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What AI tools are good at, and where they slip
Hand your AI tool the jobs it does well, and keep the ones it can't do well.
Recall
Recall (Lesson 1): Why can a fluent reply contain a date you never gave it?
Show the answerCheck your Lesson 1 answer, so the idea is fresh for this lesson.
It writes the likeliest words, and a likely date isn't a checked one.
The idea
These tools run on a language model, a program that writes text by predicting likely words.
They're strong at producing and reshaping text you give them: drafting, rewriting, summarising, explaining, brainstorming, and a first pass at code. They slip when the job needs a true fact that isn't in what you gave them.
Six jobs they do well, and why
Drafting from your notes
OpenAI lists "Drafting, rewriting, or summarizing content" among ChatGPT's main uses. Google lists "first drafts of outlines, emails, blog posts…". A draft fits because you supply the facts and the tool supplies the wording. Check for any fact you didn't give it.
Rewriting for a new reader
Shorter, plainer or more formal: the facts stay the same, and only the shape changes. That plays to the language model's strength, which is wording. Check that no fact was dropped or added on the way.
Summarising a long text
Google lists "a quick, easy to understand summary of more complex topics." A summary saves reading time, but it chooses what to leave out. It can also add a point that sounds right. Compare the key points with the original.
Explaining an idea in plain words
OpenAI lists "Answering questions and explaining concepts." This works well for a first grasp of a common idea. On niche or recent topics, details can be wrong. Check the details that matter before you rely on them.
Brainstorming options
OpenAI lists "Providing creative suggestions," and Google lists "Brainstorm ideas, develop a plan". A weak idea costs little here, because you choose which ones to keep.
A first pass at code
One of Google's own example prompts is "Debug this error message". A suggested fix is a good starting point. It isn't a passed test until you run it.
Where they slip
Google is direct about it: "Gemini Apps can make mistakes. When using Gemini Apps, double-check responses and don't rely on responses from Gemini Apps for professional advice." It also warns that Gemini "may give inaccurate or inappropriate information, including about people."
The pattern is the one from Lesson 1. When a job needs a fact you didn't supply, the tool predicts one. So treat a figure for a report as work to keep, or to check line by line. The same goes for a judgement about a person. Lesson 6 covers the kinds of AI tool and what each one can see.
EXAMPLE · the note and the budget are inventedSee how pasting your own note stops the tool inventing a budget.
Before
You type, "Summarise our meeting for the team." You give it no notes. The reply says "the team agreed a €20k budget". Nobody mentioned a budget.
After
You paste your three-line note and ask: "Rewrite this note in three short sentences for a teammate who missed the meeting. Use only the note. If it doesn't say, write 'not in the note'." The reply stays inside your three facts, and "budget: not in the note" appears.
Practice
Good fit or not?
| Job | Good fit? | What to check |
|---|---|---|
| Draft from your notes | Yes | Facts you didn't give it (Lesson 1) |
| Rewrite for a new reader | Yes | Dropped or added facts |
| Summarise a long text | Yes | Points left out or added |
| Explain an idea in plain words | Yes, with care | Details that matter (Lesson 4) |
| Brainstorm options | Yes | You choose |
| First pass at a code error | Yes | Run it |
| Supply a figure you'll publish | No, unless checked | Keep it (Lesson 8) |
| Make a decision about a person | No | Keep it (Lesson 8) |
Try it in your own AI tool (3 min)
Take a short note you're allowed to share. Ask for a three-sentence rewrite. Tell the tool to use only the note, and to write "not in the note" for anything missing. Then mark any sentence the note doesn't support.
Show the model answerCompare your marked sentences with ours, including one unsupported claim fixed.
"Two sentences matched my note. The third said 'the client approved', but my note said 'client to review'. I fixed that sentence before sending."
Check
SourcesOpen the 3 source pages behind this lesson's claims, all checked 2026-10-19.
- Google, Gemini Apps Help: "Use Gemini Apps"
- Google, Gemini Apps Help: "What you can do with your Gemini mobile app"
- OpenAI Help Center: "ChatGPT capabilities overview"