Help Center / api

Connect OSIR to Claude

Add OSIR to Claude as a custom connector and Claude can search and register domains, manage DNS, order servers, host email and deploy sites for you. There are two ways to connect and both take under two minutes. You do not need an install, a config file or an API key.

No sign-in: paste one URL. You log in inside the chat only when a task needs your account.
OAuth: paste a URL and a client ID, and sign in once when you add the connector.

We recommend No sign-in for most people, because your chat never holds access to your account when you are not using it.

Which option should you choose?

	No sign-in (recommended)	OAuth
Server URL	`https://be.osir.com/mcp/http`	`https://be.osir.com/mcp/oauth`
Authentication setting	No sign-in	Sign in now
OAuth client setting	Not shown	Use your own OAuth client, Client ID `mcp-client`
When you log in	In the chat, the first time a task needs your account	Once, when you add the connector
How long access lasts	One conversation: ends after 30 minutes idle, 8 hours at most, or when you say "log me out"	Until you disconnect the connector or the sign-in expires
Works without an OSIR account	Yes: searches, prices and the catalog	No: you sign in before any tool works
Best for	Occasional use, shared computers, least standing access	Daily use, no login step in each chat

Option A: No sign-in

You paste one URL and log in inside the chat when you need to.

In Claude, open Settings then Connectors and click Add custom connector.
For Name, enter OSIR.
For Remote MCP server URL, enter https://be.osir.com/mcp/http.
Under Authentication, choose No sign-in. Claude usually shows it as "Detected" already.
Leave Request headers empty. OSIR does not use API keys.
Click Add.

Claude warns that anyone with the URL can use the connector. That is expected. Without a login the URL only gives public information such as availability and prices. Anything that touches your account needs you to log in.

Logging in during a chat

Ask for something that needs your account, such as "What is my OSIR balance?"
Claude replies with a link to auth.osir.com and a short code.
Open the link, check that the code matches, and approve.
Tell Claude you are done. It finishes the login and carries on with your request.

The login applies to that conversation only. A new chat asks you to log in again.

Option B: OAuth

You sign in once in your browser and the connector stays signed in. The URL is different from Option A: it ends in /mcp/oauth.

In Claude, open Settings then Connectors and click Add custom connector.
For Name, enter OSIR.
For Remote MCP server URL, enter https://be.osir.com/mcp/oauth.
Under Authentication, choose Sign in now.
Under OAuth client, choose Use your own OAuth client.
For Client ID, enter mcp-client. Leave Client secret blank.
Leave Request headers empty.
Click Add. A browser window opens on auth.osir.com.
Sign in with your OSIR account and approve. The connector now shows as connected.

Do not choose the other OAuth client options. "Use Claude's published identity" and "Register automatically" do not work with OSIR yet, and Claude may pre-select the first one, so change it to Use your own OAuth client.

mcp-client is a public identifier, not a password, so it is safe to share.

What can you ask once it is connected?

Start a new chat, make sure the OSIR connector is on, then try these.

Ask Claude	Needs login
"Is coolstartup.io available, and what does it cost?"	No
"Suggest five short .com names for a coffee brand."	No
"What is my OSIR account balance?"	Yes
"Register coolstartup.io for two years."	Yes
"Point coolstartup.io at 192.0.2.10."	Yes
"Spin up a 2 vCPU server in Frankfurt running Ubuntu."	Yes

The connector exposes 105 tools and 11 prompts covering domains, DNS, email, VPS, apps and billing. Anything that costs money or deletes something happens in two steps: Claude first shows you an itemized summary and only goes ahead after you say yes.

Signing out and security

No sign-in: say "log me out" in the chat and access ends at once. It also ends by itself after 30 minutes idle, or 8 hours at most.
OAuth: go to Settings then Connectors, open OSIR and click Disconnect. Do this on any computer other people can use. Until you disconnect, anyone with your Claude account can reach your OSIR account.
Your OSIR password always goes to auth.osir.com, never to Claude. Before you approve a login, check that the address bar shows auth.osir.com.
OSIR never asks you for an API key, password or card number in the chat.

Troubleshooting

What you see	Fix
OAuth sign-in fails with an error about the client or registration	Edit the connector: under OAuth client, choose Use your own OAuth client and enter `mcp-client`.
"Authentication required" with the No sign-in option	That is normal. Let Claude start the login, approve the code at `auth.osir.com`, then continue.
"The provided sessionKey is expired"	The chat's login ran out. Ask Claude to log you in again.
Every tool returns 401 on the No sign-in option	The URL is wrong. Option A uses `/mcp/http`, not `/mcp/oauth`.
Tools return "Forbidden" (403) after an OAuth sign-in	The connector may be using an old registration. Remove it, add it again with `mcp-client`, and sign in again.
Claude does not use OSIR at all	In the chat, check that the OSIR connector is turned on in the tools menu.
"OSIR is set up as not requiring sign-in, but the server asked for sign-in when checked (status 401)"	Remove the connector and add it again. See the first question below.

Still stuck? Contact OSIR support with the time of the error and the option you chose.

Connector questions

Claude says "OSIR is set up as not requiring sign-in, but the server asked for sign-in when checked (status 401)". What do I do?

Remove the OSIR connector completely, then add it again. Editing the existing one is not enough, because Claude keeps the result of its first check. Go to Settings then Connectors, open OSIR, click Remove, then follow Option A again with https://be.osir.com/mcp/http and No sign-in. Also check that the URL ends in /mcp/http, because /mcp/oauth always asks for sign-in.

Can I switch from one option to the other?

Yes. Remove the connector, then add it again with the other URL and settings. The two options use different URLs, so changing only the Authentication setting does not work.

Something that used to work stopped working. Why?

Claude remembers a connector's settings from when you added it, including the result of its first check against the server. Removing the connector and adding it again makes Claude check afresh, and that fixes most connection errors.

Other clients

The same remote server URL works in any MCP client that supports a remote streamable HTTP server, including ChatGPT, Cursor, Windsurf, Claude Code and open-source agents. See the MCP server page for the full tool catalog, the AI integration guide for MCP, A2A and REST together, and the MCP protocol guide for how the protocol works.