Merge pull request #974 from useautumn/mintlify/changelog-march-16-1773619762

Document explicit customer creation for check and track

apps/docs/mintlify/changelog/changelog.mdx

@@ -4,6 +4,31 @@ mode: "center"
 description: "Some new things we've shipped at Autumn HQ"
 ---
 
+<<<<<<< mintlify/changelog-march-16-1773619762
+<Update label="March 17th 2026">
+  ## Explicit customer creation required for `check` and `track`
+
+  The `/check` and `/track` endpoints no longer auto-create customers. If you call these endpoints with a `customer_id` that doesn't exist, the API now returns a `customer_not_found` error instead of silently creating the customer.
+
+  This change encourages explicit customer lifecycle management and prevents accidental customer creation from typos or stale IDs.
+
+  - **Create customers first**: Call [`customers.getOrCreate`](/documentation/customers/creating-customers) during signup or login before using `check` or `track`
+  - **Handle the error**: If a customer doesn't exist, the API returns error code `customer_not_found`
+
+  ## `autumn-js` SDK 1.0.0
+
+  The `autumn-js` SDK has been promoted from beta to stable at version `1.0.0`.
+
+  <AccordionGroup>
+    <Accordion title="Improvements">
+      - Explicit customer creation required for `check` and `track` endpoints - [#968](https://github.com/useautumn/autumn/pull/968)
+      - `autumn-js` SDK promoted to `1.0.0` stable release - [#968](https://github.com/useautumn/autumn/pull/968)
+    </Accordion>
+  </AccordionGroup>
+</Update>
+
+=======
+>>>>>>> dev
 <Update label="March 16th 2026">
   ## Balance and usage carry-over on plan upgrades
 

apps/docs/mintlify/documentation/customers/check.mdx

@@ -18,6 +18,10 @@ The `allowed` field will return `true` for a given feature if:
 
 Under these conditions, you should allow your customer to use the feature. You can then [record the usage event](/documentation/customers/tracking-usage/) so Autumn can update the `allowed` field as necessary.
 
+<Note>
+The customer must already exist before calling `check`. If the `customer_id` doesn't match an existing customer, the API returns a `customer_not_found` error. Create customers using [`customers.getOrCreate`](/documentation/customers/creating-customers) during signup or login.
+</Note>
+
 ## Checking metered features
 
 Before your customer uses a feature, you can check if the customer is allowed to use it and their current usage.

apps/docs/mintlify/documentation/customers/creating-customers.mdx

@@ -60,6 +60,10 @@ Only the `customerId` field is required — this should be your unique identifie
 A common pattern is to call `customers.getOrCreate` on every login or signup in your application, so Autumn always has the latest customer information.
 </Tip>
 
+<Warning>
+Customers must be created before calling the [`check`](/documentation/customers/check) or [`track`](/documentation/customers/tracking-usage) endpoints. If you call these endpoints with a `customer_id` that doesn't exist, the API will return a `customer_not_found` error. Make sure to call `customers.getOrCreate` during signup or login before checking access or tracking usage.
+</Warning>
+
 ## Pre-creating customers via the dashboard
 
 You can create a customer in the Autumn dashboard before they've ever interacted with your application. This is useful for enterprise or sales-led deals where you want to provision access before the customer signs up.

apps/docs/mintlify/documentation/customers/tracking-usage.mdx

@@ -7,6 +7,10 @@ When customers use features in your product, you'll need to record their usage s
 
 There are two ways to record usage: sending events or setting usage directly.
 
+<Note>
+The customer must already exist before calling `track`. If the `customer_id` doesn't match an existing customer, the API returns a `customer_not_found` error. Create customers using [`customers.getOrCreate`](/documentation/customers/creating-customers) during signup or login.
+</Note>
+
 ## Sending Events
 
 The track route is recommended for tracking consumable features, like AI messages, credits or API calls. Each time a customer uses a feature, send an event to count their usage.