[Containers] Document per-container observability in Wrangler

Document `containers[].observability` for Wrangler Containers.

Add the new container-level observability fields to the Wrangler
configuration reference, including root `observability` fallback,
per-container override behavior, and the targeting fields.

Also update the Containers FAQ and pricing docs to clarify that logs can
be enabled either at the Worker level or per container.

Author: ichernetsky-cf

src/content/changelog/containers/2026-09-08-per-container-observability.mdx

@@ -0,0 +1,39 @@
+---
+title: Configure observability per container application
+description: Set observability for individual container applications in Wrangler.
+products:
+  - containers
+date: 2026-09-18
+---
+
+import { WranglerConfig } from "~/components";
+
+You can now configure observability for each container application when you deploy [Containers](/containers/) with [Wrangler](/workers/wrangler/). This lets you change logging for one container without changing the rest of your Worker.
+
+If you omit `containers[].observability`, Wrangler uses the top-level `observability` setting for that container. If you set it, the container setting overrides the top-level setting.
+
+Use `target_instance_percentage` or `target_instance_count` to apply an observability change to a subset of running instances.
+
+<WranglerConfig>
+
+```jsonc
+{
+	"observability": {
+		"enabled": false,
+	},
+	"containers": [
+		{
+			"class_name": "MyContainer",
+			"image": "./Dockerfile",
+			"observability": {
+				"enabled": true,
+				"target_instance_percentage": 25,
+			},
+		},
+	],
+}
+```
+
+</WranglerConfig>
+
+For more information about Workers Logs, refer to [Workers Logs](/workers/observability/logs/workers-logs/).

src/content/docs/containers/faq.mdx

@@ -12,12 +12,14 @@ import { Render, WranglerConfig } from "~/components";
 
 ## How do Container logs work?
 
-To get logs in the Dashboard, including live tailing of logs, toggle `observability` to true
-in your Worker's wrangler config:
+To get logs in the Dashboard, including live tailing of logs, enable observability in
+your Wrangler config.
+
+You can enable it at the Worker level, which applies to containers by default:
 
 <WranglerConfig>
 
-```json
+```jsonc
 {
 	"observability": {
 		"enabled": true
@@ -27,6 +29,29 @@ in your Worker's wrangler config:
 
 </WranglerConfig>
 
+You can also configure observability per container:
+
+<WranglerConfig>
+
+```jsonc
+{
+	"containers": [
+		{
+			"class_name": "MyContainer",
+			"image": "./Dockerfile",
+			"observability": {
+				"enabled": true
+			}
+		}
+	]
+}
+```
+
+</WranglerConfig>
+
+If a container sets `observability` in its container entry, it overrides the top-level
+`observability` setting for that container.
+
 Logs are subject to the same [limits as Worker logs](/workers/observability/logs/workers-logs/#limits), which means that they are
 retained for 3 days on Free plans and 7 days on Paid plans.
 

src/content/docs/containers/platform/pricing.mdx

@@ -53,4 +53,4 @@ When you use Containers, incoming requests to your containers are handled by you
 
 Containers are integrated with the [Workers Logs](/workers/observability/logs/workers-logs/) platform, and billed at the same rate. Refer to [Workers Logs pricing](/workers/observability/logs/workers-logs/#pricing) for details.
 
-When you [enable observability for your Worker](/workers/observability/logs/workers-logs/#enable-workers-logs) with a binding to a container, logs from your container will show in both the Containers and Observability sections of the Cloudflare dashboard.
+When you [enable observability for your Worker](/workers/observability/logs/workers-logs/#enable-workers-logs), or configure `observability` on a specific container, logs from that container will show in both the Containers and Observability sections of the Cloudflare dashboard.

src/content/docs/workers/wrangler/configuration.mdx

@@ -400,8 +400,10 @@ Example:
 
 The [Observability](/workers/observability/logs/workers-logs) setting allows you to automatically ingest, store, filter, and analyze logging data emitted from Cloudflare Workers directly from your Cloudflare Worker's dashboard.
 
-- `enabled` <Type text="boolean" /> <MetaInfo text="required" />
-  - When set to `true` on a Worker, logs for the Worker are persisted. Defaults to `true` for all new Workers.
+- `enabled` <Type text="boolean" /> <MetaInfo text="optional" />
+  - Shorthand for `logs.enabled`. When set to `true` on a Worker, logs for the Worker are persisted. Defaults to `true` for all new Workers.
+- `logs.enabled` <Type text="boolean" /> <MetaInfo text="optional" />
+  - Whether logs for the Worker are persisted.
 - `head_sampling_rate` <Type text="number" /> <MetaInfo text="optional" />
   - A number between 0 and 1, where 0 indicates zero out of one hundred requests are logged, and 1 indicates every request is logged. If `head_sampling_rate` is unspecified, it is configured to a default value of 1 (100%). Read more about [head-based sampling](/workers/observability/logs/workers-logs/#head-based-sampling).
 
@@ -1305,6 +1307,29 @@ The following options are available:
 - `constraints.jurisdiction` <Type text="string" /> <MetaInfo text="optional" />
   - Restrict containers to compliance boundaries. Valid values: `"eu"`, `"fedramp"`.
 
+- `observability` <Type text="object" /> <MetaInfo text="optional" />
+  - Configures observability for this container application when deploying with `wrangler deploy`.
+  - If omitted, Wrangler uses the top-level [`observability`](#observability) setting as a fallback for that container.
+  - If set, it overrides the top-level `observability` setting for that container.
+
+- `observability.enabled` <Type text="boolean" /> <MetaInfo text="optional" />
+  - Shorthand for `observability.logs.enabled`.
+
+- `observability.logs.enabled` <Type text="boolean" /> <MetaInfo text="optional" />
+  - Whether logs for this container are persisted to Cloudflare's observability platform.
+
+- `observability.target_instance_percentage` <Type text="number" /> <MetaInfo text="optional" />
+  - Apply application-level observability changes to this percentage of running instances.
+  - Must be an integer from `1` to `99`.
+  - Cannot be used with `observability.target_instance_count`.
+  - Requires observability to be enabled for the container.
+
+- `observability.target_instance_count` <Type text="number" /> <MetaInfo text="optional" />
+  - Apply application-level observability changes to this many running instances.
+  - Must be a positive integer.
+  - Cannot be used with `observability.target_instance_percentage`.
+  - Requires observability to be enabled for the container.
+
 <WranglerConfig>
 
 ```jsonc
@@ -1315,6 +1340,10 @@ The following options are available:
 			"image": "./Dockerfile",
 			"max_instances": 10,
 			"instance_type": "basic", // Optional, defaults to "lite"
+			"observability": {
+				"enabled": true,
+				"target_instance_percentage": 25,
+			},
 			"image_vars": {
 				"FOO": "BAR",
 			},