Skills are replacing custom assistants
Since April the assistants have moved into Word and Docs, saved instructions have a new format, and the EU disclosure rule has started.
Four things to do about it
- Write your voice and your house rules once, as a skill, and keep a copy in a plain file outside any vendor.
- Try the writing tools inside Word and Docs before you buy a separate product.
- For work that reaches the EU, record who reviewed the text and who is responsible for it.
- Look at your client's Google Ads account for text that Google's AI wrote.
Three vendors moved saved instructions to "skills" in September
A skill is a saved set of instructions that the assistant loads when the task needs it.
| Date | Vendor | Change | Source |
|---|---|---|---|
| 11 September 2026 | OpenAI | Plans to retire custom GPTs and move users to plugins that "combine reusable instructions with connected apps" | ChatGPT release notes |
| 15 September 2026 | Notion | Shared team skills: "reusable instructions that teach AI how your team works" | Notion releases |
| 30 September 2026 | Gemini skills, which "will soon replace Gems" | Gemini release notes |
Google's example is about writing: "combining a writing style skill with a brand guidelines skill to create on-brand assets in your voice". Claude had skills and plugins before this period.
Agencies now sell the same idea to clients. R/GA launched a product on 16 September 2026 that turns a brand into "machine writable toolkits" for agents that write and design (R/GA). Vercel keeps its copy rules in a file inside a skill. One rule reads: "Destructive CTAs follow Verb + Noun." Vercel also reports that agents failed to use an available skill "in 56% of cases", so a person still reviews the work (Vercel, 25 June 2026).
If your agency keeps house-style or client GPTs, plan to move them. Keep the text portable, because the models change too. Anthropic made eight model launches between April and September, and it suspended access to two of its models for 19 days in June (Claude release notes).
The assistants work inside the document
- Google Docs added "Match writing style", which "helps maintain a consistent tone and style across your entire doc" (Google Workspace Updates, 22 April 2026).
- Microsoft Word has ChatGPT in a sidebar: "draft from notes, summarize a document, revise selected text, and adjust headings and formatting" (ChatGPT release notes, 17 September 2026).
- Microsoft 365 Copilot added Anthropic's Claude as a model you can select, and Sonnet 5 in Word on the web (Microsoft release notes, June and August 2026).
- Outlook coaches you on a draft email and lets you accept each suggestion on its own (same notes, August 2026).
Memory and instructions got larger
- Claude's memory became a list of separate entries on 10 July 2026. From 25 August you can read, edit and delete each one, and memory is off by default for Team and Enterprise organisations (Claude release notes).
- ChatGPT's paid plans raised the limit on custom instructions from 1,500 to 5,000 characters (ChatGPT release notes, 15 July 2026).
5,000 characters is enough for a voice profile with examples.
Disclosure rules have dates
| Date | Rule | What it means for text |
|---|---|---|
| 2026 | UK Advertising Association guide | Review scales with risk. Disclosure "should be proportionate to the potential for consumer harm or misinterpretation". Guide |
| 11 June 2026 | UK CAP advice | "The Code is media‑neutral, meaning the rules apply regardless of how the content was created." CAP |
| 2 August 2026 | EU AI Act, Article 50 | AI-generated text that informs the public on matters of public interest must be disclosed. The duty does not apply where the text "has undergone a process of human review or editorial control" and a person or company "holds editorial responsibility". Article 50 |
The US state laws that started in 2026 are about images, video, audio and AI-generated performers. California's AI Transparency Act says its requirements "do not apply to AI-generated textual content" (Morgan Lewis, 3 August 2026).
Google and LinkedIn moved against volume
- Google's guide for its AI search features says: "Don't just recycle what others on the internet have already said, or could easily be produced by a generative AI model." (Google Search Central, 15 May 2026)
- Google also says files such as llms.txt are not needed for Google Search and do not change rankings (documentation updates, 15 June 2026).
- LinkedIn said it is adding a "Seems like AI slop" report option and removing its "enhance your post" AI writing feature (Relevant Audience, citing TechCrunch, 3 August 2026).
- Google told advertisers that from 1 September 2026 it would move Search campaigns that used automatically created assets into AI Max, with AI text customisation on by default (PPC Land, 6 August 2026).
Ask the model to answer in plain technical English
On 2 October 2026 Andrej Karpathy posted on X:
"Ask your LLM to explain something in ASD-STE100, it's a controlled language specification originally developed for aerospace maintenance documentation."
He uses it for model output that he has to read. He sometimes asks for "80% of the way to ASD-STE100" because the full specification is strict, and he ranks diagrams and web pages above it. Search Engine Journal reported the post the same day.
Try it on your next long answer: "Explain this in ASD-STE100 Simplified Technical English."