# Golang Spf13 Cobra

Golang CLI command tree library using spf13/cobra, cobra.Command, RunE vs Run...

- Repository: https://github.com/samber/cc-skills-golang (3750 stars)
- Category: Testing
- License: MIT
- Last updated: 2026-11-01
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add samber/cc-skills-golang --skill golang-spf13-cobra -g -a claude-code -y`
Codex: `npx skills add samber/cc-skills-golang --skill golang-spf13-cobra -g -a codex -y`
Cursor: `npx skills add samber/cc-skills-golang --skill golang-spf13-cobra -g -a cursor -y`
Gemini CLI: `npx skills add samber/cc-skills-golang --skill golang-spf13-cobra -g -a gemini-cli -y`

## Description

Golang CLI command tree library using spf13/cobra, cobra.Command, RunE vs Run, PersistentPreRunE hook chain, Args validators (NoArgs, ExactArgs, MatchAll, custom), persistent vs local flags, command groups, ValidArgsFunction, RegisterFlagCompletionFunc, ShellCompDirective, usage/help template customization, man-page and markdown doc generation, and testing with SetArgs/SetOut/SetErr. Apply when using or adopting spf13/cobra, or when the codebase imports `github.com/spf13/cobra`. For configuration layering alongside cobra, see the `samber/cc-skills-golang@golang-spf13-viper` skill. For general CLI architecture (project layout, exit codes, signal handling, I/O patterns), see `samber/cc-skills-golang@golang-cli`.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

**Persona:** You are a Go CLI engineer building command trees that feel native to the Unix shell. You design the user-facing surface first, then wire behavior into the right hook.

**Modes:**

- **Build**, creating a new CLI from scratch: follow command tree setup, hook wiring, and flag sections sequentially.
- **Extend**, adding subcommands, flags, or completions to an existing CLI: read the current command tree first, then apply changes consistent with the existing structure.
- **Review**, auditing an existing CLI: check the Common Mistakes table, verify `RunE` usage, `OutOrStdout()`, hook chain ordering, and args validation.

# Using spf13/cobra for CLI command trees in Go

Cobra is the de facto standard for Go CLI applications. It provides the command/subcommand tree, flag parsing (via `pflag`), args validation, shell completion generation, and documentation generation. It does **not** handle configuration layering, that's viper's job.

**Official Resources:**

- [pkg.go.dev/github.com/spf13/cobra](https://pkg.go.dev/github.com/spf13/cobra)
- [github.com/spf13/cobra](https://github.com/spf13/cobra)
- [cobra.dev](https://cobra.dev)

This skill is not exhaustive, refer to library documentation and code examples for more information:

- For Go package docs, symbols, versions, importers, and known vulnerabilities, → See `samber/cc-skills-golang@golang-pkg-go-dev` skill (`godig`), preferred over Context7 for Go package facts.
- To navigate this library's usage in your own code (definitions, call sites, diagnostics), → See `samber/cc-skills-golang@golang-gopls` skill (`gopls`).
- Context7 remains a fallback for docs not indexed on pkg.go.dev.

```bash
go get github.com/spf13/cobra@latest
```

## Cobra vs. viper

These libraries do fundamentally different things and can be used independently.

The rest: https://github.com/samber/cc-skills-golang/blob/HEAD/skills/golang-spf13-cobra/SKILL.md