golang-pkg-go-dev

# golang-pkg-go-dev

**Dependencies:** `godig` — `go install github.com/samber/godig/cmd/godig@latest` (or use a registered godig MCP server / the hosted instance instead).

`godig` queries the [pkg.go.dev](https://pkg.go.dev) API. Use it to answer questions about Go packages and modules: docs, symbols, versions, importers and vulnerabilities. It works as a CLI and as an MCP server. All operations are **read-only** and need no authentication.

## When to use this skill

Trigger on questions like:

- "What versions of github.com/samber/lo are available?"
- "Does golang.org/x/text have known vulnerabilities?"
- "Show me the docs / symbols for package X."
- "Which packages import X?"
- "Search Go packages for Y."

## Choosing between `godig`, gopls, Context7, and govulncheck

In short: `godig` answers questions about the **published ecosystem** (works even for packages not yet in your `go.mod`); `gopls` reasons about **your locally resolved build** (`go.sum`, including `replace`d forks); Context7 is a fallback for non-Go or unindexed docs; `govulncheck` is the whole-tree vulnerability audit (→ `samber/cc-skills-golang@golang-security`). See the `samber/cc-skills-golang@golang-gopls` skill for wiring `gopls` (MCP server, native `LSP` tool, and CLI) with Claude Code, and the `samber/cc-skills-golang@golang-how-to` skill's "`godig` vs gopls vs Context7 vs govulncheck" section for the full task-to-tool matrix.

## Setup

### Install

```bash
go install github.com/samber/godig/cmd/godig@latest
```

### Register the MCP server (optional)

`godig mcp` runs over **stdio** by default, or **streamable HTTP** with `--transport http`. The command is harness-agnostic — any MCP-capable host can point at it. Claude Code registers it via its own CLI:

stdio (the client launches godig on demand):

```bash
claude mcp add pkg-go-dev -- godig mcp
```

streamable HTTP (shared server at `/mcp`, default `:8080`):

```bash
godig mcp --transport http --addr :8080
claude mcp add --transport http pkg-go-dev http://localhost:8080/mcp
```

Hosted instance (no install needed) — a public server runs at `https://godig.samber.dev/mcp`:

```bash
claude mcp add --transport http pkg-go-dev https://godig.samber.dev/mcp
```

Other MCP-capable harnesses (Cursor, Windsurf, and others) each have their own MCP server registration — an entry in their respective settings file pointing at the same `godig mcp` command or hosted URL, not a shared config format.

The CLI and the MCP server expose the **same** operations under matching names. Prefer the CLI when `godig` is installed; the hosted instance is a fallback when it is not.

## Commands

**Global flags (all commands):** `-o/--output table|json|raw|md` (default `table` — pass `-o md` for chat), `--base-url` (pkg.go.dev API), `--vuln-base-url` (Go vulnerability database, consulted by `vulns` and `overview`), `--timeout`, `--log-level debug|info|warn|error|off`. All are also settable via `GODIG_*` env vars.

| Command | Args | Specific flags | Purpose |
| --- | --- | --- | --- |
| `overview` | `<path>` | `--version` | Compact summary (metadata, versions, licenses, vulns) — start here |
| `search` | `<query>` | `--symbol --limit --filter` | Find packages (optionally exporting a symbol) |
| `package info` | `<path>` | `--module --version` | Package metadata |
| `package imports` | `<path>` | `--module --version` | Packages this package imports (plain list) |
| `package doc` | `<path>` | `--module --version --goos --goarch --format md\|text\|html\|markdown` | Full package doc (LARGE) |
| `package examples` | `<path>` | `--module --version --goos --goarch --symbol` | Runnable examples (LARGE; scope with `--symbol`) |
| `package licenses` | `<path>` | `--module --version` | License files, full text (LARGE) |
| `symbol doc` | `<path> <symbol>` | `--module --version --goos --goarch` | One symbol's signature + doc (token-efficient) |
| `symbol examples` | `<path> <symbol>` | `--module --version --goos --goarch` | One symbol's runnable examples |
| `symbols` | `<path>` | `--module --version --goos --goarch --limit --filter` | List exported symbols |
| `module info` | `<path>` | `--version` | Module metadata |
| `module licenses` | `<path>` | `--version` | Module license files (LARGE) |
| `module readme` | `<path>` | `--version` | Module README, full Markdown (LARGE) |
| `dependencies` | `<path>` | `--version` | go.mod deps: requires / replaces / excludes / go directive |
| `packages` | `<path>` | `--version --limit --filter` | Packages contained in a module |
| `versions` | `<path>` | `--limit --filter` | All versions, newest first |
| `major-versions` | `<path>` | `--limit --filter --exclude-pseudo` | Major versions (v1, v2 …) living as separate modules |
| `imported-by` | `<path>` | `--module --version --limit --filter` | Packages that import this one |
| `vulns` | `<path>` | `--version --limit` | Known vulnerabilities (from the Go vuln DB) |
| `mcp` | — | `--transport stdio\|http --addr --cache-ttl --cache-size` | Run as an MCP server |
| `version` | — | — | Print godig version / commit / build date |

When `godig` runs as an MCP server, each data command above is exposed as an operation of the same name.

**Exit codes:** `0` success, `1` runtime error (network, package not found), `2` usage error — a missing/invalid argument or flag (e.g. a non-positive `--limit`), or a command group invoked with no subcommand (`godig package`). Check for `2` to tell a malformed call apart from a failed lookup.

Full `-o md` output for every command: [sample-output.md](references/sample-output.md).

### Tips

- **Start with `overview`** — one call returns a compact summary (metadata, latest + recent versions, license types, vulnerabilities). Reach for `doc`/`examples`/`module readme`/`licenses` (LARGE) only when the full text is needed.
- **Always pass `-o md`** so results render as Markdown (tables, or raw doc/README) in the chat. Other formats exist (`table` default, `json`, `raw`) but prefer `md` her