linesmith

A Rust status line for Claude Code and other AI coding CLIs. Fast cold start, real plugin API, role-based themes, and correctness-first handling of context, rate limits, and worktrees.

Status: bootstrap phase. Docs and tooling foundation complete; Rust scaffold and v0.1 pending.

Why

Existing Claude Code status line tools have real gaps:

Trust and resources. npx -y @latest auto-executes unreviewed code and can spawn 30+ Node processes at 3GB RAM under rapid use.
Correctness. Context %, rate limits, and worktree state all break in common edge cases (1M context, /compact, /resume, 429s, parallel worktrees).
No plugin API. Every existing tool hardcodes its widgets. Custom segments require forking.
No curated onboarding. Users repeatedly ask for "copy a preset and go."

linesmith is built to close those gaps.

Design in one paragraph

A single static Rust binary (~3-5MB, <20ms cold start) reads Claude Code's status line JSON on stdin and renders a composable line with a rich segment system: priority, width hints, conditional visibility, caching, async, and sub-composition. User extensions are written in rhai and loaded from a config directory. Themes are role-based (Catppuccin-compatible). The input schema is tool-agnostic; it works with Claude Code and Qwen Code today, with Codex CLI and GitHub Copilot CLI ready to slot in when they ship compatible APIs.

See docs/adrs/ for the decision rationale behind each piece and docs/research/ for the research that drove those decisions.

Install

Not yet — v0.1 has not shipped. Once it does, install will be one of:

# macOS / Linux
curl -sSf https://linesmith.sh/install.sh | sh

# Homebrew (macOS, Linux)
brew install oakoss/linesmith/linesmith

# Windows PowerShell
powershell -c "irm https://linesmith.sh/install.ps1 | iex"

# Rust users
cargo install linesmith

Distribution is handled by cargo-dist.

Configure (planned)

Wire linesmith into Claude Code's ~/.claude/settings.json:

{
  "statusLine": {
    "type": "command",
    "command": "linesmith",
    "padding": 0
  }
}

linesmith reads its own config from ~/.config/linesmith/config.toml:

theme = "catppuccin-mocha"

[line]
segments = [
  "model",
  "workspace",      # directory/worktree hybrid
  "git_branch",
  "context_window",
  "cost",
  "rate_limit",
]

[segments.context_window]
style = "bar"
width = 10

Drop a .rhai file in ~/.config/linesmith/segments/ to add a custom segment.

Documentation

Folder	Contents
`docs/research/`	Surveys and deep dives (API contract, competitor landscape, user demand, Rust crate survey, cross-tool support)
`docs/adrs/`	Architecture Decision Records (MADR v4.0) — why Rust, why rhai, how segments compose, theming model, schema, distribution
`docs/specs/`	Implementation contracts (written as features are built)
`docs/ideas/`	Exploratory notes
`AGENTS.md`	Instructions for AI coding agents working on this project

See docs/README.md for the full pipeline: how research flows to ideas to ADRs to specs to tasks.

Development

Managed by mise:

mise install              # install all tools (rust, node, prettier, markdownlint, lefthook, cog)
lefthook install          # install git hooks (pre-commit fmt/lint, commit-msg conventional)
mise run check            # run all checks (fmt + lint + Rust)
mise run test             # run all tests

Commit style: Conventional Commits enforced by cog.

License

MIT. The core stays open source; any future plugin ecosystem can ship under any license.

linesmith 0.1.0