Codex Lang Coach — Development skill for Claude Code

Language Coach

Language Coach is a local-first Codex plugin that turns everyday writing into focused, reusable language lessons. It reviews the language in a prompt, highlights meaningful corrections and patterns, and stores only structured learning notes in a private local database.

The project includes a Codex plugin, an MCP interface, a local Node.js runtime, and a browser-based learning dashboard.

Features

• Reviews grammar, spelling, collocations, word choice, tone, and contextual appropriateness.
• Produces natural target-language rewrites instead of literal translations.
• Captures reusable structures, phrases, and transfer examples.
• Tracks native-, target-, mixed-, and other-language usage.
• Provides progress summaries and correction-category trends.
• Includes a local dashboard for reviewing and deleting learning notes.
• Stores data locally in SQLite by default.
• Lets users opt into registration, verified-email login, and remote sync.
• Stores remote notes in Neon Postgres through Cloudflare Hyperdrive.
• Enforces account ownership in both the Worker API and Postgres row-level security policies.
• Deploys the authenticated dashboard as a Cloudflare Worker website.
• Avoids saving unrelated task context, files, or task answers.

Installation

Install in the Codex app

1. Open the Plugins tab.
2. Click the Add button in the top-right corner of the Plugins page.
3. In the Add plugin marketplace dialog, enter:
   • Source: git@github.com:jackeydou/codex-lang-coach.git
   • Git ref: marketplace
   • Sparse paths: leave empty
4. Click Add marketplace.
5. Find Language Coach in the added marketplace and install it.


Review and trust the plugin hooks after installation, then start a new Codex task so the plugin runtime