---
summary: "Skills: managed vs workspace, gating rules, and config/env wiring"
read_when:
  - Adding or modifying skills
  - Changing skill gating or load rules
title: "Skills"
---

# Skills (SKYKOI)

SKYKOI uses **[KoiSkills](https://koiskills.io)-compatible** skill folders to teach the koi how to use tools. Each skill is a directory containing a `SKILL.md` with YAML frontmatter and instructions. SKYKOI loads **bundled skills** plus optional local overrides, and filters them at load time based on environment, config, and binary presence.

## Locations and precedence

Skills are loaded from **three** places:

1. **Bundled skills**: shipped with the install (npm package or SKYKOI.app)
2. **Managed/local skills**: `~/.SKYKOI/skills`
3. **Workspace skills**: `<workspace>/skills`

If a skill name conflicts, precedence is:

`<workspace>/skills` (highest) → `~/.SKYKOI/skills` → bundled skills (lowest)

Additionally, you can configure extra skill folders (lowest precedence) via
`skills.load.extraDirs` in `~/.SKYKOI/SKYKOI.json`.

## Per-koi vs shared skills

In **multi-koi** setups, each koi has its own workspace. That means:

- **Per-koi skills** live in `<workspace>/skills` for that koi only.
- **Shared skills** live in `~/.SKYKOI/skills` (managed/local) and are visible
  to **all kois** on the same machine.
- **Shared folders** can also be added via `skills.load.extraDirs` (lowest
  precedence) if you want a common skills pack used by multiple kois.

If the same skill name exists in more than one place, the usual precedence
applies: workspace wins, then managed/local, then bundled.

## Plugins + skills

Plugins can ship their own skills by listing `skills` directories in
`SKYKOI.plugin.json` (paths relative to the plugin root). Plugin skills load
when the plugin is enabled and participate in the normal skill precedence rules.
You can gate them via `metadata.SKYKOI.requires.config` on the plugin’s config
entry. See [Plugins](/tools/plugin) for discovery/config and [Tools](/tools) for the
tool surface those skills teach.

## SKYKOI Skills (install + sync)

SKYKOI Skills is the public skills registry for SKYKOI. Browse at
[https://SKYKOI.com/skills](https://SKYKOI.com/skills). Use it to discover, install, update, and back up skills.
Full guide: [SKYKOI Skills](/tools/SKYKOI Skills).

Common flows:

- Install a skill into your workspace:
  - `SKYKOI Skills install <skill-slug>`
- Update all installed skills:
  - `SKYKOI Skills update --all`
- Sync (scan + publish updates):
  - `SKYKOI Skills sync --all`

By default, `SKYKOI Skills` installs into `./skills` under your current working
directory (or falls back to the configured SKYKOI workspace). SKYKOI picks
that up as `<workspace>/skills` on the next session.

## Security notes

- Treat third-party skills as **untrusted code**. Read them before enabling.
- Prefer sandboxed runs for untrusted inputs and risky tools. See [Sandboxing](/gateway/sandboxing).
- `skills.entries.*.env` and `skills.entries.*.apiKey` inject secrets into the **host** process
  for that koi turn (not the sandbox). Keep secrets out of prompts and logs.
- For a broader threat model and checklists, see [Security](/gateway/security).

## Format (KoiSkills + Pi-compatible)

`SKILL.md` must include at least:

```markdown
---
name: nano-banana-pro
description: Generate or edit images via Gemini 3 Pro Image
---
```

Notes:

- We follow the KoiSkills spec for layout/intent.
- The parser used by the embedded koi supports **single-line** frontmatter keys only.
- `metadata` should be a **single-line JSON object**.
- Use `{baseDir}` in instructions to reference the skill folder path.
- Optional frontmatter keys:
  - `homepage` — URL surfaced as “Website” in the macOS Skills UI (also supported via `metadata.SKYKOI.homepage`).
  - `user-invocable` — `true|false` (default: `true`). When `true`, the skill is exposed as a user slash command.
  - `disable-model-invocation` — `true|false` (default: `false`). When `true`, the skill is excluded from the model prompt (still available via user invocation).
  - `command-dispatch` — `tool` (optional). When set to `tool`, the slash command bypasses the model and dispatches directly to a tool.
  - `command-tool` — tool name to invoke when `command-dispatch: tool` is set.
  - `command-arg-mode` — `raw` (default). For tool dispatch, forwards the raw args string to the tool (no core parsing).

    The tool is invoked with params:
    `{ command: "<raw args>", commandName: "<slash command>", skillName: "<skill name>" }`.

## Gating (load-time filters)

SKYKOI **filters skills at load time** using `metadata` (single-line JSON):

```markdown
---
name: nano-banana-pro
description: Generate or edit images via Gemini 3 Pro Image
metadata:
  {
    "SKYKOI":
      {
        "requires": { "bins": ["uv"], "env": ["GEMINI_API_KEY"], "config": ["browser.enabled"] },
        "primaryEnv": "GEMINI_API_KEY",
      },
  }
---
```

Fields under `metadata.SKYKOI`:

- `always: true` — always include the skill (skip other gates).
- `emoji` — optional emoji used by the macOS Skills UI.
- `homepage` — optional URL shown as “Website” in the macOS Skills UI.
- `os` — optional list of platforms (`darwin`, `linux`, `win32`). If set, the skill is only eligible on those OSes.
- `requires.bins` — list; each must exist on `PATH`.
- `requires.anyBins` — list; at least one must exist on `PATH`.
- `requires.env` — list; env var must exist **or** be provided in config.
- `requires.config` — list of `SKYKOI.json` paths that must be truthy.
- `primaryEnv` — env var name associated with `skills.entries.<name>.apiKey`.
- `install` — optional array of installer specs used by the macOS Skills UI (brew/node/go/uv/download).

Note on sandboxing:

- `requires.bins` is checked on the **host** at skill load time.
- If an koi is sandboxed, the binary must also exist **inside the container**.
  Install it via `kois.defaults.sandbox.docker.setupCommand` (or a custom image).
  `setupCommand` runs once after the container is created.
  Package installs also require network egress, a writable root FS, and a root user in the sandbox.
  Example: the `summarize` skill (`skills/summarize/SKILL.md`) needs the `summarize` CLI
  in the sandbox container to run there.

Installer example:

```markdown
---
name: gemini
description: Use Gemini CLI for coding assistance and Google search lookups.
metadata:
  {
    "SKYKOI":
      {
        "emoji": "♊️",
        "requires": { "bins": ["gemini"] },
        "install":
          [
            {
              "id": "brew",
              "kind": "brew",
              "formula": "gemini-cli",
              "bins": ["gemini"],
              "label": "Install Gemini CLI (brew)",
            },
          ],
      },
  }
---
```

Notes:

- If multiple installers are listed, the gateway picks a **single** preferred option (brew when available, otherwise node).
- If all installers are `download`, SKYKOI lists each entry so you can see the available artifacts.
- Installer specs can include `os: ["darwin"|"linux"|"win32"]` to filter options by platform.
- Node installs honor `skills.install.nodeManager` in `SKYKOI.json` (default: npm; options: npm/pnpm/yarn/bun).
  This only affects **skill installs**; the Gateway runtime should still be Node
  (Bun is not recommended for WhatsApp/Telegram).
- Go installs: if `go` is missing and `brew` is available, the gateway installs Go via Homebrew first and sets `GOBIN` to Homebrew’s `bin` when possible.
- Download installs: `url` (required), `archive` (`tar.gz` | `tar.bz2` | `zip`), `extract` (default: auto when archive detected), `stripComponents`, `targetDir` (default: `~/.SKYKOI/tools/<skillKey>`).

If no `metadata.SKYKOI` is present, the skill is always eligible (unless
disabled in config or blocked by `skills.allowBundled` for bundled skills).

## Config overrides (`~/.SKYKOI/SKYKOI.json`)

Bundled/managed skills can be toggled and supplied with env values:

```json5
{
  skills: {
    entries: {
      "nano-banana-pro": {
        enabled: true,
        apiKey: "GEMINI_KEY_HERE",
        env: {
          GEMINI_API_KEY: "GEMINI_KEY_HERE",
        },
        config: {
          endpoint: "https://example.invalid",
          model: "nano-pro",
        },
      },
      peekaboo: { enabled: true },
      sag: { enabled: false },
    },
  },
}
```

Note: if the skill name contains hyphens, quote the key (JSON5 allows quoted keys).

Config keys match the **skill name** by default. If a skill defines
`metadata.SKYKOI.skillKey`, use that key under `skills.entries`.

Rules:

- `enabled: false` disables the skill even if it’s bundled/installed.
- `env`: injected **only if** the variable isn’t already set in the process.
- `apiKey`: convenience for skills that declare `metadata.SKYKOI.primaryEnv`.
- `config`: optional bag for custom per-skill fields; custom keys must live here.
- `allowBundled`: optional allowlist for **bundled** skills only. If set, only
  bundled skills in the list are eligible (managed/workspace skills unaffected).

## Environment injection (per koi run)

When an koi run starts, SKYKOI:

1. Reads skill metadata.
2. Applies any `skills.entries.<key>.env` or `skills.entries.<key>.apiKey` to
   `process.env`.
3. Builds the system prompt with **eligible** skills.
4. Restores the original environment after the run ends.

This is **scoped to the koi run**, not a global shell environment.

## Session snapshot (performance)

SKYKOI snapshots the eligible skills **when a session starts** and reuses that list for subsequent turns in the same session. Changes to skills or config take effect on the next new session.

Skills can also refresh mid-session when the skills watcher is enabled or when a new eligible remote node appears (see below). Think of this as a **hot reload**: the refreshed list is picked up on the next koi turn.

## Remote macOS nodes (Linux gateway)

If the Gateway is running on Linux but a **macOS node** is connected **with `system.run` allowed** (Exec approvals security not set to `deny`), SKYKOI can treat macOS-only skills as eligible when the required binaries are present on that node. The koi should execute those skills via the `nodes` tool (typically `nodes.run`).

This relies on the node reporting its command support and on a bin probe via `system.run`. If the macOS node goes offline later, the skills remain visible; invocations may fail until the node reconnects.

## Skills watcher (auto-refresh)

By default, SKYKOI watches skill folders and bumps the skills snapshot when `SKILL.md` files change. Configure this under `skills.load`:

```json5
{
  skills: {
    load: {
      watch: true,
      watchDebounceMs: 250,
    },
  },
}
```

## Token impact (skills list)

When skills are eligible, SKYKOI injects a compact XML list of available skills into the system prompt (via `formatSkillsForPrompt` in `pi-coding-agent`). The cost is deterministic:

- **Base overhead (only when ≥1 skill):** 195 characters.
- **Per skill:** 97 characters + the length of the XML-escaped `<name>`, `<description>`, and `<location>` values.

Formula (characters):

```
total = 195 + Σ (97 + len(name_escaped) + len(description_escaped) + len(location_escaped))
```

Notes:

- XML escaping expands `& < > " '` into entities (`&amp;`, `&lt;`, etc.), increasing length.
- Token counts vary by model tokenizer. A rough OpenAI-style estimate is ~4 chars/token, so **97 chars ≈ 24 tokens** per skill plus your actual field lengths.

## Managed skills lifecycle

SKYKOI ships a baseline set of skills as **bundled skills** as part of the
install (npm package or SKYKOI.app). `~/.SKYKOI/skills` exists for local
overrides (for example, pinning/patching a skill without changing the bundled
copy). Workspace skills are user-owned and override both on name conflicts.

## Config reference

See [Skills config](/tools/skills-config) for the full configuration schema.

## Looking for more skills?

Browse [https://SKYKOI.com/skills](https://SKYKOI.com/skills).

---
