Mcp MCP Server

Claude Code plugin for Val Town

Installs the Val Town MCP server and skills for Claude Code.

Contains platform guidance for building on Val Town — the single source of truth for the "how to write a val" knowledge used by Val Town's own tools (Townie, the MCP server) and by AI coding tools like Claude Code.

Each skill is a short markdown guide covering one platform topic (HTTP vals, cron/intervals, SQLite, email, OAuth, React UI, third-party integrations, templates).

Install

Claude Code

Start a claude session, then run:

/plugin marketplace add val-town/plugins

Then run:

/plugin install vals@valtown

OpenAI Codex

Add the marketplace, then install the plugin:

codex plugin marketplace add val-town/plugins
codex /plugins

Codex reads the native marketplace at .agents/plugins/marketplace.json (and falls back to the Claude .claude-plugin/marketplace.json for compatibility).

Cursor

Install from the Cursor Marketplace, or add this repo as a marketplace source. Cursor reads .cursor-plugin/marketplace.json and the per-plugin plugin/.cursor-plugin/plugin.json.

---

Either way, this makes the platform skills available to the agent and registers the hosted Val Town MCP server (https://api.val.town/v3/mcp). On first use of an MCP tool, the agent runs the OAuth flow in your browser.

Contributing

Authoring skills

Skills live in plugin/skills/<name>/SKILL.md with YAML frontmatter:

---
name: http-endpoints
description: Use when building an HTTP val — a web endpoint, API route, webhook...
triggers: [http, endpoint, webhook, api, request, response]
---

# HTTP Endpoints

...guide body...

• name (required) — must match the directory name; lowercase, hyphens, ≤64 chars.
• description (required) — written as "Use when…"; this is how Claude decides to load the skill. ≤1024 chars.
• triggers (optional) — keyword hints that boost searchSkills ranking; ignored by Claude Code's native loader.

Keep content audience-neutral: only platform knowledge true for every consumer. No product-flow or chat-only advice.

Then build:

npm install
npm run build   # generate src/generated/skills.ts, then tsc
npm test        # build + smoke tests

npm run generate validates every skill against both our schema and Claude Code's frontmatter constraints — a skill that wouldn't load in Claude Code fails the build.

Relationship to the Val Town monorepo

This package is the source of truth for skill content. The Val Town app and MCP server consume it as a dependency rather than holding their own copy. See docs/SKILLS_PLUGIN.md in the main repo for the full design.

Versioning

This repository uses Changesets for publishing. See their documentation for more information.

• For each change that should trigger a new version, you should run npx @changesets/cli and fill out the interactive prompts to describe the changes. This will generate a new changeset in the .changesets directory.
• Each change in that directory will prompt the release.yml GitHub action to create a new release PR.
• Merging a release PR will automatically publish a new version of this module.