Fedit MCP server

fedit — Fast File Editor for the Terminal

A zero-dependency CLI tool for surgical file edits from the command line. No interactive editors. No sed/awk gymnastics. Just simple, predictable operations with built-in verification.

Built for sysadmins, DevOps engineers, and anyone who scripts config changes.

go install github.com/amalexico/fedit@latest

Why fedit?

• One binary, zero dependencies — pure Go, runs everywhere
• 17 language mappers — see the structure of any file before editing
• -v flag — verify every mutation before moving on
• Line-aware — no regex surprises, no "which match did it hit?"
• Stream engine — process multi-GB files line-by-line with atomic integrity
• Field extraction — pull CSV/TSV column N without awk
• Safe — no in-place unless you say so, never touches files you did not name

Install

Go install (recommended):

go install github.com/amalexico/fedit@latest

Or download the binary from GitHub Releases and put it in your PATH.

Verify:

fedit -file /etc/hostname -op show

Quick Start

# See what is in a file
fedit -file config.yaml -op show

# See just lines 10-25
fedit -file config.yaml -op show -line 10 -end 25

# Find every line containing "timeout"
fedit -file config.yaml -op find -match "timeout"

# See the structure of a Go file
fedit -file main.go -op map -lang go

# Replace line 42 with new content
fedit -file config.yaml -op replace -line 42 -end 42 -text "timeout: 60s" -v

# Insert a line after every occurrence of "server {"
fedit -file nginx.conf -op insertafter -match "server {" -text "    include security.conf;" -v

# Move a function block before another (content-matched, atomic)
fedit -file main.go -op move -match "func OldHelper(" -end 45 -beforematch "func NewHelper(" -v

# Copy a config block and paste it 3 times at a new location
fedit -file values.yaml -op copy -line 50 -end 65 -after 200 -times 3 -v

# Extract column 2 from a TSV file (v1.4+)
fedit -file data.tsv -op fields -col 2

# Write content with literal backslashes — no \n escape expansion (v1.6.0)
fedit -file config.txt -op writeraw -text "path=C:\\Users\\admin"

# Hex-encode tricky text to sidestep shell quoting (v1.6.0)
# fwencode produces the hex; fedit decodes it before writing
fe

All Operations

show — Display file contents

# Entire file
fedit -file app.conf -op show

# Lines 50-75 only
fedit -file app.conf -op show -line 50 -end 75
# Last 10 lines
fedit -file app.conf -op show -line -10:

# Lines 50 to 5th from end
fedit -file app.conf -op show -line 50 -end -5

# Lines 100-103 (relative range)
fedit -file app.conf -op show -line 100:+3

# Show from one anchor to another (no line numbers needed)
fedit -file config.go -op show -match "func Start" -endmatch "func End"

find — Search for lines matching a substring

# Find all lines containing "ERROR"
fedit -file /var/log/app.log -op find -match "ERROR"

# Output includes context lines and occurrence numbers
# Use -nth to target a specific match in other operations

Pro tip: Run find first to get line numbers, then use replace or delete with exact lines.

Shortened. The full README is on GitHub.