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Zipping and unzipping archives from an assistant, and what the guards do

Two MCP servers do this and they are easy to confuse, because they have the same name. A blind search recorded here on 2026-09-10 named zip-mcp by loscolmebrothers and zip-mcp by 7gugu, different authors, different repositories, both widely mirrored.

Start with the practical recommendation. loscolmebrothers publishes to npm, so npx -y @loscolmebrothers/zip-mcp starts a server right now, it handles compress, decompress and inspect, and it does password-protected archives, which nothing here does. If you want a zip tool in your client this afternoon and you need passwords, that is the one.

The part nobody writes about, which is the unpacking

Creating an archive is easy. Unpacking one that arrived from outside is where the interesting failures live, and an assistant unpacking a file on your behalf is exactly the case that deserves guards.

Three things can go wrong. A path inside the archive can point outside the directory you are extracting into, using .. segments or an absolute path, and overwrite something it should not. An entry can be a symbolic link that points at a file elsewhere on your disk. And an archive can be small on disk and enormous when expanded, which exhausts memory or fills the volume.

The zip server here refuses all three, and the compression ceiling is set at 100 times rather than a tighter number for a measured reason: real files, particularly logs and CSV exports, legitimately compress past 50 times, so a 50x ceiling refuses honest archives. The measurement behind that is on the zip server's page.

The server here

It registers 7 tools over stdio, plus the two shared licence tools: zip_create, zip_list, zip_extract, zip_add, zip_extract_text, zip_bundle_month, zip_history.

zip_extract_text is the one people do not expect. It pulls the text out of the files inside an archive without unpacking them onto your disk, so you can ask what is in a zip somebody sent you before you decide to trust it. zip_bundle_month collects a month of paperwork from the other servers here into one archive, which is the actual reason this server exists.

It runs on fflate rather than a hand-written zip writer, and it is pure JavaScript, so there is no native module to compile and no system zip binary to find.

One click, no JSON. Download zip.mcpb from the latest release and open it in Claude Desktop. It runs on the Node runtime Claude Desktop ships with, so your own PATH and node version never come into it.

Or a URL, with nothing installed. /mcp/connect mints a free anonymous token and prints the ready line:

claude mcp add --transport http zip https://mcp.zovo.one/mcp/zip/t/<token>

Or from a clone, for a client with no bundle installer. Build once, then point the client at the built file:

git clone https://github.com/theluckystrike/mcp-servers.git
cd mcp-servers && npm install
npm run build -w packages/mcp-license -w servers/zip

claude mcp add --scope user zip -- node /absolute/path/to/mcp-servers/servers/zip/dist/index.js

Claude Desktop, Cursor, Windsurf and Cline take the same two strings as JSON, in claude_desktop_config.json or the client's own MCP config file:

{
  "mcpServers": {
    "zip": {
      "command": "node",
      "args": ["/absolute/path/to/mcp-servers/servers/zip/dist/index.js"]
    }
  }
}

The npm packages are not published yet, so the npx form below returns a 404 today. It is kept because it is what that config becomes the day the publish lands, with nothing else changed; installing these servers when npx does not work yet has the whole picture.

claude mcp add zip -- npx -y @theluckystrike/mcp-zip

The hosted endpoint has three more tools than the stdio build, for uploading a file to it and fetching one back, because a server running on somebody else's machine cannot reach your disk. A tools/list against https://mcp.zovo.one/mcp/zip on 2026-09-10 returned 12 tools against the 9 the local build has.

Free tier and price

Free tier, verbatim from data/facts.json: 20 archives per calendar month, up to 25 MB and 200 entries each, and unlimited reading: zip_list, zip_extract and zip_extract_text are never metered, along with every bomb, traversal and symlink guard.

Reading is never metered, and neither are the guards. Pro is $19 once or $39 for all 33 servers.

What it cannot do

No passwords. It neither creates an encrypted archive nor opens one, which is where the loscolmebrothers server is straightforwardly better.
Zip only. No tar, no gzip on its own, no 7z, no rar.
The free tier caps an archive at 25 MB and 200 entries. A photo library is not the use case.
It will not fetch an archive from a URL. The file has to be on your disk for the local build, or uploaded for the hosted one.
The npm package is not published, so npx does not start it. The bundle, a clone or the hosted URL are the working paths today.

Questions

Which zip MCP server should I install?

If you need password-protected archives or you want an npx one-liner today, zip-mcp by loscolmebrothers. If you want the extraction guards and the ability to read text out of an archive without unpacking it, use this one.

What does the bomb guard actually check?

The ratio of expanded bytes to archive bytes, with a ceiling of 100 times. That number was chosen from measurement rather than convention: real log and CSV archives compress past 50 times, so a tighter ceiling refuses honest files.

Can I look inside an archive without extracting it?

Yes, and it is free on every tier. zip_list gives you the entries and zip_extract_text pulls text content out without writing anything to disk.

Does it handle tar or 7z?

No. Zip only, with no tar, gzip, 7z or rar support and none planned, because the archives this catalogue produces are zip.

Why does the hosted version have more tools?

Because a server running elsewhere cannot read your disk. Three upload and download tools exist only in the hosted build, which is why a tools/list against the endpoint returns more than the local server registers.

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