Use Claude's Code Execution tool to run Python in a sandboxed environment as part of a response — for calculation, data analysis, chart generation, and verification. Covers enabling, file upload, persistence across turns, and limitations. Use this skill when building features that need Claude to actually run code (not just write it), such as data analysis, math verification, or chart creation. Activate when: Claude code execution, Python sandbox, run code tool, data analysis agent, code interpreter, code_execution_20250522.
Build browser/desktop automation agents using Claude's Computer Use capability — screen-taking, clicking, typing. Covers the reference container, virtualization safety, task decomposition, and when to use computer-use vs API integration. Use this skill when building agents that operate GUIs (browsers, legacy apps), automating workflows without APIs, or QA/testing agents. Activate when: Claude computer use, browser automation, desktop agent, screen control, computer_20250124, click and type agent.
Use Claude's extended thinking (reasoning) mode effectively — budget tokens, interleaved thinking with tool use, when it helps, when it wastes tokens, and how to inspect the thinking trace. Use this skill when building reasoning-heavy features (math, code generation, multi-step planning), debugging why a model is shallow on hard problems, or deciding whether to enable thinking. Activate when: extended thinking, thinking tokens, budget_tokens, reasoning mode, interleaved thinking, thinking blocks.
Use Claude's 1M-token context window effectively — when to use it, how to structure inputs for recall, how to price it, and how to combine with prompt caching to keep it affordable. Use this skill when building apps that feed large codebases, long documents, or entire conversation histories to Claude, or when weighing 1M context vs RAG. Activate when: 1M context, long context, big context window, context vs RAG, Claude 1 million tokens, context-beta header.
Use Claude's Memory tool to give agents persistent cross-session memory stored in a client-side file directory. Covers setup, directory layout, reading/writing patterns, and when memory beats context-stuffing. Use this skill when building agents that need to remember across sessions (user preferences, project state, past decisions), or when moving from "stuff everything into context" to persistent memory. Activate when: Claude memory tool, agent memory, persistent memory, memory directory, cross-session state, long-term memory agent.
Use Claude's prompt caching with 5-minute and 1-hour TTLs to slash costs on repeated context — codebases, system prompts, long documents. Covers cache breakpoints, hit-rate optimization, and the common mistakes that silently disable caching. Use this skill when building apps with repeated large context, optimizing LLM spend, or debugging "why are my cache reads zero?" Activate when: prompt caching, cache_control, cache hit rate, 5 minute cache, 1 hour TTL cache, ephemeral cache, reduce Claude cost.
Build your first Claude Agent SDK agent — TypeScript or Python. Covers installation, minimal agent loop, tool definitions, and the difference between "roll-your-own" and Managed Agents. Use this skill when starting a new AI agent project, migrating from raw messages.create loops to the Agent SDK, or evaluating SDK vs direct API. Activate when: Claude Agent SDK, @anthropic-ai/claude-agent-sdk, build agent, agent SDK quickstart, agent tutorial.
Stream agent output correctly — text deltas, tool-use events, thinking deltas, progress indicators — without dropping events or blocking on long tool calls. Covers backpressure, error handling, and UX patterns. Use this skill when building agent UIs (chat, CLI), ensuring agents feel responsive, or debugging dropped/truncated streams. Activate when: agent streaming, stream events, text deltas, streaming UI, SSE agent, stream tool use.