FitFileSize runs on your own machine — the client starts it, so there is no endpoint to ping. 86 installs a week from npm. Last commit 28 Oct 2026.
Compress PDFs and images, iPhone HEIC too, to fit an upload limit or a form's rules.
What the code does
We read the source, 5 d ago · rules 995398eba69f
What this server is able to do. For an MCP server this is often the job itself — a terminal server runs commands because that is what it is for. Listed so you know what you are plugging in, not as an accusation.
proc = subprocess.run(args, capture_output=True, timeout=timeout, check=False)
<script
defer
src="https://d1fspum1n48e1s.cloudfront.net/cairn.js"
Is this your server and something here is wrong? Tell us — corrections are free and do not require a plan.
This code can reach further than it looks
We found places where it runs commands, builds paths or queries from values it is given. None of that is a flaw by itself — it becomes one when the code changes, and code changes quietly between releases. We re-read it on every one.
Connect this server
This server runs on your own machine — install it with the package manager and the client starts it for you. Package name taken from the official registry entry.
claude mcp add fitfilesize -- npx -y fitfilesize-mcp{
"mcpServers": {
"fitfilesize": {
"command": "npx",
"args": [
"-y",
"fitfilesize-mcp"
]
}
}
}[mcp_servers.fitfilesize]
command = "npx"
args = ["-y", "fitfilesize-mcp"]{
"mcpServers": {
"fitfilesize": {
"command": "npx",
"args": [
"-y",
"fitfilesize-mcp"
]
}
}
}{
"servers": {
"fitfilesize": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"fitfilesize-mcp"
]
}
}
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FitFileSize — questions
Answers built from our own checks of this server.