feat: add railway skills command for installing agent skills

[m-abdelwahab]

Summary

• Adds railway skills (alias: install, update. both run the same install flow; update reads more naturally when re-running to pick up upstream changes) which installs Railway agent skills into ~/.agents/skills and any detected AI-coding-tool directories (Claude Code, Cursor, Codex, OpenCode).
• Adds railway skills remove to cleanly uninstall.
• --agent <slug> targets a specific tool instead of auto-detection. Valid slugs: universal, claude-code, codex, opencode, cursor.
• Root-level railway --help surfaces a tip pointing users at the command.

Usage

Discovery — tip in railway --help:

Interact with Railway via CLI

Tip: Using an AI coding agent? Run `railway skills install` to enhance it with Railway expertise — deploying, debugging, managing services.

Usage: railway [COMMAND]
...

Default install — writes to ~/.agents/skills plus any detected tool dirs:

$ railway skills install

Railway Skills

Installing to: Universal (.agents), Claude Code, OpenAI Codex, Cursor

✓ Universal (.agents): installed use-railway → /Users/mahmoud/.agents/skills/use-railway
✓ Claude Code: installed use-railway → /Users/mahmoud/.claude/skills/use-railway
✓ OpenAI Codex: installed use-railway → /Users/mahmoud/.codex/skills/use-railway
✓ Cursor: installed use-railway → /Users/mahmoud/.cursor/skills/use-railway

Skills installed successfully!
! You may need to restart your tool(s) to load skills.

Re-running via the update alias picks up upstream changes:

$ railway skills update
# (same output as `railway skills install`)

Target a specific tool with --agent <slug>:

$ railway skills install --agent claude-code

Railway Skills

Installing to: Claude Code

✓ Claude Code: installed use-railway → /Users/mahmoud/.claude/skills/use-railway

Skills installed successfully!
! You may need to restart your tool(s) to load skills.

Unknown agent errors with the valid list:

$ railway skills install --agent bogus
Error: Unknown agent: 'bogus'

Valid agents: universal, claude-code, codex, opencode, cursor

Uninstall:

$ railway skills remove

Railway Skills

Removing from: Universal (.agents), Claude Code, OpenAI Codex, Cursor

✓ Universal (.agents): removed use-railway
✓ Claude Code: removed use-railway
✓ OpenAI Codex: removed use-railway
✓ Cursor: removed use-railway

Skills removed successfully.

Help — railway skills --help:

Install Railway agent skills for AI coding tools (Claude Code, Cursor, Codex, OpenCode, and all tools that support .agents/skills)

Always installs to ~/.agents/skills. Additionally installs to any detected tool directories (e.g. ~/.claude/skills, ~/.cursor/skills). Use --agent to target specific tools instead of auto-detection.

Usage: railway skills [OPTIONS] [COMMAND]

Commands:
  install  Install Railway agent skills for AI coding tools (Claude Code, Cursor, Codex, OpenCode, and all tools that support .agents/skills)
  remove   Remove Railway skills from all tools
  help     Print this message or the help of the given subcommand(s)

Options:
      --agent <AGENT>
          Target specific agent(s) instead of all detected (e.g. --agent claude-code)

  -h, --help
          Print help (see a summary with '-h')

  -V, --version
          Print version

Test plan

• cargo build and cargo clippy pass
• railway skills install installs to ~/.agents/skills plus any detected tool dirs
• railway skills update behaves identically to railway skills install
• railway skills install --agent claude-code installs only to Claude Code
• railway skills install --agent bogus errors with the valid-agents list
• railway skills remove cleans up all installed skills; re-running hits the "not installed, skipping" branch
• railway --help shows the tip right below "Interact with Railway via CLI"

🤖 Generated with Claude Code