add_event
Add an event to the adventure log.
LABSCO SUMMARY
It gives the model a memory the campaign can live in.
A model can already narrate a dungeon; what it cannot do is remember, three sessions later, how much gold the party has and which NPC owes them a favour. Putting characters, quests, game state and an event log behind tools means those facts survive the conversation and can be queried rather than recalled. The bulk character update is the small thing that makes combat workable — applying damage to the whole party is one call, not five.
What it is
A FastMCP server that gives a Dungeon Master — or a solo player — structured storage for a campaign. Everything hangs off one active campaign: character sheets with 5e stats, NPCs, locations, quests, combat encounters, session notes and a searchable event log, persisted to disk so a game picks up where it stopped.
What you get
- Campaigns created, listed, described and switched between, so several games can share one installation —
create_campaign,get_campaign_info,list_campaigns,load_campaign - Full 5e character sheets with ability scores and derived modifiers, hit points, armour class and inventory — created, read, updated singly or in bulk, and given items —
create_character,get_character,update_character,bulk_update_characters,add_item_to_character,list_characters - NPCs and locations created, read and listed, with the connections between them recorded —
create_npc,get_npc,list_npcs,create_location,get_location,list_locations - Quests with objectives and rewards, updated as they progress and filtered by status —
create_quest,update_quest,list_quests - Combat run turn by turn: initiative order set at the start, turns advanced, encounter closed —
start_combat,next_turn,end_combat - The party's current situation as one readable, writable state — location, session number, party level and funds, combat status, in-game date —
get_game_state,update_game_state - Session notes recorded and read back, and an adventure log of events with types, filtering and search —
add_session_note,get_sessions,add_event,get_events - Dice rolled in D&D notation such as
1d20or3d6+2, and experience distributed across an encounter —roll_dice,calculate_experience
Requirements
No account and no key — campaign data is stored locally. Python 3.12+ and uv on your PATH. The package is gamemaster-mcp (version 0.1.0), installed from a clone with uv pip install . and launched with uv run gamemaster-mcp; the client config needs the project directory as its working directory. The README supplies a system prompt for the assistant — paste it in, because it is what tells the model to keep the campaign state updated rather than only answering questions. The project describes itself as under construction.
Setup effort
Build from source — git clone https://github.com/study-flamingo/gamemaster-mcp.git
USE CASES
01
Starting a campaign from nothing
Create the campaign, build each player character with race, class and ability scores, place the opening location and the first NPC, then log the first quest.
02
Running a combat encounter
Set the initiative order, walk the turns, apply damage across the party in one call, and close the encounter when it ends.
03
Picking a game back up weeks later
Read the game state and the last session's notes to recover where the party is, what they were chasing and what they were carrying.
04
Keeping continuity across a long campaign
Log events as they happen with types and importance, then search the adventure log later for the NPC or the promise you half-remember.
05
Playing solo without a Dungeon Master
Let the model run the world from stored state — rolling dice, tracking quests and updating your sheet — rather than holding the campaign in its head.
06
Wrapping up a session
Record the notes and attendance, calculate and distribute the experience, and update the party's funds and location.
30 tools
Counted once with only startup setup. Other versions, modes or optional credentials may expose a different list.
add_item_to_character
Add an item to a character's inventory.
add_session_note
Add notes for a game session.
bulk_update_characters
Update properties for multiple characters at once by a given amount.
calculate_experience
Calculate experience points for an encounter.
create_campaign
Create a new D&D campaign.
create_character
Create a new player character.
create_location
Create a new location.
create_npc
Create a new NPC.
create_quest
Create a new quest.
end_combat
End the current combat encounter.
get_campaign_info
Get information about the current campaign.
get_character
Get detailed character information.
get_events
Get events from the adventure log.
get_game_state
Get the current game state.
get_location
Get location information.
get_npc
Get NPC information.
get_sessions
Get all session notes.
list_campaigns
List all available campaigns.
list_characters
List all characters in the current campaign.
list_locations
List all locations in the current campaign.
list_npcs
List all NPCs in the current campaign.
list_quests
List quests, optionally filtered by status.
load_campaign
Load a specific campaign.
next_turn
Advance to the next turn in combat.
roll_dice
Roll dice with D&D notation.
start_combat
Start a combat encounter.
update_character
Update a character's properties.
update_game_state
Update the current game state.
update_quest
Update quest status or complete objectives.
BEFORE YOU INSTALL
What to know first
Tools you get
30 tools when we connected.
Requires
Python 3.12+
Where it runs
The documented client runs the server on your machine.
CONTEXT COST
Moderate Standing cost
Rated by the size of the 30 tool definitions that ride along on every turn, not by how many there are
INSTALLATION
Connect your client
This one is built from source rather than installed with a single command.
Server setup
TERMINAL
git clone https://github.com/study-flamingo/gamemaster-mcp.git
cd gamemaster-mcp
uv venv
uv pip install .MCP Clients
Claude Desktop
CLAUDE DESKTOP · JSON
{
"mcpServers": {
"gamemaster-mcp": {
"command": "uv",
"args": [
"run",
"gamemaster-mcp"
],
"cwd": "<YOUR_PATH_TO_GAMEMASTER_MCP>"
}
}
}
