# Agent skills

If you write Hibiki code with a coding agent such as Claude Code, Codex or
Cursor, install the Hibiki skills first. Hibiki is a young library, and an
agent has seen little of it in training. Asked to write Hibiki code without
help, it fills the gaps with guesses, and it walks into the mistakes this
site warns about.

A skill is a folder of instructions written for an agent. Its main file,
`SKILL.md`, opens with a description of the tasks the skill is for. The
agent keeps that description in view and loads the rest only when a task
matches: first the body of `SKILL.md`, a short summary, and then the files
under `references/`, one at a time, as it needs the detail. A skill the
agent never uses costs it only the description.

The format is the open [Agent Skills](https://agentskills.io) standard,
which Claude Code, Codex, Gemini CLI, Cursor, GitHub Copilot, OpenCode and
many other agents read.

## The six skills

Hibiki is three gems, and the skills follow them. `hibiki` is the signals
library itself, plain Ruby with no opinion about the web; the
[introduction](/hibiki/introduction/) shows it in a dozen
lines. `hibiki_rails` uses signals to keep the interactive parts of a Rails
page up to date: the state lives on the server, and the server re-renders
the HTML and sends it to the browser whenever the state changes. The
[Rails introduction](/hibiki/rails-introduction/) explains
how. `hibiki_phlex` re-renders a [Phlex](https://www.phlex.fun) component
whenever a signal it read changes.

The core gem has one skill and so does Phlex. The Rails gem is large enough
to need four.

| Skill | Gem | What it covers |
| ----- | --- | -------------- |
| `hibiki` | `hibiki` | The three primitives, `state`, `derived` and `effect`; batching several writes; deciding when two values count as equal; signals as class attributes; threads. |
| `hibiki-rails` | `hibiki_rails` | Channels and islands, the two halves of a live part of a page; the JavaScript client; broadcasting to several browsers; loading state; ActiveRecord; troubleshooting. |
| `hibiki-rails-forms` | `hibiki_rails` | Live forms with `ReactiveForm`, including nested forms, multi-select associations and file uploads. |
| `hibiki-rails-scaffold` | `hibiki_rails` | Every `hibiki:rails:*` generator, among them a CRUD scaffold as general as `rails g scaffold`, with its options and the notices it prints. |
| `hibiki-rails-motion` | `hibiki_rails` | Enter and leave transitions for elements the server adds or removes: `data-motion` and the `hbk-*` CSS utilities. |
| `hibiki-phlex` | `hibiki_phlex` | Reactive Phlex components with `Hibiki::Phlex.render_effect`. |

Each skill condenses pages of this site, and every file under `references/`
ends with a link to the page it condenses, so an agent that wants the full
account can find it. The source is the
[`skills/`](https://github.com/planetaska/hibiki/tree/main/skills) directory
of the core repository.

## Installing the skills

The [`skills` CLI](https://github.com/vercel-labs/skills), a third-party
installer from Vercel, reads that directory straight from GitHub. Name the
agent you use with `-a`. To install all six skills for Claude Code in the
current project:

```sh
npx skills add planetaska/hibiki --skill '*' -a claude-code
```

The agent ids you are most likely to want are `claude-code`, `codex`,
`gemini-cli`, `cursor`, `github-copilot`, `opencode`, `windsurf` and `zed`.
Pass `-a` more than once to install for several agents.

To list the six without installing anything:

```sh
npx skills add planetaska/hibiki --list
```

To install one skill in the agent's global folder rather than the project:

```sh
npx skills add planetaska/hibiki --skill hibiki-rails-forms -a claude-code --global
```

### What the CLI writes

Everything in this section is the `skills` CLI's own behavior, the same for
any skill it installs. Hibiki's skills neither ask for nor change any of it.

The CLI keeps one copy of each skill in `.agents/skills/`, the folder that
Codex, Cursor, Copilot and many other agents share. Agents with their own
folder get a link or a copy there as well: Claude Code reads
`.claude/skills/`, which holds links back to `.agents/skills/`.

It also writes `skills-lock.json` in the project root. The file records
where each skill came from and a hash of its contents, much as a
`package-lock.json` records packages. Commit it if you want your team to
install the same skills.

The first time you run the CLI interactively, it asks:

> Install the find-skills skill? It helps your agent discover and suggest skills.

`find-skills` is a skill published by the CLI's authors. With it installed,
your agent searches the public skills directory at
[skills.sh](https://skills.sh) and suggests `npx skills add` commands for
skills it finds. The Hibiki skills work the same whichever way you answer,
and the CLI asks only once.

### The `--all` flag

The CLI's `--all` flag installs every skill for every agent it supports and
answers each prompt yes:

```sh
npx skills add planetaska/hibiki --all
```

Besides `.agents/skills/` and `.claude/skills/`, it creates `agent/skills/`
for Eve, another agent the CLI supports, whether or not you use Eve. Use
`--all` only when you want the skills in front of every agent.

You can also install by hand. Copy a skill's directory from the repository
into your agent's skills folder: `.claude/skills/` for Claude Code,
`.agents/skills/` for Codex, Cursor and Copilot, or the global folder your
agent documents.

## How an agent chooses a skill

Once the skills are installed you have nothing more to do. The agent matches
each task against the six descriptions and loads the skill that fits. Ask
why a derived value never recomputes, and it loads `hibiki`. Ask for a live
edit form, and it loads `hibiki-rails-forms`. Ask it to run a scaffold
command, and it loads `hibiki-rails-scaffold`.

When a task spans two areas, the `hibiki` skill directs the agent. It holds
a table that maps what the agent is looking at, a channel file or a
generator command, to the skill that covers it.

You can also load a skill yourself by name. In Claude Code, type
`/hibiki-rails`.

## Updating after a release

A skill describes particular versions of the gems, and the `metadata` block
at the top of its `SKILL.md` names them. The `hibiki` skill also lists the
versions of the three gems that are tested together. When you upgrade a gem,
run the same `npx skills add` command again to replace your copies.

The skills in the repository cannot fall behind the gems. The repository's
default `rake` task fails unless every skill names the current gem
versions, as recorded in the newest row of
[Version lockstep](/hibiki/version-lockstep/), and every
link in every skill resolves.

Agent skills

If you write Hibiki code with a coding agent such as Claude Code, Codex or Cursor, install the Hibiki skills first. Hibiki is a young library, and an agent has seen little of it in training. Asked to write Hibiki code without help, it fills the gaps with guesses, and it walks into the mistakes this site warns about.

A skill is a folder of instructions written for an agent. Its main file, SKILL.md, opens with a description of the tasks the skill is for. The agent keeps that description in view and loads the rest only when a task matches: first the body of SKILL.md, a short summary, and then the files under references/, one at a time, as it needs the detail. A skill the agent never uses costs it only the description.

The format is the open Agent Skills standard, which Claude Code, Codex, Gemini CLI, Cursor, GitHub Copilot, OpenCode and many other agents read.

The six skills

Hibiki is three gems, and the skills follow them. hibiki is the signals library itself, plain Ruby with no opinion about the web; the introduction shows it in a dozen lines. hibiki_rails uses signals to keep the interactive parts of a Rails page up to date: the state lives on the server, and the server re-renders the HTML and sends it to the browser whenever the state changes. The Rails introduction explains how. hibiki_phlex re-renders a Phlex component whenever a signal it read changes.

The core gem has one skill and so does Phlex. The Rails gem is large enough to need four.

Skill	Gem	What it covers
`hibiki`	`hibiki`	The three primitives, `state`, `derived` and `effect`; batching several writes; deciding when two values count as equal; signals as class attributes; threads.
`hibiki-rails`	`hibiki_rails`	Channels and islands, the two halves of a live part of a page; the JavaScript client; broadcasting to several browsers; loading state; ActiveRecord; troubleshooting.
`hibiki-rails-forms`	`hibiki_rails`	Live forms with `ReactiveForm`, including nested forms, multi-select associations and file uploads.
`hibiki-rails-scaffold`	`hibiki_rails`	Every `hibiki:rails:*` generator, among them a CRUD scaffold as general as `rails g scaffold`, with its options and the notices it prints.
`hibiki-rails-motion`	`hibiki_rails`	Enter and leave transitions for elements the server adds or removes: `data-motion` and the `hbk-*` CSS utilities.
`hibiki-phlex`	`hibiki_phlex`	Reactive Phlex components with `Hibiki::Phlex.render_effect`.

Each skill condenses pages of this site, and every file under references/ ends with a link to the page it condenses, so an agent that wants the full account can find it. The source is the skills/ directory of the core repository.

Installing the skills

The skills CLI, a third-party installer from Vercel, reads that directory straight from GitHub. Name the agent you use with -a. To install all six skills for Claude Code in the current project:

npx skills add planetaska/hibiki --skill '*' -a claude-code

The agent ids you are most likely to want are claude-code, codex, gemini-cli, cursor, github-copilot, opencode, windsurf and zed. Pass -a more than once to install for several agents.

To list the six without installing anything:

npx skills add planetaska/hibiki --list

To install one skill in the agent’s global folder rather than the project:

npx skills add planetaska/hibiki --skill hibiki-rails-forms -a claude-code --global

What the CLI writes

Everything in this section is the skills CLI’s own behavior, the same for any skill it installs. Hibiki’s skills neither ask for nor change any of it.

The CLI keeps one copy of each skill in .agents/skills/, the folder that Codex, Cursor, Copilot and many other agents share. Agents with their own folder get a link or a copy there as well: Claude Code reads .claude/skills/, which holds links back to .agents/skills/.

It also writes skills-lock.json in the project root. The file records where each skill came from and a hash of its contents, much as a package-lock.json records packages. Commit it if you want your team to install the same skills.

The first time you run the CLI interactively, it asks:

Install the find-skills skill? It helps your agent discover and suggest skills.

find-skills is a skill published by the CLI’s authors. With it installed, your agent searches the public skills directory at skills.sh and suggests npx skills add commands for skills it finds. The Hibiki skills work the same whichever way you answer, and the CLI asks only once.

The `--all` flag

The CLI’s --all flag installs every skill for every agent it supports and answers each prompt yes:

npx skills add planetaska/hibiki --all

Besides .agents/skills/ and .claude/skills/, it creates agent/skills/ for Eve, another agent the CLI supports, whether or not you use Eve. Use --all only when you want the skills in front of every agent.

You can also install by hand. Copy a skill’s directory from the repository into your agent’s skills folder: .claude/skills/ for Claude Code, .agents/skills/ for Codex, Cursor and Copilot, or the global folder your agent documents.

How an agent chooses a skill

Once the skills are installed you have nothing more to do. The agent matches each task against the six descriptions and loads the skill that fits. Ask why a derived value never recomputes, and it loads hibiki. Ask for a live edit form, and it loads hibiki-rails-forms. Ask it to run a scaffold command, and it loads hibiki-rails-scaffold.

When a task spans two areas, the hibiki skill directs the agent. It holds a table that maps what the agent is looking at, a channel file or a generator command, to the skill that covers it.

You can also load a skill yourself by name. In Claude Code, type /hibiki-rails.

Updating after a release

A skill describes particular versions of the gems, and the metadata block at the top of its SKILL.md names them. The hibiki skill also lists the versions of the three gems that are tested together. When you upgrade a gem, run the same npx skills add command again to replace your copies.

The skills in the repository cannot fall behind the gems. The repository’s default rake task fails unless every skill names the current gem versions, as recorded in the newest row of Version lockstep, and every link in every skill resolves.