> ## Documentation Index
> Fetch the complete documentation index at: https://docs.otter-shell.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Tool modules

> Per-tool pure-Zig modules in otter-tools-core.

No UI in this crate. Each module parses, searches, or formats; apps wire results into Surface Description or stdout.

## Calculator (`calc`)

Expression parsing and evaluation for `otter-calc` and launcher `=EXPR` mode. Integer and float paths with bounded token buffers.

## Emoji (`emoji`)

Emoji name search and `:query` completion data shared by `otter-emoji` and launcher.

## Clipboard (`clipboard`, `clip_history`)

History store bounds and `wl-copy`/`wl-paste` compatible invocation. `clip_history` persists entries under XDG data paths via `otter-utils` helpers.

## Calendar (`calendar`)

Month grid generation and weekday headers for `otter-cal`.

## Duration (`duration`)

Human-readable duration parsing (`5m`, `1h30s`) for `otter-timer`.

## Weather (`weather`)

URL construction and response field extraction for `otter-weather`. No HTTP client here; apps fetch.

## Color (`color`)

RGB/HSL/hex conversion for `otter-pick` and launcher color preview.

## Record (`record`)

Encoder and container selection helpers for `otter-rec` (bounded list of installed tools).

## Config (`config`)

Shared key paths and load helpers for tools that read small `.conf` fragments.

## App configs

`app_configs.zig` defines structs for calc, emoji, clip, cal, timer, weather, pick, rec, shot, and related tools. Import from `otter_tools_core.app_configs` in both the app and `otter-settings`.