opencode-data-model

OpenCode plugin for generating normalized, high-performance schemas and compile-safe TypeScript or JavaScript data models.

Why

I asked LLMs to generate schemas a million times. Too often they looked right, then failed on relationships, constraints, nullability, indexes, SQL dialects, or TypeScript boundaries. This plugin adds a stronger prompt contract, forced validation, and optional AI double-checking to reduce those mistakes before the model reaches your codebase.

Install

OpenCode loads plugins from two sources.

From npm (recommended)

Add the package to the plugin array in your config file. OpenCode installs npm plugins automatically with Bun at startup and caches them (and their dependencies) under ~/.cache/opencode/node_modules/.

{
  "$schema": "https://opencode.ai/config.json",
  "plugin": ["opencode-data-model"]
}

Both regular and scoped npm packages are supported. The same package works under npm or Bun — bun add opencode-data-model resolves the identical artifact.

From local files

Drop the built JavaScript/TypeScript file into a plugin directory and OpenCode loads it automatically at startup:

• .opencode/plugins/ — project-level plugins
• ~/.config/opencode/plugins/ — global plugins

mise run build
mise run link   # symlinks dist/index.js into ~/.config/opencode/plugins/

To use external packages from a local plugin, create a package.json inside your config directory, or publish to npm and reference it from config instead.

Load order

Plugins load from all sources, and every hook runs in sequence:

1. Global config (~/.config/opencode/opencode.json)
2. Project config (opencode.json)
3. Global plugin directory (~/.config/opencode/plugins/)
4. Project plugin directory (.opencode/plugins/)

Duplicate npm packages with the same name and version load once. A local plugin and an npm plugin with similar names load separately.

Objects

Object	Command	Tool
Blueprint	/model	model_doc
MySQL Forge	/schema-mysql	schema_mysql
Postgres Forge	/schema-pg	schema_pg
Type Loom	/types-ts	types_ts
JSDoc Loom	/types-js	types_js
Quality Map	/data-model-roadmap	roadmap_model
Gatekeeper	/model-check	audit_model

Classic /data-model-* commands and generate_* tool names are still available for compatibility.

Prompt Contract

• Act as a principal data architect.
• Normalize write models first; document read-model exceptions.
• Design for correctness, query performance, maintainability, and migrations.
• Add indexes for real access patterns without over-indexing.
• Make nullability, ownership, deletion behavior, and constraints explicit.
• Keep TypeScript and JavaScript models compile-safe and boundary-aware.
• Reject the draft if validation finds hallucinated fields, missing relations, weak indexes, dialect errors, or type/interface drift.

Development

mise trust
bun install
mise run build
mise run lint
mise run test
mise run typecheck

Validation uses Bun snapshots, Zod contract checks, SQL DDL parsing, and TypeScript syntax checks. Update snapshots with mise run test_update.

Publishing

npm login
mise run publish --tag latest
# if your npm account enforces publish 2FA:
mise run publish --tag latest --otp <one-time-code>

License

MIT License. See LICENSE.