sveltejs/svelte · error · Error

store_invalid_shape

store_invalid_shape

Error message

store_invalid_shape
`${name}` is not a store with a `subscribe` method
https://svelte.dev/e/store_invalid_shape

What it means

Svelte's store contract requires an object with a `subscribe` method (optionally `set`/`update`). When you auto-subscribe with `$store` or pass a value to a store-expecting API, Svelte checks for `subscribe`. If absent, it throws naming the invalid store (`%name%`). Applies to Svelte 4 `$`-prefixed stores and Svelte 5 store interop.

Source

Thrown at packages/svelte/src/internal/shared/errors.js:133

	} else {
		throw new Error(`https://svelte.dev/e/snippet_without_render_tag`);
	}
}

/**
 * `%name%` is not a store with a `subscribe` method
 * @param {string} name
 * @returns {never}
 */
export function store_invalid_shape(name) {
	if (DEV) {
		const error = new Error(`store_invalid_shape\n\`${name}\` is not a store with a \`subscribe\` method\nhttps://svelte.dev/e/store_invalid_shape`);

		error.name = 'Svelte error';

		throw error;
	} else {
		throw new Error(`https://svelte.dev/e/store_invalid_shape`);
	}
}

/**
 * The `this` prop on `<svelte:element>` must be a string, if defined
 * @returns {never}
 */
export function svelte_element_invalid_this_value() {
	if (DEV) {
		const error = new Error(`svelte_element_invalid_this_value\nThe \`this\` prop on \`<svelte:element>\` must be a string, if defined\nhttps://svelte.dev/e/svelte_element_invalid_this_value`);

		error.name = 'Svelte error';

		throw error;
	} else {
		throw new Error(`https://svelte.dev/e/svelte_element_invalid_this_value`);
	}
}

View on GitHub (pinned to 20b341f100)

Solutions

Ensure the variable is a store: wrap with `writable(...)`, `readable(...)`, or `derived(...)`.
If you meant a plain value, remove the `$` prefix.
Verify the store object actually has a `subscribe` function (not overwritten or undefined).

Example fix

// before
let count = 0; // plain value
$: doubled = $count * 2; // $count expects a store -> throws
// after
import { writable } from 'svelte/store';
const count = writable(0);
$: doubled = $count * 2;

Defensive patterns

Strategy: type-guard

Validate before calling

function isStore(v) {
	return v != null && typeof v.subscribe === 'function';
}
if (!isStore(maybeStore)) throw new Error('Expected a store with a subscribe method');

Type guard

function isStore(v) {
	return v != null && typeof v.subscribe === 'function';
}

Prevention

Wrap reactive values in `writable`/`readable` before `$`-subscribing.
Validate store shape before passing to `derived`.
Do not `$`-subscribe plain variables.
Check for `undefined` stores from failed imports.

When it happens

Trigger: Using `$value` where `value` is not a store (plain object, array, primitive); passing a non-store to `derived()`; a store whose `subscribe` was deleted/renamed; auto-subscribing an `undefined` variable.

Common situations: Forgetting to wrap a value in `writable()`/`readable()`; passing a plain object where a store is expected; SSR/import issues yielding `undefined`; refactoring that drops the store wrapper.

Related errors

AI-assisted analysis of sveltejs/svelte@20b341f100 (2026-08-12). Data as JSON: /api/errors/03f5e00284bf0b21. Report an issue: GitHub.