Generate custom widget

ESCAPE HATCH — use this ONLY when a native widget spec (propose_insight_widget / author_widget) genuinely cannot express the UI; a validated native kind is always preferred (it renders in-process, no sandbox cost). When you do generate: write a React component in TS/JSX. Style with TAILWIND utility classes (just `className="..."` — the runtime JITs them, no config) and shadcn/ui-style components built on the vendored Radix primitives. Import ONLY: `@banksync/widget-sdk` (defineWidget, useData, useDataset, useSettings, useSetting, useFilters, useTheme, brokerFetch, emitFilter, openUrl), React, `recharts` (charts), `lucide-react` (icons), and the vendored libs (clsx, tailwind-merge, class-variance-authority, @radix-ui/react-*, d3-*, date-fns, zod). DESIGN — the widget must look BEAUTIFUL and FILL its dashboard tile (the user sizes the cell; the widget fills it responsively, like a chart). Give the ROOT `className="flex h-full flex-col gap-4 p-5 ..."`. Use the THEME-AWARE shadcn semantic colors (bg-card, text-card-foreground, text-muted-foreground, border, bg-primary/10, text-primary) so it adapts to light/dark automatically — avoid hard-coded black/white; give it a clear header (an icon in a rounded bg-primary/10 tile + a title), generous padding/gap, and rounded corners. For charts use recharts in a `<ResponsiveContainer width="100%" height="100%">` inside a `min-h-0 flex-1` box so the chart GROWS to fill; prefer a donut (innerRadius) with the total centered in the hole, rounded slices, and a legend with values + %. NO network (fetch), storage (localStorage), or frame access — those are rejected with correctable, line-anchored errors (fix and retry, max 2). Read the widget-SDK docs (search_docs) for the API + examples. Supply a complete portable manifest declaring every named input, widget-local field, setting, capability, and allowed network origin. Use `useDataset(inputId)` for data and `useSettings()`/`useSetting()` for configuration; `useData()` is legacy-v1 only. The source is compiled to a hash-pinned sandboxed build and returned as an INERT package proposal — safe to call speculatively. It does not create an installation, choose a bank/feed, or grant access; the user continues through the normal configure and approval flow.

Parameters

Example call

The tool call an MCP client sends (required arguments shown with placeholder values).

{
  "tool": "generate_custom_widget",
  "arguments": {
    "source": "value",
    "manifest": "value"
  }
}

Use this tool in