Explained Consulting
Custom GPTs are retiring. The skills you build carry forward. Leave knowing how to find a skill, try it safely and build your own.
Doug
Elijah
Today
Brian
Nash
Today's promise: you leave knowing how to find a plugin, try it safely and build your own.
explained.consulting
Custom GPTs stop working on every ChatGPT plan. When you migrate one, its instructions become a skill.
| Date | What happens |
|---|---|
| Sep 11, 2026 | OpenAI announces Custom GPTs will retire across ChatGPT plans |
| Oct 26, 2026 | Some Enterprise workspaces: no new Custom GPTs after this date |
| Dec 11, 2026 | Standard retirement: GPTs and their pages stop working |
| Feb 11, 2027 | Latest date, for Enterprise workspaces with an approved deferral |
Instead of pasting the same long prompt into every chat, you saved it once. No code required.
How it should behave, in plain English.
Files it can read: price sheets, policies, FAQs.
Calls out to other tools, set up by a developer.
Build it once. Share it with your team, or publish it in the GPT Store.
Connect plugins to let ChatGPT work across your tools
Simplified view of ChatGPT: GPTs, Plugins, then the Skills tab
Both use a SKILL.md file with a name, a description and instructions.
| ChatGPT | Claude | |
|---|---|---|
| Find plugins | Plugins in the sidebar (chatgpt.com/plugins) | Customize, then Plugins, then Discover |
| Who gets them | Directory open across plans; some plugins vary by plan | Paid plans: Pro, Max, Team, Enterprise |
| Build by chatting | @plugin-creator | Plugin Create |
| Other ways to make a skill | Codex Record & Replay | Upload a skill folder, or record your screen (Mac) |
| Share with your team | Workspace tab and admin controls | Share menu on Team and Enterprise |
If you've built a Custom GPT, you already know how to build a skill.
A plain text folder you own. Copy it, share it, upload it wherever you work.
| Piece | Think of it as | Example |
|---|---|---|
| Skill | A training manual | "Write a quote using our price sheet" |
| App (connector) | The keys to your tools | Gmail, Google Calendar, QuickBooks, HubSpot |
| Plugin | A toolbox | Content Studio: research + newsletter writer + web search |
| Agent | An employee with a job description | Your newsletter draft is ready Monday at 7am |
Written once. Used every time that job comes up.
A SKILL.md file with your steps, rules and format, plus reference files like a price sheet.
AI reads only the name and description, then opens the rest when your request matches.
The same file runs in Claude, ChatGPT and Codex. You own it.
The AI reads only the name and description until it decides the skill fits. Then it loads the rest.
"Helps with content."
"Use when I ask what's new, what's going on in my industry or market, or for research for a post or newsletter. Finds this month's news and why it matters."
AI reads only the name and description until it decides a skill fits. A vague one never runs.
Use the words you actually type: "what's new," "my industry," "my market."
And what it gives back: this month's news, and why it matters. Under 200 characters.
A skill that does too much gets confused. Two jobs? Build two skills.
The jobs you repeat are the ones worth writing down. Skip the moonshot.
One clear input, one clear result. You should know when it's done.
Prices, policies, VIPs. The things AI can't guess.
Same sections, same length, every time. Show an example.
Read-only first. A person approves anything that goes out.
--- name: industry-research description: Use when I ask what's new, what's going on in my industry or market, or for research for a post or newsletter. Finds this month's news and why it matters. --- ## Steps 1. Read config.md for my industry and my readers. 2. Search the web for news from the last 30 days in my industry. 3. Pick the 5 stories my readers would care about most. ## Rules - Every story needs a date and a working link. No link, drop it. - Last 30 days only. No rumors. Research only. ## Output For each story: headline, date, link, and one line on why it matters to my readers.
"Write this week's newsletter."
It guesses, or it asks: topic, audience, format? Every single week.
Two SKILL.md files, config.md and voice.md. The answers, written once.
Open a text file. Name, description, steps, rules, output.
From a library or a colleague. Read it, then Skills → Add.
"Help me build a skill that…" It interviews you and writes the file.
After a good session: "Can you turn what we just did into a skill?"
Both folders: Plugins → Skills → Add.
"What's new in my industry?" "Write this week's newsletter." "Reply to this customer."
Change one line to yours. Same skill, new news.
"Now make it a LinkedIn post."
If a test fails, fix the description first. It's almost always the culprit.
| Library | What's in it | Link |
|---|---|---|
| Anthropic Skills | Official. Word, Excel, PowerPoint, PDF, brand guidelines, skill-creator | github.com/anthropics/skills |
| Anthropic Knowledge Work Plugins | Productivity, Small Business, Sales, Marketing, Support, Finance | github.com/anthropics/knowledge-work-plugins |
| Marketing Skills | Copywriting, SEO audit, cold email, pricing, social, ads | github.com/coreyhaines31/marketingskills |
| OpenAI Skills Catalog | PDF, transcription, Notion meeting notes. Built for Codex | github.com/openai/skills |
| Awesome Claude Skills | Curated list: documents, writing, business and app skills | github.com/ComposioHQ/awesome-claude-skills |
| Awesome Agent Skills | 1,000+ skills. Works in Claude, ChatGPT/Codex and more | github.com/VoltAgent/awesome-agent-skills |
| skills.sh | Search every public skill, ranked by installs | skills.sh |
Download the folder, read the SKILL.md, then upload it under Skills in Claude or ChatGPT.
Your tone, phrases and banned words. Other skills use it
Drafts replies, summarizes long threads
Research into a newsletter and post. We'll build this one
Outline, draft and keyword check
Checks drafts against your own checklist
Sales coaching, interview practice, training
A sounding board for pricing and decisions
Transcript in, to-dos out
Your format, your price sheet
Answers from your policies and FAQ
The same breakdown every week
What matters today, from your inbox and calendar
Not "an assistant." One narrow job, with your own material inside.
Built by developers, often the software company itself. You install them. You don't build them.
Read your Gmail, calendar, QuickBooks or CRM.
Draft an email, create an invoice, book a job.
Many come with ready-made skills for that tool.
Install, connect your account, done.
Your skills say how. Plugins give them something to work with.
| Plugin or connector | Where | Try this prompt | Why it matters |
|---|---|---|---|
| Gmail or Outlook | Both | "Which customer emails need a reply today?" | Inbox triage in 30 seconds |
| Google Calendar | Both | "What does my week look like, and where am I double-booked?" | Week at a glance |
| Google Drive or Notion | Both | "Find our latest price sheet and summarize what changed." | Stop hunting for files |
| HubSpot | Both | "Which deals haven't been touched in 14 days?" | Pipeline that doesn't go stale |
| QuickBooks | Both | "Who owes us money past 30 days?" | Cash you can see |
| Canva | Both | "Turn this promo into 3 social posts sized for Instagram and Facebook." | Marketing without a designer |
| Claude for Small Business | Claude | "Chase my overdue invoices." | 15 ready workflows across finance, sales and operations |
| Zendesk | ChatGPT | "Summarize this week's top support issues." | Support trends without reading every ticket |
| Data plugin | ChatGPT | "Break down last quarter's sales by service line." | Analysis without wrestling a spreadsheet |
| Plugin Creator / Plugin Create | Both | "Help me build a plugin that..." | The on-ramp to building your own |
Ask for summaries before you let it send anything.
A human hits send until you trust it.
Each plugin lists what it reads and what it can do. Connect a work account, not your whole life.
"What's new in my industry?" Five stories from the last 30 days, each with a date, a link and why it matters to my readers.
"Write this week's newsletter." Turns the research into a newsletter or LinkedIn post in my voice. Runs research first if it needs to.
My industry, my readers, my newsletter name, my writing samples and the words I never use.
"Put it in my Gmail drafts." The newsletter lands in your inbox, ready to read and send. Web search does the research.
Rules: no link, no story. Never invent facts or quotes. Draft only: it never sends or posts.
"Write this week's newsletter." It has to ask you four questions.
Name, description, steps, rules, output.
The answers to those four questions.
Skills in ChatGPT or Claude.
Research only, both skills, neither.
Change one line to the room's industry and rerun.
"Now make it a LinkedIn post."
Scheduled tasks: pick the time and how often, then type "Write this week's newsletter and put it in my Gmail drafts."
Ask in a chat: "Every Monday at 7am, write this week's newsletter and put it in my Gmail drafts." Confirm the card. It lives under Scheduled in the sidebar.
Schedule only what you've tested. It drafts. You still hit send.
That takes a voice agent, not a plugin.
Field service and practice management tools with no connector.
The ones that didn't survive the GPT migration.
Reliability, and fixing it when it breaks.
Getting everyone using it the same way.
Next up: Part 4, agents that work with your customers. Part 5, teams of agents.
Never miss another call. Never pay overtime.
Your paperwork is done before you get to the office.
Every lead followed up. Every review collected.
Every customer checked on. Nobody forgotten.
Every tech. Every job. Scheduled in real time.
Know your numbers without hiring a numbers person.
We'll find the skill or agent that saves you the most time.
Today's research and newsletter skills, a morning-brief skill and the "10 to try" sheet. Email me and I'll send it.
One boring, weekly job.
Your rules, your numbers, your format.
Test it, then put it on a schedule.
Naveen Aggarwal · naveen@explained.consulting · explained.consulting
