# Supported Source Formats for Installing Skills in the Skills CLI > Discover the 10 supported source formats for installing skills via the skills CLI. Easily install from local paths, GitHub shorthand, URLs, and more. - Repository: [Vercel Labs/skills](https://github.com/vercel-labs/skills) - Tags: how-to-guide - Published: 2026-04-23 --- **The `skills` CLI supports ten distinct source formats for installing skills: local file paths, GitHub shorthand, full GitHub URLs, GitHub prefixed shorthand, GitLab URLs, GitLab prefixed shorthand, well-known HTTP endpoints, direct git URLs, source aliases, and fragment refs with skill filters.** The `skills add` command in the [vercel-labs/skills](https://github.com/vercel-labs/skills) repository accepts a wide variety of source specifications. All parsing logic is centralized in [`src/source-parser.ts`](https://github.com/vercel-labs/skills/blob/main/src/source-parser.ts), which converts each input string into a structured `ParsedSource` object. Understanding these supported source formats for installing skills helps you integrate both local and remote skill sources efficiently. ## Local File System Paths The parser identifies local paths through the `isLocalPath()` function at lines 10-20 in [`src/source-parser.ts`](https://github.com/vercel-labs/skills/blob/main/src/source-parser.ts). This check covers absolute paths, relative paths starting with `./` or `../`, and Windows drive letters. ```bash # Relative path skills add ./my-skill # Parent directory skills add ../shared-skills/authentication # Absolute path (Unix) skills add /home/user/skills/my-skill # Absolute path (Windows) skills add C:\Users\me\skills\my-skill ``` ## GitHub Shorthand The most compact remote format uses `owner/repo` syntax. The parser applies regex `^([^/]+)\/([^/]+)(?:\/(.+?))?\/?$` at lines 60-68 to match this pattern, with additional handling for `@skill-name` filters at lines 48-55. ```bash # Basic shorthand skills add vercel/nextjs-skill # With subpath to specific skill directory skills add vercel/nextjs-skill/path/to/skill # With skill filter (installs only matching skill) skills add vercel/nextjs-skill@mySkill ``` ## Full GitHub URLs For explicit control over branches and paths, the parser supports complete GitHub URLs through three distinct patterns in [`src/source-parser.ts`](https://github.com/vercel-labs/skills/blob/main/src/source-parser.ts): - `githubTreeWithPathMatch` (lines 64-74): `.../tree/branch/path` - `githubTreeMatch` (lines 76-85): `.../tree/branch` - `githubRepoMatch` (lines 87-96): Plain repository URL ```bash # Plain repository URL skills add https://github.com/vercel/nextjs-skill # Specific branch skills add https://github.com/vercel/nextjs-skill/tree/main # Branch with subpath skills add https://github.com/vercel/nextjs-skill/tree/main/agents/hello ``` ## GitHub Prefixed Shorthand The `github:` prefix provides an alternative to raw shorthand, handled by `githubPrefixMatch` at line 45 of [`src/source-parser.ts`](https://github.com/vercel-labs/skills/blob/main/src/source-parser.ts). The parser strips the prefix and reprocesses the remainder recursively. ```bash skills add github:vercel/nextjs-skill skills add github:vercel/nextjs-skill@mySkill ``` ## GitLab URLs and Shorthand GitLab support mirrors GitHub's structure with adaptations for GitLab's URL patterns. The parser implements: - `gitlabTreeWithPathMatch` (lines 99-115): `/-/tree/branch/path` - `gitlabTreeMatch` (lines 117-127): `/-/tree/branch` - `gitlabRepoMatch` (lines 129-144): Plain repository URL, including sub-groups The `gitlab:` prefix shorthand (lines 52-63) transforms to HTTPS URLs. ```bash # Full GitLab URL with subpath skills add https://gitlab.com/group/subgroup/repo/-/tree/main/agents/hello # GitLab prefixed shorthand skills add gitlab:group/subgroup/repo ``` ## Well-Known HTTP Endpoints Non-git HTTP sources are supported through `isWellKnownUrl()` at lines 92-115 in [`src/source-parser.ts`](https://github.com/vercel-labs/skills/blob/main/src/source-parser.ts). This filter excludes known git hosts and `.git` suffixes, allowing arbitrary HTTPS URLs that serve skill definitions. ```bash skills add https://example.com/.well-known/agent-skills/index.json ``` ## Direct Git URLs As a fallback, any URL resembling a raw git repository (SSH, HTTP, or other protocols) returns `{type: 'git', url: input}` at lines 182-188 of [`src/source-parser.ts`](https://github.com/vercel-labs/skills/blob/main/src/source-parser.ts). ```bash # SSH git URL skills add git@github.com:vercel/nextjs-skill.git # HTTP git URL skills add https://git.example.com/skills/authentication.git ``` ## Source Aliases and Fragment Refs The parser supports two additional convenience features: **Source aliases** defined in `SOURCE_ALIASES` (lines 27-30) rewrite inputs before parsing: ```bash skills add coinbase/agentWallet # Rewrites to canonical URL ``` **Fragment refs and skill filters** (`parseFragmentRef` and `appendFragmentRef`, lines 81-119) append to any source format: ```bash # Fragment ref (checks out specific tag/branch) skills add vercel/nextjs-skill#v1.2.3 # Combined fragment ref and skill filter skills add vercel/nextjs-skill#v1.2.3@mySkill ``` ## Summary - **Local paths**: Absolute, relative (`./`, `../`), and Windows drive formats - **GitHub shorthand**: `owner/repo` with optional subpaths and `@skill` filters - **GitHub URLs**: Full HTTPS URLs with branch and path specifications - **GitHub prefixed**: `github:owner/repo` alternative syntax - **GitLab support**: Mirror of GitHub with `/-/tree/` URL patterns and `gitlab:` prefix - **Well-known endpoints**: Arbitrary HTTPS URLs excluding git hosts - **Direct git URLs**: SSH and HTTP git protocol fallbacks - **Aliases and filters**: Source rewriting and fragment-based refinements ## Frequently Asked Questions ### How does the skills CLI distinguish between a local path and a GitHub shorthand? The `isLocalPath()` function in [`src/source-parser.ts`](https://github.com/vercel-labs/skills/blob/main/src/source-parser.ts) (lines 10-20) checks for `path.isAbsolute()`, `./` or `../` prefixes, and Windows drive letter patterns (`C:\` or `C:/`). If any match, the input is treated as a local file system path. Otherwise, the parser attempts GitHub shorthand and URL matching. ### Can I install a skill from a specific branch or tag? Yes. Append a fragment ref using `#` syntax to any source format. For example: `skills add vercel/nextjs-skill#v1.2.3` or `skills add https://github.com/vercel/nextjs-skill/tree/develop#main`. The `parseFragmentRef` function (lines 81-119 in [`src/source-parser.ts`](https://github.com/vercel-labs/skills/blob/main/src/source-parser.ts)) extracts these references for checkout during installation. ### Does the skills CLI support private GitHub repositories? Private repositories are supported through direct git URLs using SSH authentication: `skills add git@github.com:owner/private-repo.git`. The parser's fallback logic (lines 182-188) returns `{type: 'git', url: input}` for any URL pattern not matching other categories, allowing SSH and authenticated HTTPS protocols to pass through to the installation layer in [`src/install.ts`](https://github.com/vercel-labs/skills/blob/main/src/install.ts).