Snip: Open-source tool reduces Claude Code token usage with YAML filters

Snip is an open-source tool written in Go that reduces Claude Code token usage by 60-90% by filtering shell command output before it reaches the context window. Inspired by rtk (Rust Token Killer), it takes a different approach: filters are data (YAML files) rather than compiled code.

How it works

AI coding agents often waste tokens on verbose shell output. For example, a passing go test can produce hundreds of lines that the LLM doesn't need, and git log dumps full metadata when a one-liner would suffice. Snip sits between Claude Code and the shell, filtering output through declarative YAML pipelines.

Benchmark example from the source:

• Before: go test ./... → 689 tokens
• After: "10 passed, 0 failed" → 16 tokens (97.7% reduction)

Setup and usage

Setup requires one command:

brew install edouard-claude/tap/snip
snip init

After this, every shell command Claude runs goes through snip.

Key differentiators from rtk

• Filters are YAML files you drop in a folder, not Rust code compiled into the binary
• 16 composable pipeline actions including: keep/remove lines, regex, JSON extract, state machine, group_by, dedup
• Users can write their own filter in 5 minutes without touching Go
• The engine and filters evolve independently

Compatibility

Snip also works with Cursor, Copilot, Gemini CLI, Aider, Windsurf, and Cline.