The AI handbook for builders

AI tools, terms, and skills, all in one place.

Compare two AI tools. Look up an acronym. Find a prompt that fits the job. Browse skills, workflows, and practical guides for people using AI at work.

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227 skills·56 compares·83 terms·223 prompts

Three ways to start

Install a skill

Hand-written Claude Skills you download once and Claude uses forever.

Browse 227 skills

Pick a tool

Honest head-to-heads on the AI tools you're evaluating right now.

Browse 56 compares

Look up a term

Tokens, RAG, MCP, agents — every AI term in plain English.

Browse 83 terms

This week

All spotlights

Skill of the Week

Ship an AI Feature on Claude — the gap between a demo and production

A Claude-powered feature is easy to demo and hard to ship. The demo works once on a happy-path input. Production brings weird inputs, costs that creep, hallucinations users see, and no way to tell when quality drifts. This bundle closes that gap.

Prompt of the Week

7 new prompts — research, newsletter, launch, investor emails

Structured paper summaries, cross-study comparison, newsletter issue builder, landing page copy, and two investor update templates.

Tool Drop

Claude Sonnet 5 — close to Opus, at Sonnet price

Anthropic shipped Sonnet 5 on June 30. It lands close to Opus 4.8 on agentic and knowledge-work evaluations at $2/$10 per million tokens through August. The one number to watch is the new tokenizer, which counts up to 1.35x more tokens, so measure real spend before you size a budget.

Sponsored

Deals of the Week — hand-picked from AppSumo

TidyCal$29 · lifetime
Booking and scheduling with built-in payment collection: Stripe, PayPal, package sales, subscriptions, and coupon codes all on one page. Connects to Google, Microsoft 365, and Apple calendars; handles group bookings and round-robin team routing on the Agency plan.
Reoon Email Verifier$79 · lifetime
Bulk-checks an email list for invalid, disposable, and unsafe addresses before you send, without ever contacting the address itself. Daily verification credits renew for as long as the license lasts, on top of a lifetime credit pool.
SheetXAI$49 · lifetime
An add-on for Google Sheets and Excel that takes a plain-English instruction and runs it across the sheet: cleaning up messy data, pulling fields out of attached documents, generating a column of text. Jobs finish in the background and email you when they are done, and it reaches out to HubSpot, WordPress, Google Analytics, and several hundred other apps.