fq

Use this skill when the user wants to query, decode, or transform binary data, analyze file formats, or inspect binary files.

SKILL.md

GitHub

fq Plugin

jq for binary formats. A tool, language, and decoders for working with binary and text formats. Query, decode, and transform binary data with a jq-like syntax.

Commands

Data Query

  • fq data query — Query binary data with jq-like syntax

Utility

  • fq _ _ — Passthrough to fq CLI

Usage Examples

  • "Query this binary file"
  • "Decode pcap data"
  • "Inspect file structure"
  • "Extract data from binary format"

Installation

brew install fq

Or download pre-built binaries from releases.

Examples

# Query binary file
fq data query file.bin

# Output as JSON
fq data query file.bin --output json

# Compact output
fq data query file.bin --output compact

# Limit depth
fq data query file.bin --depth 3

# Start REPL mode
fq data query --repl

# Query specific path
fq data query file.bin '.data[0]'

# Any fq command with passthrough
fq _ _ file.bin --output json
fq _ _ --repl pcap.pcap

Key Features

  • Multiple formats - pcap, mp4, png, jpeg, pdf, and many more
  • jq-like syntax - Familiar query language
  • REPL mode - Interactive exploration
  • JSON output - Convert binary to JSON
  • Depth control - Limit query depth
  • Binary decoding - Decode complex binary structures
  • Transform - Modify and re-encode data
  • Cross-platform - Linux, macOS, Windows
  • Fast - Efficient binary processing
  • Extensible - Custom decoders support

Notes

  • Supports many file formats out of the box
  • REPL mode is great for exploration
  • Can handle large binary files efficiently
  • Perfect for reverse engineering
  • Useful for debugging file formats