phosae/mcp-filesystem-server

MCP Filesystem Server

Simple Golang server for learning Model Context Protocol (MCP).

This server provides secure filesystem access to Claude and other MCP clients.

Integrate it with Claude Code

{
./build.sh
DIR=$(pwd)
claude mcp add-json access-fs '{"type":"stdio","command":"'$DIR'/mcp-filesystem-server","args":["-dir", "'$DIR'"]}' --scope user
claude mcp add-json access-fs-sdk '{"type":"stdio","command":"'$DIR'/mcp-filesystem-server-mark3labs-mcp-go","args":["-dir", "'$DIR'"]}' --scope user
}

let Claude Code to use the MCP server to list the file,

claude "use access-fs to list file in ."

The output will similar to

access-fs - list_directory (MCP)(path: ".")
  ⎿  Directory contents:
     .git/
     .gitignore
     … +9 lines (ctrl+r to expand)

⏺ - .git/
  - .gitignore
  - README.md
  - build.sh
  - cmd/
  - go.mod
  - go.sum
  - internal/
  - mcp-filesystem-server
  - mcp-filesystem-server-mark3labs-mcp-go
  - test.sh

Prompts and Cost for this MCP server

Pure Golang Version

Prompt Claude Code

Create an MCP server in Golang to give Claude access to files in specific directory. The MCP server can expose file system access through standardized tools.

mark3labs/mcp-go version and refactor

Prompt for v2: sdk version

1. describe this project
2. add one more command mcp-filesystem-server-mark3labs-mcp-go (the previous is mcp-filesystem-server), implement a new mcp server provides same abilities via sdk github.com/mark3labs/mcp-go
3. rename run.sh to build.sh, use build.sh to build two binaries.

Prompt for as standard Go layout: separate the code of two binaries using Golang's classic cmd dir structure.

Prompt for works in any dir: make mcp servers to works in any directories, not just BaseDir. the directory can be as boot argument.

Prompt: update @test.sh to the latest version

Cost

This learning mcp project costs $4.64.

Total cost:            $4.64 (costs may be inaccurate due to usage of unknown models)
Total duration (API):  24m 19.4s
Total duration (wall): 1h 0m 43.1s
Total code changes:    1310 lines added, 64 lines removed
Usage by model:
claude-3-5-haiku-20241022:  22.4k input, 1.3k output, 0 cache read, 0 cache write
cluade-sonnet-4-20250514:  313 input, 27.6k output, 4.5m cache read, 745.9k cache write