Building chat interfaces in Streamlit. Use when creating conversational UIs, chatbots, or AI assistants. Covers st.chat_message, st.chat_input, message history, and streaming responses.

Builds bidirectional Streamlit Custom Components v2 (CCv2) using `st.components.v2.component`. Use when authoring inline HTML/CSS/JS components or packaged components (manifest `asset_dir`, js/css globs), wiring state/trigger callbacks, theming via `--st-*` CSS variables, or bundling with Vite / `component-template` v2.

Building dashboards in Streamlit. Use when creating KPI displays, metric cards, or data-heavy layouts. Covers borders, cards, responsive layouts, and dashboard composition.

Building multi-page Streamlit apps. Use when creating apps with multiple pages, setting up navigation, or managing state across pages.

Choosing the right Streamlit selection widget. Use when deciding between radio buttons, selectbox, segmented control, pills, or other option selection widgets. Helps pick the right widget for the number of options and selection type.

Build production-grade Streamlit apps. Used when creating, editing, debugging, or deploying Streamlit applications. Routes to specialized sub-skills for performance, layouts, design, data display, and more.

Improving visual design in Streamlit apps. Use when polishing apps with icons, badges, spacing, or text styling. Covers Material icons, badge syntax, divider alternatives, and text casing conventions.

Organizing Streamlit code for maintainability. Use when structuring apps with separate modules and utilities. Covers separation of concerns, keeping UI code clean, and import patterns.

Setting up Python environments for Streamlit apps. Use when creating a new project or managing dependencies. Covers uv for dependency management and running apps.

Documents Streamlit CLI commands for running apps, managing configuration, and diagnostics. Use when starting Streamlit apps, configuring runtime options, or troubleshooting CLI issues.

Structuring Streamlit app layouts. Use when placing content in sidebars, columns, containers, or dialogs. Covers sidebar usage, column limits, horizontal containers, dialogs, and bordered cards.

Covers all Markdown features in Streamlit including GitHub-flavored syntax plus Streamlit extensions like colored text, badges, Material icons, and LaTeX. Use when formatting text, labels, tooltips, or any text-rendering element.

Using st.session_state to manage state across Streamlit reruns. Use when persisting data, handling widget state, implementing callbacks, or debugging state issues. Covers initialization patterns, widget-state association, and common gotchas.