A coding agent is only as useful as the tools it can reach. Most of your project’s real context lives outside the editor: open issues, error reports, CI status. Pulling that data into a chat used to mean handing out API keys and managing tokens by hand. Tarsk now supports OAuth for remote MCP servers, so your agent can sign in to a service the same way you do.
This post explains the new OAuth support and walks through adding Sentry, one of the servers already in the Tarsk marketplace.
What OAuth for MCP servers does
Remote MCP servers (also called HTTP or Streamable HTTP servers) run as a web service rather than a local process on your machine. Some of them, like Sentry’s hosted server, expect you to log in with your own account instead of pasting a token.
OAuth handles that login for you:
- You add the server by URL. Tarsk opens your browser to the service’s sign-in screen.
- You approve the access the server asks for, scoped to your account and organizations.
- Tarsk stores the resulting credentials encrypted and reuses them on later sessions.
- When you no longer want the connection, a single “Sign out” removes it.
For services that support dynamic client registration, this needs no setup on your side. You do not create an app, copy a client ID, or store a secret. The browser login is the whole process.
For servers that do not support dynamic client registration, Tarsk still supports OAuth, but you supply a client ID and secret that you create once in that service’s developer settings. More on that below.
Where to add a server
Open Settings → MCP Servers.
You have two paths:
- Marketplace: a list of popular servers, including Sentry, GitHub, Supabase, Cloudflare, and others. Click one to install it into your project.
- Add Server: configure a server yourself, either a local (stdio) server or a remote HTTP/SSE server by URL.
Tarsk stores server configs in .agents/mcp.json at your project root, falling back to mcp.json. Installed servers connect when a thread starts, and you can scope them to a single project or apply them globally.
For servers that use OAuth, the row in the Installed list shows a Sign in button after install. Local token-based servers instead ask for environment variables.
Adding Sentry, step by step
Sentry’s hosted MCP server lets your agent read issues, projects, and error context from your Sentry account. It is one of the marketplace entries, so adding it is a few clicks.
- Open Settings → MCP Servers.
- Find Sentry in the marketplace and click Install.
- In the Installed list, the Sentry row now shows Sign in. Click it.
- Your browser opens to Sentry. Sign in to the account that holds your organization and projects.
- Approve the access Sentry requests. The server asks for read access to your organizations and projects and read or write access to issues.
- The browser returns to Tarsk and the row now reads Sign out and Authorized. You can click Test Connection to confirm the server is reachable and its tools are discoverable.
That is the entire setup. No API key, no token to copy, no environment variable to fill in.
If you want to limit what the agent can see, Sentry supports scoped URLs that point at a single organization or project:
https://mcp.sentry.dev/mcp: every organization and project you can accesshttps://mcp.sentry.dev/mcp/{organizationSlug}: one organizationhttps://mcp.sentry.dev/mcp/{organizationSlug}/{projectSlug}: one project
Scoping to a project is the safest default. The agent only sees what you pointed it at.
EU and self-hosted accounts
Sentry Cloud accounts in the EU (de.sentry.io) authenticate through the same OAuth flow as US accounts. If you run Sentry on your own infrastructure, the marketplace entry will not work; use the local server variant and supply a Sentry user auth token instead, following Sentry’s own documentation.
What you can do once connected
After sign-in, your agent gains Sentry’s tools. A few that change daily debugging:
- Inspect issues: open an issue with its stack trace, file locations, and context, without leaving the chat.
- List and search issues: filter open issues by project, status, or free text.
- Read projects and teams: list the projects in an organization and their configuration.
- Trace details: pull a distributed trace to see where a request broke down.
- Sentry docs: ask the agent to fetch a Sentry documentation page.
A practical example: paste a stack trace into the chat and ask the agent to find the matching Sentry issue, summarize the recent events, and suggest a likely cause. The agent reads the issue directly instead of you copying fields back and forth.
Some Sentry tools, including the AI-assisted root-cause analysis, depend on features you enable in your Sentry organization. Check Sentry’s documentation for what your plan supports.
Servers that need a client ID and secret
Not every remote server supports dynamic client registration. GitHub Copilot’s MCP server is one example. For these, Tarsk exposes an OAuth client section in the server editor where you enter a client ID and secret.
The flow:
- In the service’s developer settings, create an OAuth app.
- Set the callback URL to
http://localhost:PORT/callback, where the port matches the one Tarsk shows in the server editor. - Copy the client ID and secret into Tarsk.
- Click Sign in. Tarsk opens the browser, you approve access, and the callback completes the login.
This path exists for servers that cannot register themselves. If a server does support dynamic client registration, the simpler marketplace flow above is all you need.
Connection and cleanup
Remote OAuth servers keep their credentials encrypted and tied to your project. You can confirm a server works with Test Connection, which checks that it starts, authenticates, and exposes tools.
To remove a server, open its editor and delete it; to end the OAuth session without removing the server, click Sign out on the row. Either way, the stored credentials stop being used.
Summary
- Tarsk now supports OAuth for remote MCP servers, so your agent can sign in to services with your own account instead of static tokens.
- Sentry is available in the MCP marketplace and connects through a browser sign-in with no API key.
- Scope the connection to a single project for the tightest access.
- Servers without dynamic client registration still work: create an OAuth app, set the callback, and supply a client ID and secret.
Open Settings → MCP Servers and try the Sentry entry, or add your own remote server by URL. Your agent gets the context it was missing.