For human DMs who already use AI
Most AI tools for D&D either replace the DM (chatbot improv that forgets your campaign) or pretend the DM doesn't exist (generic generators that ignore your canon). Grimoire, the campaign manager for TTRPG GMs, is built the other way: your AI reads your campaign as structured canon. You keep the table.
Free tier includes the AI integration. Bring your own client.
The boundary that matters
The first one makes you a better, faster, less-frustrated DM. The second one makes a worse DM than you would have been.
Most products in the "AI for D&D" space sit in the second category by default: they bundle a model, they generate content, they roleplay the world, they pretend the human at the table isn't the one making the decisions that matter. Grimoire is the other category. Your AI reads your campaign, serves your prep, drafts your recaps. You keep the table.
Three structural choices flow from this.
Where AI shows up
AI shows up in different roles in different parts of running a campaign. Grimoire is designed around all three.
At the live table
You roll dice, narrate, react, adjudicate. If the players bring a question that needs Grimoire canon, you check Grimoire (with or without AI between you and the data). Whatever happens at the table is whatever you say happens. Grimoire only updates when you tell it to.
This is the layer most AI-D&D products quietly assume away. We don't.
Between sessions
You sit with your prep doc; your AI reads Grimoire MCP; together you outline the next session beats, draft three rumors that fit your current city, project what House Vale does next given their motivations, and surface the four open threads that touch the players' destination.
This is where Grimoire spends most of its useful time. Canon enforcement keeps the AI's suggestions grounded; narrative state tracking keeps its recaps honest; human-in-the-loop means you cherry-pick what gets committed.
The pre-built campaign
A published adventure, a setting bible, a community-shared world, all shipped as a Grimoire database with structured entities and canon already modeled. Your AI knows the world from the moment you import it.
This is the platform direction. A publisher ships their campaign as a Grimoire database; you buy and run it. You still run the table. The AI just helps you stay in canon for a world you didn't write.
The honest comparison
AI is good at
AI is NOT good at
The first list is what we built Grimoire for. The second list is why the AI is the assistant, not the DM.
What's actually different
Some products in this space (AIDungeonMaster.ai, Friends & Fables, AI Realm, AI Dungeon) try to replace the DM. They run the game; you're a player. That's a real product; some people enjoy it. It's just not what we are.
Other products (LoreKeeper.ai, Tabletop Arc, Quest Portal, Archivist AI, GM Assistant) sit somewhere in the middle. They bundle their own AI, they generate content for you, they record sessions, and they assume the human DM will be present somewhere in the workflow but blur where exactly.
Grimoire is the only TTRPG campaign manager with MCP as the integration model, BYO-client as the structural choice, and canon enforcement as the central design constraint. The AI is whichever one you pick. The canon is yours. The DM is you. The platform-direction toward publisher content respects all of the above.
If the test for "AI for DMs" is whether the human DM is structurally necessary to the product, Grimoire passes. Most products in this space fail this test by accident.
What it looks like in practice
A canon question
Who's the god of war in my setting?
Generic AI
"In the Forgotten Realms, Tempus is the god of war..."
AI-as-DM tool
Improvises a god of war on the spot, with no relation to your actual pantheon. This answer becomes canon for that tool's next session, because it has no source of truth.
Grimoire (AI for DMs)
In your setting, Tempus was deposed during the Sundering; Helm holds the war domain now. (Source: Constitution, World Rules, established session 1.)
A character prediction
How would Queen Mira react to her brother's betrayal?
Generic AI
"A queen betrayed by her brother would likely feel..."
AI-as-DM tool
Tries to roleplay Mira; reads her as a generic queen trope; misses that she already suspects Cyrus is the cult's silent backer.
Grimoire (AI for DMs)
Mira already suspects Cyrus is the cult's backer (GM-secret). She wouldn't be surprised by his betrayal, she'd be confirmed. She'd move on the cult immediately using the Crown's evidence-laundering channel through House Vale. (Source: NPC Mira motivations plus active arc "Vale succession".)
A homebrew mechanic
Player rolled a nat 20 on the crit. Damage?
Generic AI
"Roll all damage dice twice and add modifiers once..."
AI-as-DM tool
Applies generic crit rules; doesn't know your homebrew.
Grimoire (AI for DMs)
In your setting, crits restore HP equal to the rolled damage instead of dealing it, your custom mechanic from session 0. Roll 1d8 normally and the target heals that much. (Source: Custom Mechanics, "Crit-as-Heal".)
The pattern: Grimoire's answers aren't smarter than generic AI. They're correctly grounded in your canon. That's the whole product.
What's coming
The current product is everything above: a campaign manager where you build your world, and an MCP integration that lets your AI read it.
The platform direction extends this. Imagine a publisher ships their campaign (a homebrew megadungeon, a community-shared setting) as a Grimoire database. You buy or download it. The world's lore, NPCs, factions, locations, custom mechanics, pantheon, and plot threads are all there as typed entities, already modeled. Your AI knows the campaign from the moment you import it.
You still run the table. The AI helps you stay in canon for a world you didn't write. The publisher reaches an audience they couldn't reach before: DMs who want pre-built campaigns that work with their AI workflow on day one, not PDFs that need re-paraphrasing into a chat every session.
We're early on this. If you're a publisher and this is interesting, the contact form reaches the person who'd work on it with you.
Free to try, BYO AI
Grimoire's free tier covers Grimoire MCP: unlimited entities and AI queries on one campaign, forever. No 14-day trial, no credit card, no time limit.
Your AI client's free tier covers the other end. Claude.ai and ChatGPT both support one custom MCP connector on their free tier. That connector can be Grimoire. End-to-end free to try.
We never charge for AI tokens. You pay your AI client directly. When a better model ships, you're on it the same day; we don't have to scramble to integrate. And if you ever want to run the campaign manager with no AI at all, that works too: the entities, knowledge graphs, wiki, and player portal are a complete product on their own. The AI is the layer, not the floor.
Questions, answered
No. Grimoire is built around the human DM. The AI helps you prep, recall canon, draft recaps, and project plausible NPC moves between sessions. At the table, you run the game. This is a structural design choice, not a temporary limitation: the products that run sessions for you are a different category (AI Dungeon, AIDungeonMaster.ai, Friends & Fables). Both categories are real; we're solidly in this one.
AI as DM: the AI roleplays the world, runs encounters, adjudicates rules. You play. AI for DM: the AI helps you prepare and remember; you do all the live work. The first category is constrained by what AI is structurally bad at (mechanics, memory across long contexts, edge-case rules calls). The second category benefits from what AI is structurally good at (synthesis, drafting, traversing structured knowledge). Grimoire is firmly in the second.
Because the right AI is whichever one ships next. A product that bundles a specific model gets stale every six months as the model market updates. MCP lets you pick the client; when a better model arrives, you're on it the same day. We also don't charge for AI tokens: you pay your client directly, no markup, no quota.
Less than you'd think, structurally. Grimoire's Constitution, World Rules, and Custom Mechanics entities load before any AI query. When the AI is asked "who's the god of war," it reads your pantheon first; it can't override "Tempus is dead" with "Tempus is the god of war." The AI will still make small drafting choices (NPC dialogue style, rumor framing) that aren't strictly in the source; that's generation, not hallucination. The boundary the canon system enforces is "established facts you've written down."
No. Grimoire's visibility tiers are enforced server-side. When a player connects their own AI to Grimoire through MCP, the connection is scoped to their permitted view of the campaign. Anything tagged GM-secret never reaches the player or their AI, even mid-conversation, even if the player asks the right question. The server filters before the data leaves.
Eventually, by design. Right now, you'd need to re-model the published campaign as a Grimoire campaign yourself, which most homebrew DMs do anyway because they want to adjust it. Long-term, we want publishers to ship campaigns as Grimoire databases directly; that's the platform direction.
Claude.ai (web and desktop), ChatGPT (Plus/Pro tiers with custom connectors), Cursor, Claude Code, Codex CLI, and any client that supports the official MCP protocol. The list is growing fast. Grimoire is in the official MCP Registry as bot.ttrpg/grimoire, so any client that pulls from the registry sees us automatically.
Yes. Grimoire's free tier covers MCP integration, the worldbuilding (entity creation, knowledge graphs, wiki), and all the canon enforcement. The free tier of Claude.ai or ChatGPT covers one custom MCP connector on their side. There is no upsell required to use AI with Grimoire.
Already a DM with a homebrew campaign? Bring it. The schema fills in faster than you'd guess.