docs(qstash): document optional token and Client.fromEnv

llms-full.txt

@@ -15592,6 +15592,29 @@ const client = new Client({
 });
 ```
 
+The token is optional. If you leave it out, the client reads `QSTASH_TOKEN`,
+`QSTASH_URL` and their [region-prefixed variants](/docs/qstash/howto/multi-region)
+from the environment, and only warns when it finds nothing:
+
+```typescript
+const client = new Client();
+```
+
+Use `Client.fromEnv()` if you would rather fail fast:
+
+```typescript
+const client = Client.fromEnv();
+// throws: [Upstash QStash] Unable to find environment variable: QSTASH_TOKEN.
+```
+
+<Note>
+  `fromEnv` reads `process.env`, so on runtimes where credentials only exist as
+  bindings (Cloudflare Workers) pass the token to `new Client()` instead.
+</Note>
+
+No credentials at all? You don't need any while developing — see
+[Local development](#local-development) below.
+
 #### RetryConfig
 
 You can configure the retry policy of the client by passing the configuration to the client constructor.

qstash/sdks/ts/gettingstarted.mdx

@@ -24,6 +24,29 @@ const client = new Client({
 });
 ```
 
+The token is optional. If you leave it out, the client reads `QSTASH_TOKEN`,
+`QSTASH_URL` and their [region-prefixed variants](/qstash/howto/multi-region)
+from the environment, and only warns when it finds nothing:
+
+```typescript
+const client = new Client();
+```
+
+Use `Client.fromEnv()` if you would rather fail fast:
+
+```typescript
+const client = Client.fromEnv();
+// throws: [Upstash QStash] Unable to find environment variable: QSTASH_TOKEN.
+```
+
+<Note>
+  `fromEnv` reads `process.env`, so on runtimes where credentials only exist as
+  bindings (Cloudflare Workers) pass the token to `new Client()` instead.
+</Note>
+
+No credentials at all? You don't need any while developing — see
+[Local development](#local-development) below.
+
 #### RetryConfig
 
 You can configure the retry policy of the client by passing the configuration to the client constructor.