Go I18n

Go CLI i18n

Overview

This skill documents the Go CLI i18n rules used in this repo, including language detection, locale files, and key naming conventions.

When to Use

• You add or edit any user-facing CLI string in cmd/skills-x
• You need to add a new skill description for list output
• You are troubleshooting mixed language output or missing translations

Architecture Snapshot

• i18n runtime: cmd/skills-x/i18n/i18n.go
• Locale files: cmd/skills-x/i18n/locales/zh.yaml, cmd/skills-x/i18n/locales/en.yaml
• Embed: //go:embed locales/*.yaml (locales are embedded at build time)

Language Selection

Priority order in detectLanguage():

1. SKILLS_LANG
2. LANG
3. LC_ALL
4. Default: zh

Normalization uses prefix matching:

• zh, zh_CN, zh_TW → zh
• en, en_US → en
• Unsupported → zh

Using i18n in Go

Initialize once (early in main):

import "github.com/castle-x/skills-x/cmd/skills-x/i18n"

i18n.MustInit()

Translate strings:

title := i18n.T("list_header")
msg := i18n.Tf("init_success", skillName)

Missing keys return the key itself (useful for spotting gaps).

Key Naming Conventions

Use lowercase + underscores with category prefixes:

• app_ app metadata
• cmd_ command descriptions/flags
• list_ list output
• init_ init output
• err_ error messages
• cat_ category names
• skill_ skill descriptions
• meta_ meta warnings

Rule: Never mix Chinese and English in the same string. Use two locale keys instead.

Adding New Strings

1. Add the same key to both locale files:

• cmd/skills-x/i18n/locales/zh.yaml
• cmd/skills-x/i18n/locales/en.yaml

1. Use i18n.T / i18n.Tf in Go code.
2. Rebuild (make build) to embed the updated YAML.
3. Test:

• SKILLS_LANG=zh ./bin/skills-x list
• SKILLS_LANG=en ./bin/skills-x list

New Skill Description

Add a skill_ key to both locale files. The list view reads descriptions from i18n, not from the skill file.

Example

# locales/en.yaml
init_success: "Installed: %s"

# locales/zh.yaml
init_success: "安装成功: %s"

fmt.Println(i18n.Tf("init_success", skillName))

Quick Reference

| Item | Value | |------|-------| | Locale files | cmd/skills-x/i18n/locales/{zh,en}.yaml | | Init | i18n.MustInit() | | Translate | i18n.T, i18n.Tf | | Language priority | SKILLS_LANG > LANG > LC_ALL > zh |

Common Mistakes

• Only adding a key in one locale file
• Hardcoding mixed-language strings
• Forgetting to rebuild after YAML changes
• Formatting with fmt.Sprintf before calling i18n.Tf

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: castle-x
• Source: castle-x/skills-x
• License: MIT

Install and usage instructions live in the source repository linked above.