Reference / Built-in filters

Built-in filters

banish ships with filters for the commands agents run all day. They are plain .bsh files embedded into the binary at build time, one per ecosystem.

What ships

Ecosystem	Commands compacted
git	status, diff, log, branch
docker	ps, build, images, compose
kubectl	get, describe, logs
node	npm, yarn, pnpm install and run
rust	cargo build, test, check
go	go build, test, vet
java	maven and gradle builds
python	pytest, pip
cloud	aws, terraform

Each filter targets the noisy, predictable output these tools print and returns just the part the model needs. For worked examples with before-and-after token counts, see the per-command guides: git, cargo, npm, kubectl, and go test.

Directive reference

A .bsh file is a list of directives. These are the ones you will use most:

Directive	Purpose
`!extension`	Names and versions an extension file.
`!verb`	Declares a command shortcut.
`!args`	Names the parameters a verb accepts.
`!expand`	The command a verb expands into.
`!help`	Description shown to the agent.
`!filter`	Declares an output filter.
`!match`	Substring that selects which commands the filter handles.
`!compact`	Shell one-liner that strips the noise from stdout.
`!config`	Opens a block of runtime options.
`!timeout`	Maximum time a command may run.
`!output`	Output format, for example `json`.

Add your own

Create a file in ~/.banish/ext:

!extension mytools v:1.0
 
!filter docker-build
!match docker build
!compact "grep -v '^Sending build' | grep -v '^---> ' | tail -20"

Save it and the filter is live. A new filter is about ten lines, which is why it is the most common first contribution. If a filter fails, banish falls back to raw output, so a work-in-progress filter never breaks anyone.