MCP servers / Compared
MCP servers compared: which need an API key, and which can change things
14 MCP servers side by side. Every number here comes from the tool list the server itself reported when we started it on 2026-09-20, so it matches the individual server pages. "Can change things" means the tool declares that it is not read-only. It does not mean the tool is dangerous, only that it can act.
MCP servers that need no API key
Filesystem, Git, Context7, Playwright, Chrome DevTools, Fetch, Memory, Sequential Thinking, Time.
These need no account. Most only need Node.js or Python tooling installed.
MCP servers that need an API key or token
- GitHub:
GITHUB_PERSONAL_ACCESS_TOKEN - Firecrawl:
FIRECRAWL_API_KEY - Brave Search:
BRAVE_API_KEY - Tavily:
TAVILY_API_KEY - Notion:
NOTION_TOKEN
Keep these out of your config file by referencing an environment variable. See keeping API keys out of your MCP config.
Servers where no tool can change anything
Context7, Brave Search, Tavily, Sequential Thinking, Time.
Brave Search, Tavily do not declare read-only hints, so we judged them by name: every tool searches and returns results. Context7, Brave Search, Tavily send your queries to an outside service, so "cannot change anything" is not the same as "private".
Servers with the most tools that can change things
- Chrome DevTools: 22 of 29 tools (76%)
- Playwright: 18 of 25 tools (72%)
- Memory: 6 of 9 tools (67%)
- Notion: 10 of 24 tools (42%)
- Git: 5 of 12 tools (42%)
- Firecrawl: 11 of 27 tools (41%)
- Filesystem: 4 of 14 tools (29%)
Fetch does not declare whether its tool is read-only, so it is not counted above. GitHub is not measured because it runs in Docker, which we could not run here. Its README lists toolsets instead, and it has a read-only mode.
The full table
| Server | API key | Runs with | Tools | Can change things | Basis |
|---|---|---|---|---|---|
| Filesystem | No | npx | 14 | 4 | declared |
| Git | No | uvx | 12 | 5 | declared |
| GitHub | Yes | Docker | 22 toolsets | ? | ? |
| Context7 | No | npx | 2 | 0 | declared |
| Playwright | No | npx | 25 | 18 | declared |
| Chrome DevTools | No | npx | 29 | 22 | declared |
| Fetch | No | uvx | 1 | 0 | 1 not declared |
| Firecrawl | Yes | npx | 27 | 11 | declared |
| Brave Search | Yes | npx | 8 | 0 | by name |
| Tavily | Yes | npx | 5 | 0 | by name |
| Notion | Yes | npx | 24 | 10 | by name |
| Memory | No | npx | 9 | 6 | declared |
| Sequential Thinking | No | npx | 1 | 0 | declared |
| Time | No | uvx | 2 | 0 | declared |
How to use this
- Start with fewer tools, not more. Every server you add is code that runs on your machine and tools your AI can call. See the servers worth installing first.
- Limit what a tool can do. Some servers can be restricted (a read-only mode, or a list of enabled tools). Each server page says what we tested.
- Ask your AI. This data is also available as a free MCP server.