What does it actually fix?

Drift and imprecision. Reproducing a whole draft to change one sentence meant good parts quietly changed while you were fixing a bad one, and describing which part you meant was unreliable. Holding the draft in place and letting you select within it removes both, which is why revision suddenly feels normal.

When should I stay in ordinary conversation?

While you are still deciding what the thing is. Exploring directions, weighing approaches or asking for three different openings all work better as an exchange, and moving to a single draft is the right step once you know roughly what you are making rather than before.

That depends on the product rather than on the arrangement, and it is worth checking rather than assuming. Some keep the artefact with the conversation, some let you export it, and some lose it when the session goes, which is an unpleasant thing to discover at the end of a long afternoon.

Glossary

Canvas

A canvas is a side panel holding the draft itself, and it matters because the unit of work stops being a message and becomes a document you revise.

In plain terms

A panel beside the conversation that holds the thing you are actually making. Instead of the whole draft being reproduced every time you ask for a change, it sits there and gets edited in place. You can select a paragraph and say what is wrong with that paragraph, which is how people have always worked on documents.

Why it matters

Because the older arrangement made revision quietly awful. Every small correction reproduced the entire piece, so good sentences drifted while you were fixing a bad one, and there was no way to point at anything. Moving the draft out of the conversation removes both problems and changes what the tool is useful for.

How it works

The draft lives outside the conversation and persists across turns, which is the whole mechanism. Changes are applied to it rather than producing a fresh copy, so the parts you did not mention stay exactly as they were, and that alone accounts for most of the improvement people notice.

You can point at things, and pointing turns out to be most of editing. Selecting a paragraph and saying what is wrong with it is precise in a way that describing its position never is, and it removes an entire class of frustration where the wrong section gets rewritten because the instruction was ambiguous.

Edits become visible as edits rather than as a new version. Seeing what changed lets you reject one thing without discarding the rest, and it makes an unrequested change noticeable, which in the older arrangement it frequently was not.

The trade is that the conversation becomes about the document, which is usually right and not always. Open-ended thinking, comparing several directions or generating alternatives is better served by ordinary conversation, and forcing that into a single evolving draft narrows the work prematurely.

Fixing one paragraph

It is worth noticing how much of the early frustration with these tools came from this one arrangement rather than from the quality of the writing. A draft that is regenerated in full each time cannot be revised, only replaced, and replacement is a terrible fit for work that is nearly right. People adapted by taking the output into a proper editor at the first sign of promise and finishing by hand, which was sensible and meant the assistance stopped exactly where it might have become most useful. Moving the artefact out of the exchange did not make anything smarter. It made the last mile possible, which is where most documents are actually made, and it is a good example of an interface decision doing more for usefulness than a capability improvement would have.

Seen in the wild

A builder that generates a project and holds a running preview beside the conversation, updating it as you keep talking rather than starting over.
Bolt
An assistant whose artefact panel holds a document or a piece of code beside the conversation, editable across turns.
Claude
A tool generating structured decks and documents that are then restyled and restructured directly rather than re-prompted from scratch.
Gamma

Common misconceptions

People assume

It is a display improvement.

In fact

It changes the unit of work from a message to a document, and everything follows from that. Persistent drafts, selective edits and visible changes are not presentation choices; they are what makes revision possible at all, which the older arrangement genuinely did not support.

People assume

It is better for everything.

In fact

It is better for revising one thing and worse for exploring several. Comparing directions, thinking out loud or generating alternatives all suit ordinary conversation, and committing to a single evolving draft too early narrows the work before you have decided what it should be.

Telling them apart

Canvas vs Conversation history

Canvas

The artefact, held outside the exchange.

Conversation history

The exchange itself, kept across sessions.

One preserves what you are making and the other preserves how you got there, and losing either one is a different kind of annoyance.

Questions

What does it actually fix?: Drift and imprecision. Reproducing a whole draft to change one sentence meant good parts quietly changed while you were fixing a bad one, and describing which part you meant was unreliable. Holding the draft in place and letting you select within it removes both, which is why revision suddenly feels normal.
When should I stay in ordinary conversation?: While you are still deciding what the thing is. Exploring directions, weighing approaches or asking for three different openings all work better as an exchange, and moving to a single draft is the right step once you know roughly what you are making rather than before.
Is my work saved?: That depends on the product rather than on the arrangement, and it is worth checking rather than assuming. Some keep the artefact with the conversation, some let you export it, and some lose it when the session goes, which is an unpleasant thing to discover at the end of a long afternoon.