Develop

Implement Subframe designs in the codebase. Fetch the design via MCP, sync components, and add business logic.

Connect to Subframe MCP before implementing

Before installing dependencies, syncing components, or editing code for a linked design, discover the Subframe get_page_info tool (use tool search if your client loads MCP tools on demand). The Subframe Docs MCP server only provides documentation; it cannot fetch the user's designs.

If get_page_info is unavailable, tell the user that you cannot access the linked design yet and help them connect the Subframe MCP server:

• Not installed/configured: Direct them to the Subframe MCP setup guide for their client. The design server URL is https://mcp.subframe.com/mcp.
• Already configured: Ask them to enable/connect the server and complete OAuth authentication in their client's MCP settings.
• Status unknown: Explain that the server may need installation, enabling, or authentication. Provide the setup guide and ask them to check their client's MCP settings.

Pause the design-dependent work until the tools are available. Do not silently fall back to opening or scraping the design in a browser, guessing from the prompt, or implementing from existing code alone. This also applies when using the design as inspiration in a non-Subframe project; connecting MCP does not require installing Subframe components into that project.

After the user reports that setup is complete, discover the tool again and successfully fetch the requested design with get_page_info before implementing it.

Only switch to a workflow without the linked design if the user explicitly chooses that alternative.

Detect Project State

Before starting, check for package.json and .subframe/ folder in the current directory:

Existing non-Subframe project

If the current directory has a package.json but no .subframe/ folder, ask the user which approach they prefer:

• Use the design as inspiration — Fetch the design via MCP for reference, but implement the page using the existing styles, components, and patterns already in the repo. Translate the Subframe design's layout and structure into whatever UI framework the project already uses (e.g., existing component library, CSS modules, styled-components). Do NOT install Subframe or sync components. Skip to Inspiration Workflow.
• Use Subframe styles and components — Install Subframe into the project so the design renders pixel-perfect with Subframe's generated code. Run /subframe:install first, then continue with the Workflow below.

Workflow

1. Wait for any in-flight design jobs — see Awaiting In-Flight Designs
2. Fetch the design — get_page_info with the URL, ID, or name
3. Read design documentation — get_project_info and get_component_info return any attached design docs; check them for usage guidance, accessibility notes, or constraints before implementing
4. Sync any missing components — Only if components don't exist locally. npx @subframe/cli sync for the specific components used in the page
5. Create the page — put it in the right place per codebase patterns
6. Add business logic — data fetching, forms, events, loading/error states

Awaiting In-Flight Designs

If a design was just kicked off in the same conversation (via /subframe:design), the underlying AI job is likely still running. Reading the result via get_*_info too early returns empty or stale code.

design_page, design_component, and edit_component return a jobId. Before the first read, call:

wait_for_jobs({ jobIds: [jobId1, jobId2, ...] })

Each result is running, done (with a summary — for design_page it reports how many requested pages were actually applied), error (the job failed or stopped reporting; don't assume the design exists — check the summary), or not_found. Call in a loop until every job is done or error. Surface progress to the user — "Designs are still generating in Subframe…" then "✓ Designs ready, fetching the code now." — so they understand the wait.

You don't need wait_for_jobs when:

• The user came in with an existing Subframe URL (no in-flight job)
• You're only working from id or name and don't need the generated code.

If the user asks to implement immediately after kicking off a design, batch all relevant jobIds into a single wait_for_jobs call (it accepts up to 10).

Inspiration Workflow

Use this workflow when the user chose to use the design as inspiration in an existing non-Subframe project.

1. Wait for any in-flight design jobs — see Awaiting In-Flight Designs.
2. Fetch the design — Use get_page_info with the URL, ID, or name to get the page's layout and structure. If you encounter Subframe components or tokens you're unfamiliar with, use get_component_info to understand a component's props and behavior, or get_theme to see the Subframe project's design tokens (colors, fonts, spacing, shadows).
3. Study existing patterns — Look at the codebase's existing components, styles, and conventions. Identify local equivalents for Subframe components used in the design.
4. Create the page — Implement the design using the codebase's existing UI framework, translating the Subframe layout and component structure into local components and styling.
5. Add business logic — Data fetching, forms, events, loading/error states.

Fetching Designs

Pages are the only resource you fetch into the codebase. Use get_page_info with a URL, ID, or name:

get_page_info({ url: "https://app.subframe.com/PROJECT_ID/design/PAGE_ID/edit" })
get_page_info({ id: "PAGE_ID", projectId: "PROJECT_ID" })
get_page_info({ name: "Settings Page", projectId: "PROJECT_ID" })

To discover what exists in the project, use list_pages, list_components, or list_flows. Snippets aren't synced to code — they live in Subframe as design system references.

Read design documentation alongside the design: get_project_info returns project-level docs (broad principles), and get_component_info returns each component's designDocuments (component-specific usage guidance). Pick these up before implementing so you respect documented constraints.

Get the projectId from .subframe/sync.json. If .subframe/sync.json doesn't exist or doesn't contain a projectId, call list_projects to get the available projects. Each project includes a projectId, name, teamId, and teamName.

• One project: Use it automatically.
• Multiple projects: Always ask the user which project to use. Present each project with its teamName to disambiguate. If the user already mentioned a specific team or project name, match it against the teamName and name fields — but still confirm before proceeding. Never silently pick a project when multiple exist.

Syncing Components

Sync components when they don't exist locally. You can sync specific components by name:

npx @subframe/cli@latest sync Button Alert TextField

Or sync all components:

npx @subframe/cli@latest sync --all

When to sync:

• Components don't exist locally → Sync those specific components before implementing
• Components already exist → Don't sync automatically. If the user wants the latest versions, they'll ask.

Don't modify Button.tsx — Subframe generates and overwrites it on every sync. Each component syncs as a directory:

components/Button/
├─ Button.tsx   // generated by Subframe — overwritten on every sync
└─ index.tsx    // wrapper — re-exports Button.tsx; your code goes here

index.tsx is the import entrypoint (@/ui/components/Button resolves to it). Add wrapping logic there.

Sync Disable

To keep your changes to a file, add // @subframe/sync-disable to the top of it — the CLI skips any file containing this comment:

// @subframe/sync-disable
import { Button as ButtonComponent } from "./Button"
// ... your wrapper

Add it to the wrapper index.tsx once you've customized it. Button.tsx has no marker, so it still receives Subframe's updates. As a last resort you can sync-disable Button.tsx itself, but that freezes the component entirely.

Updating a sync-disabled file:

If a file has @subframe/sync-disable, the sync command skips it. To get the latest version of that file:

1. Use get_component_info to fetch the latest code from Subframe
2. Manually merge the changes with the local modifications

Adding Business Logic

Subframe generates presentational code with placeholder data. You add:

Data fetching:

const { data, isLoading, error } = useQuery(...)

if (isLoading) return <Skeleton />
if (error) return <Alert variant="error">{error.message}</Alert>

return <PageComponent {...data} />

Form handling:

const handleSubmit = async (e: FormEvent) => {
  e.preventDefault()
  await submitForm(formData)
}

Event handlers:

<Button
<Card actionSlot={<IconButton />} />

Dark Mode

If the Subframe project has dark mode enabled, the synced theme uses CSS variables with .dark class overrides. To activate dark mode in the app, set the dark class on the <html> element — using next-themes, a React theme provider context, or any other method.

Updating Existing Pages

When a design changes:

1. Fetch the updated design
2. Update layout/structure from new design
3. Preserve existing hooks, handlers, and state management
4. Sync any new components

When diffing the updated design against the existing code, if there are design changes beyond what the user asked you to design (e.g., layout tweaks, new elements, removed sections), call those out and ask whether to include them.

MCP Tools Reference