# SvelteKit

> Server load versus universal load, and graftRoute on +server.ts.

<Tabs labels="pnpm, npm, bun">

<Tab>

```sh
pnpm add @usegraft/sdk-sveltekit @usegraft/auth @usegraft/mcp
```

</Tab>

<Tab>

```sh
npm i @usegraft/sdk-sveltekit @usegraft/auth @usegraft/mcp
```

</Tab>

<Tab>

```sh
bun add @usegraft/sdk-sveltekit @usegraft/auth @usegraft/mcp
```

</Tab>

</Tabs>

Build the handle in `$lib/server/`, so SvelteKit's server-only enforcement
guards it. The client holds a database handle and must never reach the browser.

## Create the handle

```ts
// src/lib/server/graft.ts
import { DATABASE_URL } from "$env/static/private";
import { createDb } from "@usegraft/db";
import { createGraft } from "@usegraft/sdk-sveltekit";
import { collections } from "../../../graft.config";

export const db = createDb(DATABASE_URL).db;
export const graft = createGraft({ db, collections });
```

Static index instead of Postgres:

```ts
import { openStaticIndex } from "@usegraft/db";

export const graft = createGraft({
  index: await openStaticIndex(".graft/index.db"),
  collections,
});
```

## Read one document

```ts
// src/routes/[slug]/+page.server.ts
import { error } from "@sveltejs/kit";
import { graft } from "$lib/server/graft";
import type { PageServerLoad } from "./$types";

export const load: PageServerLoad = async ({ params }) => {
  const page = await graft.getContent("pages", params.slug);
  if (!page) error(404);
  return { page };
};
```

## Mount functions and MCP

```ts
// src/routes/api/fn/[name]/+server.ts
import { createFunctionsHandler } from "@usegraft/core";
import { graftRoute } from "@usegraft/sdk-sveltekit";
import { functions } from "../../../../graft.config";
import { db } from "$lib/server/graft";

const handler = createFunctionsHandler({ db, functions });

export const POST = graftRoute(handler);
export const GET = graftRoute(handler); // 405s with Allow and a fix
```

```ts
// src/routes/api/mcp/+server.ts
import { createActorResolver } from "@usegraft/auth";
import { createGraftMcpHandler } from "@usegraft/mcp";
import { graftRoute } from "@usegraft/sdk-sveltekit";
import { collections, functions } from "../../../../graft.config";
import { db } from "$lib/server/graft";

const actor = createActorResolver({
  issuers: (process.env.GRAFT_TRUSTED_ISSUERS ?? "")
    .split(/[,\s]+/)
    .filter(Boolean)
    .map((issuer) => ({ issuer })),
  devTokens: process.env.GRAFT_DEV_TOKEN
    ? {
        [process.env.GRAFT_DEV_TOKEN]: {
          kind: "human",
          id: "owner",
          scopes: ["content:write"],
        },
      }
    : undefined,
});

export const POST = graftRoute(
  createGraftMcpHandler({
    contentDir: "./content",
    db,
    collections,
    functions,
    actor,
  }),
);
```

This endpoint serves content writes and asset uploads. JWT verification runs
only when `issuers` is passed; the library does not read
`GRAFT_TRUSTED_ISSUERS` (`graft serve` does). See [Auth](/docs/auth).
Unauthenticated callers get 401. `allowAnonymous: true` is only for a
loopback local server — never on anything reachable from a network. A public
docs surface is [`createDocsMcpHandler`](/docs/docs-mcp), which has no write
tools and no anonymous opt-in.

The parameter is typed structurally as `{ request: Request }`, so this package
needs no `@sveltejs/kit` dependency.

## Cache and invalidation

SvelteKit has no tag-based data cache. Stamp `tagsFor(...)` into a CDN
surrogate-key header with `setHeaders` in `load`, and purge
`tagsForChanges(branch, changeSet)` from your compile webhook.

```ts
import { tagsFor } from "@usegraft/sdk-sveltekit";

export const load: PageServerLoad = async ({ params, setHeaders }) => {
  const page = await graft.getContent("pages", params.slug);
  setHeaders({ "Cache-Tag": tagsFor("main", "pages", params.slug).join(",") });
  return { page };
};
```

`Cache-Tag` is the surrogate-key header. Purge the same strings
`tagsForChanges` returns from your compile webhook.

## The caveat you cannot infer

Read from `+page.server.ts` or `+layout.server.ts`. A **universal** `load` in
`+page.ts` or `+layout.ts` also runs in the browser on client-side navigation,
so a database connection does not belong there — the same care TanStack Start
needs, under different filenames.

`node:sqlite` backs the static index and must stay external to the client
bundle. Keeping the handle in `$lib/server/` is what guarantees that.

See [SDK reference](/docs/sdk-reference) for mounts across adapters and the
honest gaps.