Context Layer

One memory for every AI agent.

A self-hostable, remote MCP server that gives every agent you use (Claude, Claude Code, Cursor, ChatGPT, …) the same durable memory about you. Vendor-independent. Your data, on your own Cloudflare account.

Hosted beta · Self-host · MCP tools · Contributing

Why

Every agent you use keeps its own notes about you, and none of them talk to each other. Switch from Claude to Cursor to ChatGPT and you start from zero each time. Context Layer is a single MCP endpoint that all of them connect to, so a lesson learned in one tool applies in every other.

• Vendor-independent. Works with any MCP client via OAuth 2.1 or a personal token.

• User-owned. Runs on your Cloudflare account. Export or delete everything at any time.

• Agent-driven setup. Paste one line into any agent and it configures itself, modeled on Notion's agent setup prompt.

• Durable, not just a scratchpad. Memories with supersede history, versioned Markdown documents, reusable skills, and "lessons" (mistakes an agent made with you and what to do instead).

• Multi-user and isolated. Invite-only accounts, per-user vector namespaces, every query scoped by user_id.

Related MCP server: clude-mcp

Quick start

Use the hosted version

The hosted instance is an invite-only beta. Join the waitlist at https://context-layer.winter-limit-1658.workers.dev. Once you have an account, paste this into any agent:

Set up my Personal Context Layer by following https://context-layer.winter-limit-1658.workers.dev/setup

The agent connects over MCP, installs custom instructions for when to read and write, creates an Agent Operating Guide, and optionally imports existing context.

Connect a client manually

Self-hosting

You need a Cloudflare account with Workers, D1, KV, Vectorize and Workers AI enabled (all available on the free tier).

git clone https://github.com/kuehlpaul/personal-context-layer.git
cd personal-context-layer
npm install

# 1. Create the resources and put their IDs into wrangler.jsonc
npx wrangler d1 create context-layer
npx wrangler kv namespace create OAUTH_KV
npx wrangler vectorize create context-layer --dimensions=1024 --metric=cosine

# 2. Set secrets
npx wrangler secret put SESSION_SECRET      # openssl rand -hex 32
npx wrangler secret put CONSENT_SECRET      # openssl rand -hex 32
npx wrangler secret put RESEND_API_KEY      # optional, enables email sending

# 3. Migrate and deploy
npm run db:migrate:remote
npx wrangler deploy

Then set PUBLIC_URL and ADMIN_EMAIL in wrangler.jsonc, open https://<your-worker>/join and sign up with the admin email. The first signup with that address needs no invite code and becomes the admin account.

Configuration

Upgrading an existing deployment

git pull
npm install
npm run db:migrate:remote
npx wrangler deploy

Migrations are additive. 0003 introduces accounts and tags pre-existing single-owner data as owner; the ADMIN_EMAIL account inherits it on first signup, re-embeds it into its own namespace, and existing OAuth grants keep working. The old OWNER_PASSWORD secret is no longer used and can be deleted.

How it works

┌───────────┐  ┌────────────┐  ┌────────┐  ┌─────────┐
│  Claude   │  │ Claude Code│  │ Cursor │  │ ChatGPT │   … any MCP client
└─────┬─────┘  └──────┬─────┘  └───┬────┘  └────┬────┘
      └───────────────┴────────────┴─────────────┘
                             │  OAuth 2.1 or pcl_… token
                             ▼
                  ┌───────────────────────┐
                  │   Cloudflare Worker   │  /mcp  · /setup · /ui · /admin
                  └──┬──────┬──────┬──────┘
                     │      │      │
                  ┌──▼─┐ ┌──▼──┐ ┌─▼────────┐
                  │ D1 │ │ KV  │ │Vectorize │ + Workers AI embeddings
                  └────┘ └─────┘ └──────────┘

Routes

MCP tools

Read

Write (requires scope mcp:write)

Security and access control

• Waitlist entries grant nothing. An admin turns one into a single-use invite bound to that email (14 days). Free-form invites with N uses and an optional expiry exist too.

• Accounts are isolated. Every table carries user_id, every query in src/store.ts filters on it, and vectors live in a per-user Vectorize namespace.

• Disabling an account kills its sessions, tokens and OAuth grants immediately and is checked on every MCP request. Deleting removes all rows, vectors and grants. Changing a password signs out every other session.

• Legacy grants from before accounts existed are bound once, at claim time, to the account that adopted the single-owner data, and never re-resolved from roles.

• Independently audited for cross-account access on 2026-11-07. Findings were fixed in migration 0004 and the matching code.

Found a vulnerability? Please open a private security advisory on GitHub instead of a public issue.

Development

npm install
cp .dev.vars.example .dev.vars   # fill in the secrets
npm run db:migrate:local
npm run dev                      # http://localhost:8787

Workers AI and Vectorize have no local emulation and need a remote connection (account_id in wrangler.jsonc). Without them, search falls back to keyword matching.

Project layout

src/
  index.ts        Router, OAuth provider wiring, cron entry
  mcp.ts          MCP server and tool definitions
  store.ts        All D1 + Vectorize access, bound to one user
  accounts.ts     Users, passwords, sessions, waitlist, invites, personal tokens
  auth.ts         OAuth 2.1 server, token auth, login / join / reset pages
  admin.ts        Admin panel
  ui.ts           User-facing web app
  setup.ts        /setup guide content served to agents
  setup-page.ts   Docs-style HTML shell for /setup
  landing.ts      Public landing page and waitlist
  daily.ts        Daily maintenance report (cron)
  html.ts         Shared HTML helpers and layout
migrations/       D1 schema, applied in order

Contributing

Issues and pull requests are welcome.

1. Fork the repo and create a branch from main.

2. Run npm run typecheck before opening a PR.

3. Schema changes go into a new numbered file in migrations/. Never edit an applied migration.

4. Anything that touches src/store.ts must keep filtering on user_id.

For larger changes, open an issue first so we can discuss the approach.

License

MIT © 2026 Paul Kühl