MCP server · Claude · Cursor · Copilot

Give your AI permanent memory.

SubVault is an MCP server that gives Claude, Cursor, and Copilot shared memory. Say vault to save a session. Say remember to load it back later, in the same tool or a different one.

$ curl subvault.ai/install.sh | bash -s YOUR_KEY
How it works

What gets saved.

When you say vault, your AI sends the session's facts, decisions, and action items to SubVault. When you say remember, SubVault sends back the ones that match, in about 2,000 tokens. It works in every MCP client, so what you save in Claude is available in Cursor.

decision

Decisions + reasoning

Chose PostgreSQL over MongoDB. Billing needs relational integrity
person

People + relationships

Sarah owns frontend, Mike handles DevOps, report to Lisa
action

Action items + status

Update billing webhook before Friday. Blocked on Stripe keys
fact

Project context

API at v2, migration from v1 in progress, 3 endpoints left
Transcripts & built-in memory
×Dumps entire transcripts
×No relevance ranking
×Fills the context window
×Same info every time
×Locked to one AI tool
SubVault
Keeps decisions, people, open threads
Ranks by who said it, how fresh, how relevant
The current truth in ~2,000 tokens
Shapes context to the question
One memory, under every MCP client
Your data

Where your data lives.

When you say vault, your AI extracts the facts, decisions, and action items from the session and sends those, not the transcript. A 1,000-word conversation arrives as a dozen short entries. Everything is stored in a single SQLite database that you can delete at any time.

Only saved items are sent

When you vault, your AI sends the items being saved and nothing else. SubVault has no access to the rest of the conversation.

One vault, one file

Each vault is its own SQLite database. There are no shared tables between users.

Deletion

Deleting your vault deletes the database. Backups are removed on the retention cycle.

Standard format

Your vault is one standard SQLite database, not a proprietary store. Export arrives later in early access.

See it work

Recorded sessions.

Vault a research session

Say "vault this." The decisions, facts, and action items are saved.

Remember across sessions

Say "remember what I decided about pricing." The matching items come back as context.

Vault a project session

Architecture decisions are saved with their reasoning and available from any MCP client.

Remember project context

A new session starts with the project's prior decisions already loaded.

Under the hood

What happens when you say vault.

distill

Structured extraction

A session is saved as separate facts, decisions, people, and action items. Each entry makes sense without the original conversation.

score

Ranking

Results are ranked by source, recency, and relevance. Things you stated outrank things the model inferred.

route

Query classification

"Who is Sarah?" returns people. "What's the status?" returns action items.

assemble

Token budget

Every response fits a fixed budget of about 2,000 tokens.

dedup

Deduplication

Items are hashed on save. Vaulting the same thing twice stores it once.

sanitize

Injection protection

Every item is checked for prompt-injection patterns before it enters your AI's context.

Performance

Current production numbers.

Measured on the production server.

~300msmedian context assembly time
~2,000tokens per assembled context
1SQLite database per vault
Install

Set up in 30 seconds.

01

Create an account

Sign up at subvault.ai and copy your API key from the dashboard.

02

Run the installer

One command configures Claude Desktop, Cursor, and VS Code.

03

Say vault or remember

Vault saves the session. Remember loads it back in any connected tool.

$curl -fsSL https://subvault.ai/install.sh | bash -s YOUR_API_KEY
→ found Claude Desktop, Cursor, VS Code
subvault connected
configures every MCP client on your machine

Prefer a file? Download subvault.mcpb and double-click it. Claude will ask to enable the extension.

Pricing

Early access is free.

Stop re-explaining yourself

Set it up before your next session.

Install, then say vault at the end of your next session.