Rust Learner

What it does

When your agent uses it

• Asking about Rust versions
• Tasks that involve Technical documentation
• Tasks that involve Changelog and release notes

Example prompts

• “/rust-learner”

Requirements

• Pre-approved tools (allowed-tools): Task, Read, Glob, mcp__actionbook__*, Bash

Workflow steps

4 steps, taken from the first numbered list in SKILL.md.

1. 1Read the appropriate agent file (relative to this skill)
2. 2Launch Task with run_in_background: true
3. 3Continue with other work or wait for completion
4. 4Summarize results to user

What it can do on your machine

Read from SKILL.md and the folder at commit 75c1286. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves these tools, so the agent can use them without asking each time:

  • Task
  • Read
  • Glob
  • mcp__actionbook__*
  • Bash

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  No scripts in the folder and no shell commands in SKILL.md (its code samples are markdown and rust).

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  Hosts in commands or code, which the agent is likely to contact:

  • docs.rs
  • lib.rs
  • crates.io
  • releases.rs
  • doc.rust-lang.org

  Also links to:

  • rust-lang.github.io

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Rust Learner loads about 2k tokens when it runs. Until then it costs about 100 tokens; SKILL.md has 464 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~100

When it runs · the whole SKILL.md, loaded when a task matches

~2k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

• NotePre-approves every shell command (allowed-tools: Bash)SKILL.md

  allowed-tools: Task, Read, Glob, mcp__actionbook__*, Bash

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from fjrevoredo/mini-diarium at commit 75c1286, republished under its MIT licence (© fjrevoredo). 464 words, ~1,983 tokens.

name

rust-learner

description

Use when asking about Rust versions or crate info. Keywords: latest version, what's new, changelog, Rust 1.x, Rust release, stable, nightly, crate info, crates.io, lib.rs, docs.rs, API documentation, crate features, dependencies, which crate, what version, Rust edition, edition 2021, edition 2024, cargo add, cargo update, 最新版本, 版本号, 稳定版, 最新, 哪个版本, crate 信息, 文档, 依赖, Rust 版本, 新特性, 有什么特性

allowed-tools

Task, Read, Glob, mcp__actionbook__*, Bash

Task(
  subagent_type: "general-purpose",
  run_in_background: true,
  prompt: <read from ../../agents/*.md file>
)

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 results

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 features

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 output

## {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})

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 output

## Rust 1.{version}

**Release Date:** {date}

### Language Features
- Feature 1: description
- Feature 2: description

### Library Changes
- std::module: new API

### Stabilized APIs
- `api_name`: description

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 output

## std::{path}::{Name}

**Signature:**
```rust
{signature}

{example_code}

### Third-Party Crate Docs (tokio, serde, etc.)

**Output Format:**
```markdown
## {crate}::{path}

**Signature:**
```rust
{signature}

{example_code}

### Clippy Lints

**Output Format:**
```markdown
## Clippy Lint: {lint_name}

**Level:** {warn|deny|allow}
**Category:** {category}

**Description:**
{what_it_checks}

**Example (Bad):**
```rust
{bad_code}

{good_code}

---

## Tool Chain Priority

Both modes use the same tool chain order:

1. **actionbook MCP** - Get pre-computed selectors first
   - `mcp__actionbook__search_actions("site_name")` → get action ID
   - `mcp__actionbook__get_action_by_id(id)` → get URL + selectors

2. **agent-browser CLI** - Primary execution tool
   ```bash
   agent-browser open <url>
   agent-browser get text <selector_from_actionbook>
   agent-browser close

actionbook → agent-browser → WebFetch (only if agent-browser unavailable)

© fjrevoredo, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

Just SKILL.md in .agents/skills/rust-learner of fjrevoredo/mini-diarium.

Open the folder on GitHubat commit 75c1286

Used in 1 other repository

We found 1 copy of this SKILL.md (exact, near-identical or edited) in other folders, from 1 other GitHub owner. This page covers the copy in fjrevoredo/mini-diarium, which our catalogue first saw on October 7, 2026.

• NeverSight/learn-skills.devdata/skills-md/actionbook/rust-skills/rust-learner