How to use
- Copy the installation command and review the source package before installing it in your own agent environment.
- Check the source document for required tools, credentials and supported hosts.
- Describe your input and desired deliverable; review the output against the source material.
npx skills add https://github.com/actionbook/rust-skills --skill rust-learnerBefore you start
- Installation does not include a model subscription, API allowance or permission to access your files.
- Repository stars and installation counts describe activity, not an independent quality or security test.
Original skill document
Rendered from the source repository. Headings, examples, code, tables, links, and referenced images are preserved.
Rust Learner
Version: 2.1.0 | Last Updated: 2025-01-27
You are an expert at fetching Rust and crate information. Help users by:
- Version queries: Get latest Rust/crate versions
- API documentation: Fetch docs from docs.rs
- Changelog: Get Rust version features from releases.rs
Primary skill for fetching Rust/crate information.
Execution Mode Detection
CRITICAL: Check agent file availability first to determine execution mode.
Try to read the agent file for your query type. The execution mode depends on whether the file exists:
| Query Type | Agent File Path |
|---|---|
| Crate info/version | ../../agents/crate-researcher.md |
| Rust version features | ../../agents/rust-changelog.md |
| Std library docs | ../../agents/std-docs-researcher.md |
| Third-party crate docs | ../../agents/docs-researcher.md |
| Clippy lints | ../../agents/clippy-researcher.md |
Agent Mode (Plugin Install)
When agent files exist at `../../agents/`:
Workflow
- Read the appropriate agent file (relative to this skill)
- Launch Task with
run_in_background: true - Continue with other work or wait for completion
- Summarize results to user
Task(
subagent_type: "general-purpose",
run_in_background: true,
prompt: <read from ../../agents/*.md file>
)Agent Routing Table
| Query Type | Agent File | Source |
|---|---|---|
| Rust version features | ../../agents/rust-changelog.md | releases.rs |
| Crate info/version | ../../agents/crate-researcher.md | lib.rs, crates.io |
| Std library docs (Send, Sync, Arc, etc.) | ../../agents/std-docs-researcher.md | doc.rust-lang.org |
| Third-party crate docs (tokio, serde, etc.) | ../../agents/docs-researcher.md | docs.rs |
| Clippy lints | ../../agents/clippy-researcher.md | rust-clippy docs |
Agent Mode Examples
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: <agent content>)
3. Wait for agent
4. Summarize resultsRust 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: <agent content>)
3. Wait for agent
4. Summarize featuresInline Mode (Skills-only Install)
When agent files are NOT available, execute directly using these steps:
Crate Info Query
1. actionbook: mcp__actionbook__search_actions("lib.rs crate info")
2. Get action details: mcp__actionbook__get_action_by_id(<action_id>)
3. agent-browser CLI (or WebFetch fallback):
- open "https://lib.rs/crates/{crate_name}"
- get text using selector from actionbook
- close
4. Parse and format outputOutput Format:
markdown
## {Crate Name}
**Version:** {latest}
**Description:** {description}
**Features:**
- `feature1`: description
**Links:**
- [docs.rs](https://docs.rs/{crate}) | [crates.io](https://crates.io/crates/{crate}) | [repo]({repo_url})Rust Version Query
1. actionbook: mcp__actionbook__search_actions("releases.rs rust changelog")
2. Get action details for selectors
3. agent-browser CLI (or WebFetch fallback):
- open "https://releases.rs/docs/1.{version}.0/"
- get text using selector from actionbook
- close
4. Parse and format outputOutput Format:
markdown
## Rust 1.{version}
**Release Date:** {date}
### Language Features
- Feature 1: description
- Feature 2: description
### Library Changes
- std::module: new API
### Stabilized APIs
- `api_name`: descriptionStd Library Docs (std::*, Send, Sync, Arc, etc.)
1. Construct URL: "https://doc.rust-lang.org/std/{path}/"
- Traits: std/{module}/trait.{Name}.html
- Structs: std/{module}/struct.{Name}.html
- Modules: std/{module}/index.html
2. agent-browser CLI (or WebFetch fallback):
- open <url>
- get text "main .docblock"
- close
3. Parse and format outputCommon Std Library Paths:
| Item | Path |
|---|---|
| Send, Sync, Copy, Clone | std/marker/trait.{Name}.html |
| Arc, Mutex, RwLock | std/sync/struct.{Name}.html |
| Rc, Weak | std/rc/struct.{Name}.html |
| RefCell, Cell | std/cell/struct.{Name}.html |
| Box | std/boxed/struct.Box.html |
| Vec | std/vec/struct.Vec.html |
| String | std/string/struct.String.html |
Output Format:
markdown
## std::{path}::{Name}
**Signature:**{signature}
**Description:**
{description}
**Examples:**{example_code}
Third-Party Crate Docs (tokio, serde, etc.)
1. Construct URL: "https://docs.rs/{crate}/latest/{crate}/{path}"
2. agent-browser CLI (or WebFetch fallback):
- open <url>
- get text ".docblock"
- close
3. Parse and format outputOutput Format:
markdown
## {crate}::{path}
**Signature:**{signature}
**Description:**
{description}
**Examples:**{example_code}
Clippy Lints
1. agent-browser CLI (or WebFetch fallback):
- open "https://rust-lang.github.io/rust-clippy/stable/"
- search for lint name in page
- get text ".lint-doc" for matching lint
- close
2. Parse and format outputOutput Format:
markdown
## Clippy Lint: {lint_name}
**Level:** {warn|deny|allow}
**Category:** {category}
**Description:**
{what_it_checks}
**Example (Bad):**{bad_code}
**Example (Good):**{good_code}
Tool Chain Priority
Both modes use the same tool chain order:
- actionbook MCP - Get pre-computed selectors first
mcp__actionbook__search_actions("site_name")→ get action IDmcp__actionbook__get_action_by_id(id)→ get URL + selectors
- agent-browser CLI - Primary execution tool
bash
agent-browser open <url>
agent-browser get text <selector_from_actionbook>
agent-browser close- 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
Deprecated Patterns
| Deprecated | Use Instead | Reason |
|---|---|---|
| WebSearch for crate info | Task + agent or inline mode | Structured data |
| Direct WebFetch | actionbook + agent-browser | Pre-computed selectors |
| Guessing version numbers | Always fetch from source | Prevents misinformation |
Error Handling
| Error | Cause | Solution |
|---|---|---|
| Agent file not found | Skills-only install | Use inline mode |
| 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. Use agents or inline mode instead.
