SignMaster in Claude
SignMaster works inside Claude as a custom connector. Once it's added, you can ask Claude where a contract stands, start a draft from one of your templates or nudge a slow signer, in plain language, from Claude on the web, on the desktop or on your phone.
Updated November 5, 2026 · 2 min read
On this page
Add SignMaster to Claude
- 1
Copy the address
In SignMaster, open Settings › Connect an AI. The Claude card shows the connector address to copy.
- 2
Add a custom connector
In Claude, go to Customize › Connectors, choose + Add, then Add custom connector. Name it SignMaster, paste the address and choose Continue.
- 3
Keep the sign-in settings
Claude detects that SignMaster uses OAuth sign-in. Keep its recommended option, Use Claude's published identity, and choose Add.
- 4
Connect and allow
Choose Connect. A SignMaster page opens: sign in, check which workspace Claude will use, untick anything you don't want it to do, and press Allow access.
On Claude's Team and Enterprise plans, an owner adds the connector for the organization first, under Organization settings › Connectors, and each member then connects their own SignMaster account. Claude's Free plan allows one custom connector. Using Claude Code instead? Run claude mcp add --transport http signmaster followed by the address, then sign in when it asks.
What to ask
- What's waiting on me in SignMaster?
- Where's the Henderson roofing contract, and who hasn't signed?
- Start a draft from my Service agreement template for Dana Ruiz, dana@example.com, at 450 Elm Street.
- Remind everyone who hasn't signed the Oak Street lease.
- Write a simple pet addendum and save it in SignMaster as a template.
- How many envelopes have we sent this month?
- Get me a link to the signed copy of the Baker contract.
Claude asks, you approve
Lookups and drafts happen straight away. Anything that would email someone, like sending, reminding or voiding, is held in SignMaster as a request, and Claude tells you it's waiting. Open Settings › Connect an AI, check exactly who would get what, and choose Approve or Deny. A request nobody answers expires. After you approve, ask Claude to carry on and it reports the result.
What Claude can see
Claude works as you, with your role's access, cut down further by the permissions you left ticked when you connected: seeing envelopes, preparing and sending them, seeing templates, searching contacts and downloading signed copies. If your role is viewer, the connection can only read. SignMaster checks those limits again on every request, not just when you connect.
Templates Claude writes for you are drafts of legal wording by an AI. Read them before you send them to a customer, the same as you would a template from anywhere else.
Disconnect any time
Every connected app is listed in Settings › Connect an AI. Choose Disconnect next to Claude and it loses access at once. Remove the connector in Claude too, so it stops offering SignMaster in your chats.
Questions? Answers.
Does it cost extra?
No. Connect an AI is on every SignMaster plan. An envelope Claude drafts and you send counts like any other, so the Free plan's 3 envelopes a month still apply.
Can Claude send a contract without asking me?
No. Sends, reminders and voids wait for your approval in SignMaster, every time.
Does it work in the Claude mobile app?
Yes. Once the connector is added to your account, it's available in Claude on the web, the desktop app and the phone app.