ai-cli

name: ai-cli description: >- Use modern, token-efficient command-line tools (fd, ripgrep, ast-grep, bat, sd, jq, yq, tokei, eza, dust, procs, delta, hyperfine, just) instead of legacy coreutils (find, grep, cat, sed, ls, du, ps) for any shell, file, or codebase task — on any platform (Linux/macOS/Windows) and through any executor (a terminal, Claude Code's bash tool, Desktop Commander, or an MCP shell bridge). Trigger whenever you are about to search files, grep for text, read or inspect files, find-and-replace, refactor code, traverse a repository, process JSON/YAML, or inspect disk usage or processes — even if the user did not name a specific tool. These tools are faster, .gitignore-aware, and emit clean structured output that protects the context window. For installation across operating systems and platform-specific quirks, see references/. If you run commands specifically through the LocalREPL MCP bridge, also consult the local-repl-cli skill for environment-specific gotchas.

AI-CLI — Modern Command-Line Tools for Agents

Legacy GNU coreutils (find, grep, cat, sed, ls) were designed for a human at a terminal. They are slow, awkward to compose, and emit output hostile to a language model's context window. This skill maps common shell tasks onto fast, structured-output replacements and defines the invocation rules that keep them predictable for an agent.

This skill is execution-agnostic. The rules below hold whether you run commands in a plain terminal, via Claude Code's bash tool, via Desktop Commander, or through an MCP shell bridge. What does change between environments — $PATH inheritance, which shell /bin/sh points to, pager behavior, GNU-vs-BSD flag differences — is covered in references/cross-platform.md. Read it before debugging anything that "works in my terminal but not here."

Why this matters for an agent

Three failure modes to design against:

1. Context blowout — cat-ing a 10,000-line file dumps the whole thing into context. Read surgically instead.
2. Recursion noise & loops — find descends into node_modules/, .git/, .venv/, producing thousands of irrelevant paths. The modern tools respect .gitignore and skip hidden dirs by default.
3. Tokenization corruption — ANSI color codes shatter clean tokenization. Strip them on every call.

The Golden Rules (every invocation, every platform)

1. No color. Always --color=never / --no-color. Color escapes corrupt tokenization and carry no information for an agent.
2. No pagers, no TUIs. bat (and delta, git) hang waiting on an interactive pager. Always --paging=never. Never invoke interactive modes (-i, fzf, zoxide's zi) — there is no human at the keyboard.
3. Read surgically. Never dump a whole file. Search first, then read a line range around the hit (bat -r 50:120).
4. Prefer structured output. Use --json (ripgrep, ast-grep) and pipe to jq/yq. Parse data structures; don't regex over prose.
5. Stay deterministic and safe. Preview any file mutation before applying (sd -p, ast-grep without --update-all). When chaining steps in bash, use set -euo pipefail — but see cross-platform.md, since /bin/sh may be dash, not bash.
6. Emit absolute paths. Prefer absolute paths (fd -a) so a later step never depends on the current working directory.

Task → Tool quick map

Choosing your search tool: fd vs rg vs ast-grep

• fd — you know something about the filename, path, or type ("find all test_*.py").
• rg — you want text/content anywhere, as a fast first pass. Use -l to get just filenames to feed the next step.
• ast-grep — you care about code structure, not text (refactors; "find every call to foo() regardless of whitespace, comments, or wrapping"). Regex can't see that foo(\n a,\n b) equals foo(a, b); ast-grep can — and it won't clobber a substring inside another name.

Rule of thumb: locate with rg/fd, transform with ast-grep/sd.

Core tools (agent-optimized invocations)

fd — file discovery (replaces find)

.gitignore- and hidden-aware by default; -H includes hidden, -I ignores ignore-files (needed when cleaning gitignored cache dirs). Smart-case.

• fd -a -e py 'test_' — absolute paths, Python files matching test_
• fd -t d -a '__pycache__' — directories only
• fd -e json -x jq '.version' {} — run a command per match (parallel)

ripgrep (rg) — content search (replaces grep)

• rg --color=never 'TODO' — basic recursive search
• rg --json 'fn main' — structured records; pipe to jq
• rg -l 'import torch' — files-with-matches only; feed to the next tool
• rg -t py -C 3 'def train' — Python only, 3 lines of context
• rg -F 'literal[brackets]' — fixed-string mode

ast-grep — structural search & rewrite (replaces grep+sed for code)

• ⚠️ On Linux the command is ast-grep, not sg (sg is setgroups).
• search: ast-grep -p 'console.log($A)' -l js
• rewrite (preview): ast-grep -p 'console.log($A)' -r 'logger.info($A)' -l js
• apply: add -U / --update-all — preview first, then re-run with -U.
• metavariables: $VAR = one node; $$$ARGS = a sequence. ($$$ binds arg lists, not function bodies — def $NAME($$$): $$$ matches nothing.)

bat — surgical file reading (replaces cat)

• ⚠️ Always --paging=never or it hangs on a pager.
• bat --style=plain --paging=never --color=never -r 50:120 file.py
• use --style=numbers when you need line numbers to plan an edit.

sd / jq / yq — replace & structured data

• sd -p 'foo' 'bar' file — preview find/replace; drop -p to apply. For code identifiers use ast-grep instead (sd clobbers substrings).
• jq -r '.items[].name' f.json — raw strings out; jq -c for compact.
• yq '.tools.python' pyproject.toml — yq handles YAML/TOML/JSON/XML.

Extended tools

• tokei — tokei --output json for languages/files/lines. First move when sizing an unfamiliar repo.
• eza — directory listing; the maintained successor to exa (which is abandoned — don't use exa). eza --tree --level=2 --color=never.
• dust — dust -d 1 shows what's eating disk (replaces du).
• procs — procs --no-color python (replaces ps).
• delta — a viewer for git/unified diffs; pipe git diff through it.
• hyperfine — hyperfine --warmup 3 'a' 'b' for rigorous benchmarking.
• just — a command runner (replaces make); just --list, just <recipe>.

Installation & cross-platform

• references/installation.md — install matrix across Linux package managers, macOS (Homebrew), Windows (scoop/winget), and the universal cargo/npm/ pip routes; includes the Debian fd→fdfind / bat→batcat rename trap.
• references/cross-platform.md — OS and shell differences agents trip on: GNU vs BSD/macOS flags, the sg/setgroups clash, $PATH inheritance in spawned subprocesses, /bin/sh-is-dash, and Windows/WSL/PowerShell notes.
• references/cookbook.md — execution-agnostic combined pipelines (orient-in-a-repo, locate→read, safe refactor, rg→jq).
• scripts/check_tools.sh — POSIX self-check (OK/MISSING + install hints). On Windows run it under WSL or Git Bash, or port the loop to PowerShell.

When to use this skill

Trigger when the task involves searching, inspecting, counting, comparing, refactoring, or traversing files/code, or extracting fields from JSON/YAML — even when no specific tool is named. Do NOT trigger for pure in-language work (writing a Python function), single-file edits handled by an edit tool, or questions that don't touch the filesystem.

Running through a specific executor

The tool knowledge here is identical regardless of how shell runs. Only the wrapper differs: Claude Code's bash tool and Desktop Commander's process tools work directly. If you run commands through the LocalREPL MCP bridge, also read the local-repl-cli skill — it documents that environment's specific gotchas (structured run_shell output, /bin/sh not bash, PATH inheritance, ripgrep's stdin-hang, and operational-memory logging).