Take your Message Library into Claude
Your brand strategy lives in OnMessage. Your team writes in a dozen other places. The OnMessage connector closes that gap: connect once, and Claude works from your approved audiences, offerings, voice, and writing guidelines instead of guessing.
Reads never consume credits. Your Message Library stays the single source of truth, wherever the work happens.
One library, every AI tool
Without it, every session starts from zero. Someone pastes in the positioning, half-remembers the audience, and the output drifts. With it, Claude reads the same approved strategy your team writes from in the app, and writes back to it for anyone whose role allows that.
Access mirrors your OnMessage permissions exactly. The connector cannot see or change anything the same person could not see or change while signed in to the app.
You need: a paid OnMessage plan or an active trial, your normal OnMessage login, and an AI app that supports MCP: Claude on web, desktop, and mobile, Claude Code, or another client like Cursor, Windsurf, or VS Code.
Connect in four steps
Copy the connector URL
This is the only value you need. It is the same for every OnMessage customer. Your account, not the URL, determines what you can reach.
Add it in your AI app
In Claude, open Settings → Connectors → Add custom connector, then paste the URL. In Claude Code, run the command below instead.
Sign in and approve access
Your browser opens an OnMessage sign-in page. Sign in as you normally would, review what the app is asking for, and approve. OnMessage never sees the AI app’s account, and the AI app never sees your OnMessage password.
Ask for something from your library
Try “What does our Message Library say about our primary audience?” Claude reads the relevant files and answers from your strategy. You are connected.
Step-by-step instructions for each supported app are in the OnMessage app under Settings → Integrations, alongside a list of the apps currently connected to your account.
What the connector can do
The connector never widens access. Someone whose role cannot open the Message Library in OnMessage cannot connect at all, and anyone who does connect sees only the files their role already lets them read.
Everyone can browse the library, read any file they have access to, and search across everything, including inside large uploaded documents.
Roles with edit access can also create and edit files, save documents like transcripts and research reports into the library, and update brand strategy such as offerings, audiences, and glossary terms. Every change is versioned and reversible in the app.
Agencies can switch which client brand the connector is reading, with the active brand named on every connection.
A full list of what each AI app can do is in the OnMessage app under Settings → Integrations.
Your permissions travel with you
Connections use OAuth 2.1 with PKCE. You authorize the app in your browser, so no password, token, or key is ever pasted into the AI app.
Permissions are enforced on the server on every request: a role without Message Library access is refused at the connection, and each file is then checked against the same read and write roles the app uses. Revoke someone’s access in OnMessage and their connected AI apps lose it on their next request. You can see and disconnect every connected app under Settings → Integrations.
How OnMessage handles your data is covered in full in the privacy policy.
Frequently Asked Questions
Learn more about how OnMessage works.
No. Reading your Message Library through the connector does not consume OnMessage credits. Credits apply to content generation inside OnMessage.
Yes. Anyone in your organization on a paid plan connects with their own account, and each person's access matches their own role. There is no shared connector credential to distribute or rotate.
Only what you can see in OnMessage, and only when it calls a connector tool. The connector reads your Message Library. It does not read your OnMessage chats, your billing details, or anything belonging to another organization.
Only if your role already allows it, and some files are read-only by design. Anything projected from your structured Message Library (brand foundation, offerings, audiences) is edited through the strategy tools or in the app, never overwritten as a file. Everything the connector does write is versioned and reversible.
Your account sees every client organization you already have access to. The connector reads one at a time, names the active one on every connection, and switches when you ask it to. The agency's own organization needs an active workspace before members can connect.
Any app that supports remote MCP servers can connect using the same URL, including Cursor, Windsurf, and VS Code. Support varies by app and by plan, and some tiers allow read-only connectors only. Setup notes for each app are in Settings → Integrations.
If the connection is refused, check that your plan is active and that you are connecting with the account that has access to the organization you expect. If a tool you expected is missing, it is almost always a role that lacks edit access to that page. Email contact@onmessage.app and we will take a look.
Every tool your team writes in, on message
Connect once. Work from approved strategy everywhere.