Jack Basics

This skill teaches you how to work effectively in Jack Cloud projects.

What This Skill Provides

• How to query and modify Jack databases (D1)
• How to deploy and check status
• How to use Jack MCP tools when available
• Common patterns and troubleshooting

Key Concept

Jack projects use cloud infrastructure. Databases run on Cloudflare's edge network, not locally. Use Jack tools for all operations.

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Database Operations

Query Data

jack db execute "SELECT * FROM users LIMIT 10"

Modify Data

jack db execute --write "INSERT INTO users (name, email) VALUES ('Alice', 'alice@example.com')"

View Schema

jack db execute "SELECT name FROM sqlite_master WHERE type='table'"
jack db execute "PRAGMA table_info(users)"

Create Table

jack db execute --write "CREATE TABLE posts (id INTEGER PRIMARY KEY, title TEXT, created_at TEXT DEFAULT CURRENT_TIMESTAMP)"

MCP Tools (Preferred When Available)

Check if mcp__jack__* tools are in your available tools:

Tool	Purpose
mcp__jack__execute_sql	Query or modify database
mcp__jack__list_databases	List project databases
mcp__jack__create_database	Create new D1 database

Example MCP usage:

mcp__jack__execute_sql
  sql: "SELECT * FROM users"
  allow_write: false

For writes, set allow_write: true.

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Deployment

Deploy to Production

jack ship

Check Deployment Status

jack info

Shows: live URL, last deploy time, attached services.

Stream Production Logs

jack logs

Local Development

jack dev

Runs locally with remote bindings (real D1, KV, R2).

MCP Tools

Tool	Purpose
mcp__jack__deploy_project	Deploy to production
mcp__jack__get_project_status	Check deployment status
mcp__jack__tail_logs	Stream production logs

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Services

List All Services

jack services

Create Services

jack services db create        # D1 database
jack services kv create        # KV namespace
jack services storage create   # R2 bucket
jack services vectorize create # Vector index

MCP Tools

Tool	Purpose
mcp__jack__create_database	Create D1 database
mcp__jack__create_storage_bucket	Create R2 bucket
mcp__jack__create_vectorize_index	Create vector index

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Secrets

Set a Secret

jack secrets set STRIPE_SECRET_KEY

Prompts for value (hidden input).

Set Multiple Secrets

jack secrets set API_KEY WEBHOOK_SECRET

List Secrets

jack secrets list

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Project Structure

Typical Jack project:

my-project/
├── src/
│   └── index.ts          # Worker entry point
├── wrangler.jsonc        # Cloudflare config (bindings, routes)
├── package.json
└── .jack/
    └── project.json      # Jack project link

• wrangler.jsonc - Defines D1 bindings, KV namespaces, environment
• .jack/project.json - Links to Jack Cloud (managed) or your Cloudflare account (BYO)

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Troubleshooting

"Database not found"

Create one:

jack services db create

"Not a Jack project"

Link the directory:

jack link --byo

MCP tools not available

Install MCP config:

jack mcp install

Then restart your AI assistant.

Need to see what went wrong

Stream production logs:

jack logs

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Quick Reference

Task	Command
Query database	jack db execute "SELECT ..."
Write to database	jack db execute --write "INSERT ..."
Deploy	jack ship
Check status	jack info
Stream logs	jack logs
Local dev	jack dev
Create database	jack services db create
Set secret	jack secrets set KEY

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Summary

1. Use jack commands for all operations
2. Use MCP tools when available (mcp__jack__*)
3. Databases are remote - D1 runs on Cloudflare's edge
4. Deploy with jack ship - handles build and deployment
5. Check logs with jack logs - debug production issues