shorter

shorter is a Bash-wrapper alternative to command output optimizers such as rtk-ai/rtk. RTK uses a Rust proxy plus agent-specific rewrite hooks. This project keeps the setup smaller: install shell wrapper functions, add one uniform flag when output should be compact, and give the agent a preference string telling it when to use that flag.

The filtering itself is RTK-style: command-aware filters run first for high-value commands, then generic line/byte compaction runs as a fallback.

Install

./install.sh

The installer copies:

• bin/shorter to ~/.local/bin/shorter
• shell/shorter.sh to ~/.local/share/shorter/shorter.sh
• a small source snippet into ~/.bashrc or ~/.zshrc

It also installs a shorten compatibility symlink so older shell sessions keep working until they are reloaded.

Useful installer options:

./install.sh --no-rc
./install.sh --shell bash
./install.sh --rc ~/.bashrc
./install.sh --agent-preferences
./install.sh --uninstall

Usage

After installation, the shell wrappers do not change normal command output:

git diff
cat src/app.ts

Add --shorten when you want compact output:

git diff --shorten
cat src/app.ts --shorten
rg "TODO|FIXME" . --shorten
pytest --shorten

The wrapper removes the --shorten flags before running the real command, captures stdout and stderr, applies semantic filters when available, then applies generic compaction:

• compacts git status, git log, git diff, and common git actions
• groups grep/rg matches by file
• groups find/fd results by directory
• trims listing output from ls/tree
• keeps the useful failure/error lines from common test and diagnostic commands
• strips known boilerplate from make, terraform, pre-commit, curl, wget
• collapses repeated identical lines
• collapses long blank runs
• limits output by lines and bytes, preserving the beginning and end
• optionally compacts full-line comments when requested

You can also call the executable directly without shell wrappers:

shorter git status
shorter cat src/app.ts --shorten-comments=compact

Examples

git status

$ git status --shorten
* main
 M src/app.py
?? scratch.txt

git diff

$ git diff --shorten
diff --git a/src/app.py b/src/app.py
--- a/src/app.py
+++ b/src/app.py
@@ -9,3 +9,5 @@ def noisy():
+def dirty_change():
+    return "dirty TODO needle"
summary: 1 file(s), 1 hunk(s), +2 -0

rg / grep

$ rg TODO . --shorten
./README.md
  3: This README has TODO references.
./src/app.py
  7:     # TODO: simplify this helper
  13:     return "dirty TODO needle"
./src/util.ts
  1: // TODO: convert to stricter types
summary: 5 match(es) in 4 file(s)

Test runners

$ npm test --shorten
> vitest run
 FAIL  src/app.test.ts > adds numbers
AssertionError: expected 2 to be 3
 Test Files  1 failed | 2 passed
      Tests  1 failed | 9 passed

$ cargo test --shorten
---- parser::tests::bad stdout ----
thread 'parser::tests::bad' panicked at src/lib.rs:10:5: expected true
test result: FAILED. 2 passed; 1 failed; 0 ignored

Boilerplate-heavy tools

$ terraform plan --shorten
Terraform will perform the following actions:
  # aws_instance.web will be created
  + resource "aws_instance" "web" {}
Plan: 1 to add, 0 to change, 0 to destroy.

$ pre-commit --shorten
Trim Trailing Whitespace.................................................Passed
Check Yaml...............................................................Failed
- hook id: check-yaml
- exit code: 1

RTK Comparison

The table below comes from a deterministic side-by-side fixture using RTK 0.42.0 and shorter 0.1.0. exact means byte-for-byte identical output in that fixture; similar means the same important facts with different formatting.

Command	RTK bytes	shorter bytes	Result
git status	36	36	exact
git diff	176	190	similar
git log -n 3	108	66	similar
read file / cat file	255	255	exact
grep TODO .	244	265	similar
find "*.py" .	39	43	similar
ls -la	50	48	similar
diff file1 file2	474	457	similar
pytest	152	34	similar
npm test	159	159	exact
cargo test	167	167	exact
make	18	18	exact
terraform plan	163	163	exact
pre-commit	204	204	exact

Uniform Flags

These flags work with every wrapped command:

--shorten
--no-shorten
--shorten-lines=N
--shorten-bytes=N
--shorten-comments=keep|compact|strip
--shorten-mode=auto|plain|code|diff|test
--shorten-stats
--shorten-raw

Defaults can be configured with environment variables:

export SHORTER_LINES=120
export SHORTER_BYTES=12000
export SHORTER_COMMENTS=keep
export SHORTER_AUTO=0

Set SHORTER_AUTO=1 if you want installed wrappers to compact output even when the command does not include --shorten.

The old SHORTEN_* environment variables are still accepted as fallbacks, but new configuration should use SHORTER_*.

Shell Wrappers

The default wrapper list is:

cat head tail sed awk grep egrep fgrep rg find fd ls tree git gh glab diff pytest py.test python python3 npm npx pnpm yarn bun jest vitest playwright cargo go make cmake ninja docker docker-compose kubectl helm terraform tofu aws curl wget jq yq ps df du wc env psql ruff mypy eslint tsc prettier next prisma golangci-lint rubocop rspec rake bundle dotnet mvn gradle gradlew shellcheck pre-commit

Override it before sourcing the shell integration:

export SHORTER_ALIAS_COMMANDS="cat rg git pytest"
. ~/.local/share/shorter/shorter.sh
shorter_aliases

Despite the function name, shorter_aliases installs wrapper functions rather than aliases. That preserves native tab completion in zsh: git <TAB> still uses the normal git completion while git status --shorten still routes through shorter. In bash, shorter and the old shorten compatibility command get basic command-name completion; existing per-command completions generally stay attached to the original command names.

Agent Preference String

Print the preference string with:

shorter --agent-preferences

Current string:

When shell command output is likely to be noisy, prefer the installed shorter wrappers and add the uniform `--shorten` flag to the command. Examples: `git status --shorten`, `git diff --shorten`, `rg "pattern" . --shorten`, `pytest --shorten`, `npm test --shorten`, `terraform plan --shorten`. If wrappers are not loaded in the current shell, call `shorter <command> ...` instead, for example `shorter git diff`. The wrapper removes `--shorten` before running the real command, applies RTK-style command-aware filters when available, then falls back to generic line/byte compaction. Use `--shorten-lines=N` or `--shorten-bytes=N` for tighter limits. Use `--shorten-comments=compact` when reading source files where comments are not important. Use `--shorten-raw` to skip semantic filters but keep generic limits. If exact raw output is required, omit `--shorten` or add `--no-shorten`.

Put that in whichever agent preference file or settings UI you use.

Limits

The wrapper captures stdout and stderr together before filtering, so it is best for agent-facing command output rather than interactive commands. If a real command needs to receive an argument named --shorten, place it after a literal --.

This is not a line-for-line port of RTK internals. It intentionally keeps the shell wrapper model and implements the same categories of behavior with portable Bash/awk filters.