Short answer: start with servers that need no sign-in and only read, add OAuth servers whose scopes are read-only next, and leave anything that writes to a shared account — or that uses a token you’d hate to see misused — for last, behind an approval step. The order matters less for what you get out of each tool and more for how much damage a bad first guess can do while you’re still learning what MCP actually hands over.

Most “getting started with MCP” guides list servers by category — dev tools, productivity, finance — and leave the order up to you. That’s fine once you know what you’re doing. If you’re the first person on your team connecting anything, the order you pick is itself a risk decision, whether you treat it as one or not.

Tier 1: no sign-in, read-only

The lowest-stakes place to start is a server that needs no account at all — nothing to revoke, nothing tied to your identity, nothing that can act on your behalf because it was never handed any authority in the first place. Docs and reference servers (library documentation, a public GitHub repo reader, a web-scraping tool) are the most common examples. The worst case if the tool misbehaves is a bad answer, not a leaked credential or an action taken in your name.

This tier is also the right place to get a feel for how your AI client actually surfaces a tool call — what it shows you before running one, what the result looks like, how a server shows up in your connection list — before anything you connect can touch data you’d care about losing.

Tier 2: OAuth, read-only scopes, from a vendor you already trust

Next come servers that need a real sign-in but only ask to read: your calendar, your analytics, your issue tracker. You’re now trusting a vendor’s OAuth screen to accurately describe what it’s requesting, so stick to vendors whose product you already use and whose data exposure you understand. Read the consent screen instead of clicking through it — our piece on what MCP OAuth scopes actually grant is worth five minutes before you approve anything here.

Worth knowing going in: a meaningful share of MCP servers in the wild only admit clients the vendor has pre-approved, so a new AI client can hit an “unauthorized client” error on a server that otherwise works fine for everyone else. That is a vendor policy, not a sign your setup is broken — see why that error shows up if you hit it.

Tier 3: write-capable, or a shared account

Save for last anything that can send a message, create a record, delete something, or touch an account other people also use — Slack, a shared Notion workspace, a ticket tracker, a payments tool. These are exactly the tools where a model acting on injected or misread instructions does something you can’t quietly undo. By the time you connect one of these, you should already have an opinion on which specific actions need a human to confirm before they run, not just whether the server as a whole feels trustworthy. Our post on keeping a human in the loop for sensitive actions covers how to draw that line tool by tool rather than server by server.

This tier is also where excessive agency shows up most: a tool that claims to “update a record” may carry a generic action field capable of far more than the one update you intended to allow. Read the tool list, not just the server’s marketing description, before you decide this one is fine.

Scan every server regardless of tier

The tiering above is about blast radius if a tool is used exactly as advertised. It says nothing about whether a tool’s description is hiding an instruction aimed at the model instead of a human reader — a no-sign-in documentation server can carry a poisoned description just as easily as a payments tool can. Run every server through a security scan before connecting it, no matter which tier it lands in, and re-scan after updates: a server that passed clean once can still change later. That drift risk, and what a scan can and can’t catch, is covered in our breakdown of what an MCP scanner actually checks.

A simple rollout order

  1. Connect one or two no-sign-in, read-only servers. Learn how your client shows tool calls and results.
  2. Scan each server before connecting it, regardless of tier.
  3. Add OAuth servers with read-only scopes, from vendors whose product you already use.
  4. Read the consent screen on every OAuth grant — don’t assume the scopes match the server’s name.
  5. Add write-capable or shared-account servers last, and decide per tool which actions need approval before they run.
  6. Re-scan after any server update, and re-review scopes if a new version asks for more than it used to.
How gate helps: every server you add through gate — any tier — is scanned for prompt injection and hidden instructions before it goes live, and re-checked when its tools change. You set an allow, ask, or block rule per tool rather than per server, so a Tier 3 server can still have its reads open and its writes behind approval. Connect once through one gateway URL and every client you use — Claude, Cursor, ChatGPT — sees the same rules, instead of you repeating this tiering exercise separately in each one.

The bottom line

There’s no MCP-specific reason a documentation lookup and a payments tool should be connected with the same level of caution, and treating them identically is how a reasonable-looking first setup ends up with more reach than anyone actually decided to grant. Start with what can’t act on your behalf, add what can only read, and make the write-capable tools earn their place one tool at a time.