head

Files

SKILL.mdagentsreferencesscripts

Install

Install only this skill with npx skills

npx skills add alisonaquinas/llm-shared-skills --skill 'head' -g -y

Install the containing skill bundle

/plugin install shared-skills@llm-skills

Download head-skill.zip

This skill is bundled inside shared-skills. Use npx skills when you only want this skill, or install the bundle once to make every included skill available through the plugin marketplace flow. Browse the full skill bundle repository at github.com/alisonaquinas/llm-shared-skills.

Invoke

Invoke this skill after installation

/shared-skills:head

SKILL.md

name: head description: Quickly sample the beginning of files with head for inspecting headers, previewing content, and validating file prefixes. Use when the agent needs to peek at file starts, limit output to N lines or bytes, or validate file format headers.

Sample and display the first lines or bytes of files or streams.

Quick Start

Verify head is available: head --version or man head
Establish the command surface: man head or head --help
Start with a read-only probe: head -n 5 file.txt

Intent Router

Load only the reference file needed for the active request.

references/install-and-setup.md — Installing head (GNU, BSD) on macOS, Linux, Windows
references/cheatsheet.md — Common flags, line/byte counts, multiple files, quiet/verbose output
references/advanced-usage.md — GNU vs BSD differences, large file handling, stream processing, performance
references/troubleshooting.md — Encoding issues, binary files, empty output, permission errors

Core Workflow

Verify head version and variant (GNU vs BSD): head --version or man head
Specify count explicitly: -n <N> for lines or -c <N> for bytes
Use -q (quiet) for multiple files to suppress file headers
Run on sample data first to validate before processing at scale

Quick Command Reference

head --version                      # Check version (GNU vs BSD)
head -n 5 file.txt                 # First 5 lines (explicit count)
head -c 1024 file.bin              # First 1024 bytes (explicit count)
head -n -5 file.txt                # All lines except last 5 (GNU only)
head -q -n 2 *.log                 # First 2 lines from all files, no headers
head -v -n 3 file.txt              # First 3 lines with file header (verbose)
man head                            # Full manual and options

Safety Notes

Area	Guardrail
Explicit counts	Always use `-n` or `-c` with explicit numbers; default values (10 lines) may not match intent.
Multiple files	When reading multiple files with `-q`, output lacks file name markers; confirm context before processing.
Binary files	head on binary files may include non-text bytes. Pipe through `xxd` or `od` for safe hex viewing.
GNU vs BSD	GNU head supports `-n -5` (all except last 5); BSD does not. Avoid for portability or test on target platform.
Incomplete lines	When using `-c`, output may end mid-line; subsequent processing may fail if expecting complete records.
Large files	head terminates early (safe) but still reads through file sequentially; not suitable for random access to large files.

Source Policy

Treat the installed head behavior and man head as runtime truth.
Use GNU Coreutils documentation (gnu.org/software/coreutils) for GNU-specific extensions.
Use BSD manual for BSD variant behavior differences.

Resource Index

scripts/install.sh — Install head (GNU, BSD, or POSIX variant) on macOS or Linux.
scripts/install.ps1 — Install head on Windows or any platform via PowerShell.