GPT-5.5 is your new default. Here is what changed.
GPT-5.5 Instant is now your default ChatGPT model, memory sources are editable, and ChatGPT has landed inside Excel and Google Sheets. These three launches alone reshape how you work with AI.
What matters today
GPT-5.5 Instant is now your default ChatGPT model, memory sources are editable, and ChatGPT has landed inside Excel and Google Sheets. These three launches alone reshape how you work with AI.
Welcome byte
This issue gives executives a clean scan of GPT-5.5 is your new default. Here is what changed.. Start with the quick hits, then use the companion guides for the workflows worth testing this week.
Quick Hits
OpenAI GPT-5.5 Instant defaults for all users
GPT-5.3 Instant is out. GPT-5.5 is in -- as of May 5, for every ChatGPT user on every tier. Better accuracy, shorter responses, sharper STEM handling. No settings change required on your end. Read more
ChatGPT sidebar lands in Excel and Google Sheets
Build trackers, formulas, multi-tab scenarios, and data cleaning rules in plain English -- without leaving your spreadsheet. Available now via the Microsoft and Google Workspace marketplaces. Read more
Mastering Context Windows: The Secret to Long-Form AI Writing
Most users fail at long-form content generation because they treat the AI like a search engine rather than a collaborative writer. Read more
ChatGPT Is Now Inside Excel and Google Sheets
What the new ChatGPT sidebar does inside Excel and Google Sheets -- and what it cannot do Read more
Build a Live Weekly Revenue Tracker in Google Sheets -- No Formulas Required
The exact conversation sequence to build a complete weekly revenue tracker inside Google Sheets Read more
Top AI Updates
1. Mastering Context Windows: The Art of Long-Form Prompting
Modern LLMs now support context windows of 128k tokens or more. However, simply dumping a massive PDF into a prompt rarely yields the results you expect.
2. Mastering Context Windows: The Secret to Long-Form AI Writing
Most users fail at long-form content generation because they treat the AI like a search engine rather than a collaborative writer. When you ask for a 2,000-word article in one go, you are fighting against the model's token limit and its tendency to lose focus.
3. ChatGPT Is Now Inside Excel and Google Sheets
What the new ChatGPT sidebar does inside Excel and Google Sheets -- and what it cannot do
Pro Tip
As AI models expand their context windows to millions of tokens, the challenge has shifted from "how much can I fit" to "how do I keep the model from getting distracted.
Action items:
- Copy the prompt or framework into ChatGPT, Claude, or Gemini.
- Test Mastering Context Windows: The Art of Long-Form Prompting on one live decision, document, or meeting artifact.
- Save the best version as a reusable team template.
Copy-ready guide Mastering Context Windows: The Art of Long-Form Prompting
Productivity Gem
The exact conversation sequence to build a complete weekly revenue tracker inside Google Sheets
Action items:
- Choose one recurring workflow with a clear before and after.
- Run the Mastering Context Windows: The Art of Long-Form Prompting workflow once with real work, not sample data.
- Keep it only if it saves at least 30 minutes this week.
Put it to work Mastering Context Windows: The Art of Long-Form Prompting
Health Tip
As LLM context windows expand to 128k, 200k, and even 1M tokens, the challenge has shifted. It is no longer about fitting data into the window; it is about ensuring the model actually pays attention to the right parts of that data.
This information is for educational purposes only and is not medical advice. Please consult a qualified healthcare professional before making changes to your health routine.
Step-by-step guide Mastering Context Windows: The Art of Long-Form Prompting
Kids Tip
Kids create a hands-on AI project: Write Mom's Story With AI This Mother's Day. A parent or educator helps them build, test, and explain what the AI tool gets right and wrong.
Try the activity Write Mom's Story With AI This Mother's Day
Wrap Up
Pick one workflow from this issue, run it with real work, and keep the result only if it makes the next decision clearer or faster.
About the author
Pierre has spent 25+ years building growth systems across fintech, real estate, lending, campaigns, and AI workflows, with $1.5B+ in client value delivered.
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