Document concurrency limits, queue status endpoint, maxConcurrency param

- openapi.json: maxConcurrency on ReadRequest, GET /v1/queue/status endpoint
- queue-status.mdx: API reference for queue status with concurrency limits table
- read.mdx: concurrency section with maxConcurrency docs
- mint.json: queue-status page in navigation

Author: nihalwashere

api-reference/account/queue-status.mdx

@@ -0,0 +1,39 @@
+---
+title: "Queue status"
+openapi: "openapi.json GET /v1/queue/status"
+---
+
+Check how many browser slots your workspace is currently using, how many jobs are waiting, and your plan's concurrency limit.
+
+Use this to monitor your queue before submitting large batch jobs, or to build dashboards that show real-time scraping activity.
+
+```bash
+curl https://api.reader.dev/v1/queue/status \
+  -H "x-api-key: $READER_KEY"
+```
+
+## Concurrency limits
+
+Each plan has a maximum number of concurrent browser slots:
+
+| Plan | Concurrent browsers |
+| --- | --- |
+| Free | 2 |
+| Pro | 10 |
+| Business | 50 |
+| Enterprise | 200 |
+
+When all your browser slots are in use, new sync scrape requests return `429` with a `Retry-After` header. Async jobs (batch, crawl) queue and wait for a slot to open.
+
+## Per-request concurrency cap
+
+Pass `maxConcurrency` in your `/v1/read` request to limit how many browser slots a single batch or crawl job uses. This prevents one large job from consuming all your slots.
+
+```bash
+curl -X POST https://api.reader.dev/v1/read \
+  -H "x-api-key: $READER_KEY" \
+  -d '{
+    "urls": ["url1", "url2", "...100 more..."],
+    "maxConcurrency": 5
+  }'
+```

api-reference/read.mdx

@@ -15,6 +15,12 @@ See [The read primitive](/home/concepts/read-primitive) for a narrative overview
 
 Set `proxyMode` to `"standard"` (1 credit, fast, default) or `"premium"` (3 credits, residential proxies, bypasses bot walls). The response metadata tells you which mode ran. See [Proxy modes](/home/concepts/proxy-modes).
 
+## Concurrency
+
+Set `maxConcurrency` to limit how many browser slots a batch or crawl job uses. Prevents one large job from consuming all your plan's concurrent browser slots. Capped to your plan's limit.
+
+Check your current usage with [Queue status](/api-reference/account/queue-status).
+
 ## Idempotency
 
 Pass an `x-idempotency-key` header to deduplicate retried POSTs. Reader caches the original response for 24 hours and returns it verbatim on any subsequent request with the same key.

mint.json

@@ -195,7 +195,8 @@
       "group": "Account",
       "pages": [
         "api-reference/account/credits",
-        "api-reference/account/history"
+        "api-reference/account/history",
+        "api-reference/account/queue-status"
       ]
     },
     {

openapi.json

@@ -342,6 +342,11 @@
             "minimum": 1,
             "maximum": 20
           },
+          "maxConcurrency": {
+            "type": "integer",
+            "minimum": 1,
+            "description": "Max concurrent browser slots for this request. Capped to your plan's limit."
+          },
           "maxDepth": {
             "type": "integer",
             "minimum": 1,
@@ -2195,6 +2200,57 @@
         }
       }
     },
+    "/v1/queue/status": {
+      "get": {
+        "summary": "Get queue status",
+        "description": "Returns the workspace's concurrency state: active browser slots in use, waiting jobs, and the plan's max concurrency.",
+        "tags": [
+          "Account"
+        ],
+        "security": [
+          {
+            "ApiKeyAuth": []
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Queue status",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "type": "object",
+                  "properties": {
+                    "success": {
+                      "type": "boolean",
+                      "enum": [true]
+                    },
+                    "data": {
+                      "type": "object",
+                      "properties": {
+                        "activeJobs": {
+                          "type": "integer",
+                          "description": "Number of browser slots currently in use"
+                        },
+                        "waitingJobs": {
+                          "type": "integer",
+                          "description": "Number of jobs waiting in the queue"
+                        },
+                        "maxConcurrency": {
+                          "type": "integer",
+                          "description": "Maximum concurrent browser slots for your plan"
+                        }
+                      },
+                      "required": ["activeJobs", "waitingJobs", "maxConcurrency"]
+                    }
+                  },
+                  "required": ["success", "data"]
+                }
+              }
+            }
+          }
+        }
+      }
+    },
     "/v1/usage/history": {
       "get": {
         "summary": "List usage history",