We launched here last Monday. One number from our prep keeps coming up in conversations, so a question.
We ran every stable version of 14 of the top 30 npm MCP servers from March to September in a throwaway environment, tools/list only. 86 version-to-version transitions. 40 of them changed what the tools do or accept, 47%. The largest category was not added tools. It was rewritten parameter descriptions, 92 of them. The agent reads that text and acts on it. The person approved the server once and never reads it again.
mcpgawk sits on that gap: baseline at approval, refuse the call when the surface changes until a human looks. https://mcp.gawk.dev/ph if you want to try it.
So: when you add an MCP server to Claude Code, Cursor or Codex, what do you do at its next version? Pin it, re-read the tools, or trust the update?
Hey Product Hunt 👋
I built mcpgawk because approving an MCP server is a one-time yes to something that keeps changing. On my own machine, one approved server changed six times in six releases and went from 85 tools to 103. My agent would have called every new one without a second look.
mcpgawk is a free, local checkpoint between your coding agent and the MCP servers it calls.
Today you can:
• See every MCP server your agents can reach, across Claude Code, Cursor, Codex and more
• Approve a server and record exactly what its tools said
• Have a call refused once a tool rewrites its description or gains power you never approved, until you decide
• See what changed (description, inputs or safety flags), old and new side by side
• Rely on your agent not approving it for you: approval is refused inside an agent session
One thing I care about: it all runs on your machine. No account, nothing uploaded.
The CLI and VS Code extension are free; the team gateway is £29/month with a 7-day trial.
If you run more than a couple of MCP servers: how do you find out today when one of them changes?
I'll be here all day answering questions.
Looks promising, I have a group of folks who will be happy seeing this!
@laxman_karthik Thanks Laxman..
Please do pass it on. What's the group working on?
I'd love to hear what they run into with MCP.