Shopify Sidekick and your theme: what it can change, and what still needs a developer.

What Sidekick is

Sidekick is the AI assistant built into the Shopify admin, on desktop and in the Shopify app (Shopify). It’s included with your plan, with features and usage limits that vary by plan (Shopify), and it works in 20 languages (Shopify, Summer ’25 Edition). Since December 2025 you can describe a change to your theme and Sidekick makes it, or pick a section or block in the preview and ask for a change to that one (Shopify, 2025).

What it can change in your theme

Sidekick changes a theme only from the theme editor or Canvas (Shopify). There it can:

• Change the theme’s settings: fonts, colors, buttons, spacing, whatever the theme offers. “Make the buttons rounded” is one request if the theme has a setting for it.
• Change a section’s or block’s settings, on the one you pick in the preview.
• Add, move, hide and remove sections and blocks, as long as the theme already includes them.
• Write text for a text field (Shopify).
• Generate a new block from a short description, in a section built to accept generated blocks (Shopify). Shopify advises reviewing what it writes before you publish.

It can work on an unpublished theme, and nothing it changes takes effect until you save.

What it can’t change

• Your checkout and customer accounts. In that editor it answers questions and links to settings, but it can’t change them (Shopify).
• A section your theme doesn’t have. It adds only what the theme includes. A generated block goes only where a section accepts one.
• Anything with no setting. A different header layout, a new product page arrangement, a spacing rule the theme fixes in its code: Shopify doesn’t say Sidekick edits a theme’s code, so a change like that is still a developer’s job.

Your theme decides how much Sidekick can do

Sidekick works from your theme’s settings, so the theme sets its limits. If the theme has a setting for button corners, rounding them is a request to Sidekick. If it doesn’t, it’s a ticket, a quote and a wait. Two themes that look alike can leave very different amounts to Sidekick.

To see how much yours leaves, open the theme editor and look through Theme settings, then a section or two. Whatever you can change there, Sidekick can change for you. Whatever you can’t, it can’t either.

Canvas, and the files Sidekick reads first

Canvas is Shopify’s newer tool for making or changing a theme with Sidekick: every template side by side, with Sidekick and the settings beside them. It’s in early access, on desktop only (Shopify). A theme made in Canvas carries two files: AGENTS.md, which says how the theme is built, and DESIGN.md, which records the store’s design direction. Sidekick reads both before it makes a change (Shopify), and any theme can carry them (Shopify).

How our theme works with Sidekick

Every look in a theme on our core is a setting, never a value written into the code: over 200 of them, grouped by what they change. So the button shape, the spacing, the colors and the fonts are each a request to Sidekick. The theme also comes with its own AGENTS.md and DESIGN.md, so Sidekick, and any AI tool your team uses, starts from the theme’s rules and your brand (the technical spec).

Our sections take the blocks built for them rather than generated ones, so each one stays what your design says. A new kind of section or block is built into the theme, in the same code as the rest.

Related: New Shopify theme, Theme features, Our theme’s files for AI tools.