KitLib serves mod authors and players: test runs, in-run editing, logs, and multiplayer debugging without leaving the game — plus a better Mod panel, progress protection, and feedback export. Core loads optional satellite modules; a failed optional module should not break KitLib or mods that depend on it.
KITLIB
Modular in-game toolkit & extension APIs for Slay the Spire 2
In-game toolkit for Slay the Spire 2
Overview
Install & modules
Install from Steam Workshop or Nexus. In Mods → KitLib → Modules, toggle optional satellites or toggle satellite modules (restart required). See /guide/install/
Dev rail & Dev Mode
In-run rail: browsers, cheats, saves, presets, logs, AI, hooks, scripts. Title Dev Mode: test runs, pseudo co-op, diagnostics. Also: browser dev viewer, mod feedback ZIP, progress guard, MCP. See /guide/panels/ and /guide/title-dev-mode/
For mod developers
Add eng/KitLib.ContentMod.props to your csproj; depend on KitLib modules at runtime as needed. Register rail tabs, logging, and AI hooks. See /developer/extending/panel-registry/ and /developer/dev/