backup and a way back.

Work with an AI assistant (MCP server)

Lorewarden comes with an MCP server, so an AI assistant such as Claude Desktop can work on your adventures with you, using your own subscription:

• Build an adventure: the prompt "New adventure" works through a short adventure with you step by step and saves every step. Bring as much as you already have, such as a plot, NPCs or monsters that should appear; Claude builds on it and skips what you have settled.
• Fit an adventure to your party: the prompt "Adapt an adventure" rates the encounters for a new party size or level, works in the characters once you know them, tells you what it would change and saves only what you agree to.
• Change an adventure: "Make the cellar creepier", "Add a second way into the tower".
• At the table: the prompt "What now?" knows the scene you are playing, the session log and the running combat, and suggests three ways to react.
• Monsters: the assistant picks SRD monsters and your own monsters that fit your party, and writes a full stat block for a creature it invents, so you have every stat block at the table. Ask it to save a monster to your monsters, and every adventure can use it.

The assistant uses the same Lorewarden server as the app, so everything it changes appears in the app right away. Your adventures stay on your computer; the assistant only sends its provider what it reads while it works with you.

If you host Lorewarden on a server, you can skip the setup below and add it in Claude as a custom connector instead, see AI assistants.

Set it up

1. In your copy of Lorewarden (see Getting started), build the MCP server:

   pnpm build:mcp

2. In Claude Desktop open Settings → Developer → Edit Config and add Lorewarden to claude_desktop_config.json, with the full path to your copy:

   {
     "mcpServers": {
       "lorewarden": {
         "command": "node",
         "args": ["/path/to/lorewarden/packages/mcp/dist/lorewarden-mcp.js"]
       }
     }
   }

3. Restart Claude Desktop and start Lorewarden with pnpm start. The AI works on the same adventures as the app, and its changes show up in the open app right away. When Lorewarden is not running, it works on the adventure files directly.

Update it

In your copy of the repository:

git pull
pnpm install
pnpm build:mcp

Then quit and restart Claude Desktop, so it starts the new MCP server, and restart Lorewarden. The configuration stays as it is.

More options, such as another folder, and the list of tools are in the server's README.

Repository layout

apps/
  dm/          Game master web app (laptop/tablet)
  player/      Player web app (phone)
packages/
  content/     Openly licensed game content: the SRD 5.2.1 monsters and rules glossary
  core/        Data model, validation and rules math (plain TypeScript, no UI)
  mcp/         MCP server for AI assistants such as Claude Desktop
  server/      Lorewarden server: keeps adventures, serves both apps, talks to the phones
  updater/     Optional container that updates a self-hosted Lorewarden, with a backup
docs/          Hosting guide and design guidelines
examples/      Example adventures written for this project

Development

Requirements: Node.js 22 or newer and pnpm (corepack enable installs the right version).

pnpm install
pnpm start        # build everything and run Lorewarden on http://localhost:47616
pnpm dev          # Lorewarden server (with a fresh player build) plus the game master app with hot reload on http://localhost:5173
pnpm dev:player   # player app with hot reload on http://localhost:5174/play/
pnpm test
pnpm lint
pnpm typecheck
pnpm check:privacy  # looks for local paths and email addresses in tracked files
pnpm build

See CONTRIBUTING.md before opening a pull request.

License

Copyright (C) 2026 Lampir (https://lampir.at)

• Code: GNU Affero General Public License, version 3 or (at your option) any later version, see LICENSE. If you run a modified version as a service for others, you must offer them its source code. The project comes without any warranty.
• Example adventures in examples/: CC BY 4.0.
• Rules content: This work includes material from the System Reference Document 5.2.1 ("SRD 5.2.1") by Wizards of the Coast LLC, available at https://www.dndbeyond.com/srd. The SRD 5.2.1 is licensed under the Creative Commons Attribution 4.0 International License, available at https://creativecommons.org/licenses/by/4.0/legalcode. The monster stat blocks in packages/content were converted from the SRD 5.2 data of the Open5e project, and the rules glossary from the Markdown version of the dnd-5e-srd-markdown project, see packages/content/LICENSE.md.
• Adventure-building advice in the instructions for AI assistants: this work includes material taken from the Lazy GM's Resource Document by Michael E. Shea of SlyFlourish.com, available under a Creative Commons Attribution 4.0 International License.
• Icons from Lucide under the ISC License, see THIRD-PARTY-NOTICES.md.

Much of the code is created with Claude.

Lorewarden is unofficial fan content and is not affiliated with, endorsed, sponsored or approved by Wizards of the Coast.