Design and review principles for fluid, gestural, physically-responsive interfaces, distilled from Apple's WWDC 2018 "Designing Fluid Interfaces" talk (the iPhone X gestural UI team). Use when designing or reviewing touch/gesture interactions, spring-based motion, drag-to-dismiss or swipe gestures, scroll physics, elastic/ rubberband behaviors, redirectable animations, or when something "feels off", "feels janky", "doesn't feel native", or needs to "feel more fluid/natural/alive". Covers response latency, interruptibility, spatial consistency, gesture hinting, momentum projection, one-to-one touch tracking, and springs vs timed animations. Not for static visual design (color/typography/layout) — pair with make-interfaces-feel-better or 12-principles-of-animation for that.
Search, list, and resume AI agent sessions across Claude Code, Codex CLI, Gemini CLI, opencode, Hermes Agent, and Cline CLI. Use when the user asks to find a past conversation, search session history, resume a previous session, list recent agent activity, or check what was discussed in a prior session. Also use when asked to "find that conversation where I...", "resume my last codex session", "read latest convo", "read last messages", "what did I work on yesterday", "search my claude history for X", or gives an agent session id such as `ses_...`, a UUID, or a Cline id like `1782988565588_qqrxi`.
Cinema 4D MCP expert for extracting scene data, writing C4D Python scripts, and controlling Cinema 4D through MCP tools. Activate when: (1) using cinema4d MCP tools (get_scene_info, list_objects, execute_python_script, add_primitive, etc.), (2) writing Python scripts for Cinema 4D extraction or manipulation, (3) working with MoGraph cloners/effectors/fields, (4) baking animation data from C4D scenes, (5) debugging C4D Python API errors, (6) extracting Redshift material or camera data. Covers critical gotchas, correct extraction patterns, MoGraph baking, timeline evaluation, API compatibility, and known failure modes.
Reverse-engineer minified or obfuscated JavaScript bundles. Primary tool: humanify (humanifyjs) — uses an LLM to rename mangled identifiers back to meaningful names. Default model: gemini-3.1-flash-lite-preview. Use when the user says 'deobfuscate this bundle', 'humanify this', 'rename minified vars', 'reverse engineer this JS', 'what does bundle.js do', or is working in a project with a deobfuscated `og/` or `modules/` folder fed by humanify. Covers humanify CLI invocation, the pseudo-TTY workaround for cursorTo crashes, single-module extraction from a bundle, and chaining with beautifiers.
Automatically research and reverse-engineer a technique, visual effect, algorithm, or codebase. Given a reference (image, video, URL, library name, description, or existing code), Claude researches how it works, reverse-engineers the approach, and produces a structured findings document. Use when you want to understand "how is this made", "reverse engineer this effect", "research this technique", or "figure out how X works so I can implement it".
Distills everything Claude has learned in the current conversation into a structured Markdown knowledge document saved to disk. Use when the user wants to capture findings, decisions, architecture insights, or research from a session — phrases like "document what you know", "save your knowledge", "write up what we found", or "document this".
Appends a thought, instruction, or note to the nearest CLAUDE.md in the current project. Use when the user wants to record a preference, rule, or context for future Claude sessions — phrases like "add this to claude.md", "remember this for next time", "note to claude", or "update claude.md".
Extracts highlights, annotations, and book data from Apple Books via MCP. Use when: user asks to export book highlights, extract annotations with colors, search highlights across books, create highlight summaries, or match books from a reading list against their Apple Books library. Covers efficient batch color extraction (5 calls instead of 150+), annotation-to-book matching, and markdown export patterns.