Hundreds of MCP Servers and Claude Skills, and Barely Any Are Truly Free and Open Source. I Checked Them One by One and Turned It Into a Directory

Last week I wanted to add a few MCP servers to Claude. I searched around, and the more I searched the more annoyed I got.

It’s not that there was nothing to choose from — it’s that there was too much, and you can’t tell the real from the fake. There are already hundreds of MCP servers alone, and Claude’s skills frameworks keep showing up in waves. But the moment you try to pick the ones that are actually free and install-and-go, you hit one trap after another.

In MCP land, the word “free” comes in at least three fake versions

Fake version one: it’s only “free” if you hand over an API key. Exa, Tavily, Brave Search, Firecrawl, Notion, Supabase… the clients really are open source and really cost nothing, but you have to go register an account and grab a key before they’ll do anything. For a lot of people, “you still have to sign up” already isn’t free of strings.

Fake version two: it flies the “open source” flag, but really means “source-available, no commercial use.” This is the nastiest one, because you can’t tell without opening the LICENSE. Sentry’s official MCP uses the FSL (Functional Source License) — you get to read the source, but “competing use” is forbidden, and it only converts to Apache two years later. More surprising still: Anthropic’s own official document skills (the ones that handle PDF, Word, PPT, Excel) spell it out in the LICENSE in black and white — ”© 2025 Anthropic, all rights reserved” — and the repo’s own README admits it’s “source-available, not open source.” You can read it, you can use it inside Claude, but it isn’t open source; you can’t take it and modify it or redistribute it.

Fake version three: no LICENSE at all. I checked a fairly popular Spotify MCP, and there was simply no license file in the repo — legally, no license means “all rights reserved,” so strictly speaking even using it cleanly is shaky.

None of these three show up if you just glance at the star count or the top of the README. You have to click into each one and check the LICENSE, check whether it calls an external API, check whether it needs an account. That’s exactly what wore me down, so I sat down and checked them one by one.

After checking: the genuinely free and open batch actually holds up well

The good news: by the end, the batch that’s truly MIT/Apache, install-and-go, mostly no account needed turned out to be genuinely high quality. A few I installed the moment I was done checking:

• The official reference servers (modelcontextprotocol/servers, all MIT): filesystem, git, fetch, memory, sequential-thinking, time — they run purely locally, no network, no account, the foundational six-pack for Claude.
• gstack (built by Garry Tan, MIT, 100k+ stars on GitHub): 23 slash commands that organize Claude Code into a “virtual software team” — planning, design, review, QA, and release all chained together.
• ruflo (by ruvnet, MIT, 40k+ stars): one npx ruflo init drops a multi-agent swarm onto Claude Code — 314 MCP tools, self-learning memory, cross-machine collaboration.
• Playwright MCP (Microsoft, Apache), Chrome DevTools MCP (Google, Apache), Context7 (MIT, feeds AI real-time, accurate library docs) — the big-vendor and top-community ones are all genuinely open source.
• On the skills side there’s superpowers, wshobson/agents (30k+ stars), and GSD — all MIT open-source skill collections.

One aside: the few free tools I’ve rebuilt myself follow the same path — Unterm, the terminal, exposes 65 of its methods as MCP so an AI can drive it directly, and SoloMD ships a 1.5 MB MCP server that lets Claude read your local notes library. All MIT, none need an account.

I collected them into a directory: To Be Free

Checking them one by one is exhausting, and keeping the results on my own hard drive helps no one. So I laid them out and turned them into a site — To Be Free: a bilingual, fully static, zero-tracking directory of free tools.

The bar is hard, and all three conditions must be met: genuinely free (core features free forever, not a limited trial), completely ad-free, and no strings (it won’t force you to sign up or track your data). Open source is a bonus, not a requirement — so closed-source but genuinely clean tools like Everything and Obsidian get in too, but whether it’s open source, whether it needs an account, whether it works offline is all labeled with plain badges on every card, so you can judge for yourself.

Beyond the software, I built a dedicated Skills & MCP section and put all the free MCP servers and skills I’d checked into it, each one labeled with its license, which clients it’s compatible with, and a one-click-copy install command. The traps from earlier — the ones needing a key, the FSL ones, the ones with no license — are all filtered out for you at the point of listing.

This is really the next step in my “rebuild 100 free software tools” project: rebuilding them myself isn’t enough. The genuinely free, genuinely clean good stuff deserves a single place to live, instead of being scattered across hundreds of repos waiting for you to dig through every LICENSE yourself.

Further reading

• To Be Free (free software + MCP/skills directory): tobefree.pages.dev/en
• Related on this site: Why I’m Rebuilding 100 Free Software Tools
• Related on this site: I Built Another Terminal, Unterm — Its Default User Isn’t Human