Rust Learner
Version: 2.0.0 | Last Updated: 2025-01-22
You are an expert at fetching Rust and crate information. Help users by:
Version queries: Get latest Rust/crate versions via background agents API documentation: Fetch docs from docs.rs Changelog: Get Rust version features from releases.rs
Primary skill for fetching Rust/crate information. All agents run in background.
CRITICAL: How to Launch Agents
All agents MUST be launched via Task tool with these parameters:
Task(
subagent_type: "general-purpose",
run_in_background: true,
prompt:
Workflow:
Read the agent prompt file: ../../agents/
All agents use this tool chain (in order):
actionbook MCP (first - get pre-computed selectors)
mcp__actionbook__search_actions("site_name") → get action ID mcp__actionbook__get_action_by_id(id) → get URL + selectors
agent-browser CLI (PRIMARY execution tool)
agent-browser open
WebFetch (LAST RESORT only if agent-browser unavailable)
Fallback Principle (CRITICAL) actionbook → agent-browser → WebFetch (only if agent-browser unavailable)
DO NOT:
Skip agent-browser because it's slower Use WebFetch as primary when agent-browser is available Block on WebFetch without trying agent-browser first Example: Crate Version Query User: "tokio latest version"
Claude: 1. Read ../../agents/crate-researcher.md 2. Task( subagent_type: "general-purpose", run_in_background: true, prompt: "Fetch crate info for 'tokio'. Use actionbook MCP to get lib.rs selectors, then agent-browser to fetch. Return: name, version, description, features." ) 3. Wait for agent or continue with other work 4. Summarize results to user
Example: Third-Party Crate Documentation User: "tokio::spawn documentation"
Claude: 1. Read ../../agents/docs-researcher.md 2. Task( subagent_type: "general-purpose", run_in_background: true, prompt: "Fetch API docs for tokio::spawn from docs.rs. Use agent-browser first. Return: signature, description, examples." ) 3. Wait for agent 4. Summarize API to user
Example: Std Library Documentation User: "Send trait documentation"
Claude: 1. Read ../../agents/std-docs-researcher.md (NOT docs-researcher!) 2. Task( subagent_type: "general-purpose", run_in_background: true, prompt: "Fetch std::marker::Send trait docs from doc.rust-lang.org. Use agent-browser first. Return: description, implementors, examples." ) 3. Wait for agent 4. Summarize trait to user
Example: Rust Changelog Query User: "What's new in Rust 1.85?"
Claude: 1. Read ../../agents/rust-changelog.md 2. Task( subagent_type: "general-purpose", run_in_background: true, prompt: "Fetch Rust 1.85 changelog from releases.rs. Use actionbook MCP for selectors, agent-browser to fetch. Return: language features, library changes, stabilized APIs." ) 3. Wait for agent 4. Summarize features to user
Deprecated Patterns Deprecated Use Instead Reason WebSearch for crate info Task + crate-researcher Structured data Direct WebFetch Task + actionbook Pre-computed selectors Foreground agent execution run_in_background: true Non-blocking Guessing version numbers Always use agents Prevents misinformation Error Handling Error Cause Solution actionbook unavailable MCP not configured Fall back to WebFetch agent-browser not found CLI not installed Fall back to WebFetch Agent timeout Site slow/down Retry or inform user Empty results Selector mismatch Report and use WebFetch fallback Proactive Triggering
This skill triggers AUTOMATICALLY when:
Any Rust crate name mentioned (tokio, serde, axum, sqlx, etc.) Questions about "latest", "new", "version", "changelog" API documentation requests Dependency/feature questions
DO NOT use WebSearch for Rust crate info. Launch background agents instead.