chore(perfmon): Update instructions on writing performance docs (#4641)

Author: relaxolotl

src/docs/contributing/approach/sdk-docs/write-performance.mdx

@@ -31,29 +31,42 @@ This file is `index.mdx`. It explains how to install or set up (if appropriate)
 
 To develop content for this file:
 
-1. Determine if the SDK needs an installation step or a property set to enable tracing. If so, add the SDK to `Supported` list in the `<PlatformSection>`, then add a code sample to `performance/enable-tracing/`. If not, add the SDK to `notSupported` list, which will prevent the **Enable Tracing** heading from displaying for this SDK.
+1. If the SDK is still a work-in-progress and is exposed as an experimental or an early access feature, add the platform to the `<PlatformSection>` wrapping the appropriate alert located at the beginning of the content for the page.
 
-2. Add a code sample to `/src/includes/performance/configure-sample-rate/` that covers how to set sample rates.
+1. If the SDK is expected to be used in a high-throughput environment, add the platform to the following `<PlatformSection>` which advises testing before deploying to production. 
 
-3. Determine if you want to have users verify using our custom instrumentation. If so, add the SDK to `Supported` list in the `<PlatformSection>`. If not, add the SDK to `notSupported` list, which will prevent the `<PlatformLink>` to the Custom Instrumentation page from displaying for this SDK.
+1. If automatic instrumentation is still in preview/beta for the SDK, add your platform to the next `<PlatformSection>` that wraps around text that discusses this.
 
-4. Determine if the paragraph regarding pageload and navigation applies to the SDK. If so, add the SDK to `Supported` list in the `<PlatformSection>`. If not, add the SDK to `notSupported` list, which will prevent the content from displaying for this SDK.
+1. If automatic instrumentation is supported, add your platform to the `<PlatformSection>` immediately following **Verify** which advises users to either use auto or custom (or manual) instrumentation to verify the feature. Either omit the platform from the `supported` list or add the platform to the `notSupported` list if auto instrumentation is not available.
 
-5. Determine the level of instrumentation support for verification and add as appropriate to the `Supported` list in the `<PlatformSection>`.
+1. Add a code sample to `/src/includes/performance/configure-sample-rate/` that covers how to set sample rates. Make sure to update `/platforms/common/configuration/sampling.mdx` and **Tracing Options** in `/platforms/common/configuration/options.mdx`.
+
+1. Do one of the following based on whether automatic instrumentation is available for the SDK or not:
+    a. If automatic instrumentation is supported, add your platform to the `<PlatformSection>` immediately following **Verify** which advises users to either use auto or custom (a.k.a. manual) instrumentation to verify the feature. Either omit the platform from `supported` or the platform to `notSupported`.
+
+    b. If automatic instrumentation is not supported, add your platform to the second `<PlatformSection>` after **Verify** which advises users to test out tracing using custom (manual) instrumentation. Omit the platform from the `supported` list or add it to the `notSupported` list if automatic instrumentation is available.
+
+1. Determine if the paragraph regarding pageload and navigation applies to the SDK. If so, add the SDK to the `Supported` list in the `<PlatformSection>`. If not, either omit the platform from the `supported` list or add the platform to the `notSupported` list, which will prevent the content from displaying for this SDK.
 
 ### Custom Instrumentation
 
 We expect this content to apply to all SDKS.
 
 This file is `performance/instrumentation/custom-instrumentation.mdx`. It explains how to manually instrument transactions.
 
+If custom instrumentation for the SDK is exposed as an experimental or an early access feature, add the platform to the `<PlatformSection>` wrapping the appropriate alert located at the beginning of the content for the page.
+
 To develop content for this file, add code samples to these directories:
 
 - `/src/includes/enable-manual-instrumentation/`
 - `/src/includes/performance/add-spans-example/`
 - `/src/includes/performance/retrieve-transaction/`
 
-Then determine whether to provide a code sample illustrating how to connect errors and spans. If so, add the SDK to `Supported` list in the `<PlatformSection>`, then add a code sample `/src/includes/performance/connect-errors-spans/`.
+If any of the above files are not applicable to your platform, find the `<PlatformSection>` wrapping the `<PlatformContent>` pointing to the unsupported file, and add your platform to its `notSupported` list. If such a `<PlatformSection>` doesn't already exist, create one and add your platform to its `notSupported` list.
+
+Then, determine whether to provide a code sample illustrating how to connect errors and spans. If so, add the SDK to the `Supported` list in the appropriate `<PlatformSection>`, then add a code sample `/src/includes/performance/connect-errors-spans/`.
+
+If the platform supports distributed tracing using custom instrumentation, add the SDK to the appropriate `<PlatformSection>` and create an appropriate file at `src/includes/performance/distributed-tracing`.
 
 ### Automatic Instrumentation
 

src/platforms/common/performance/index.mdx

@@ -43,7 +43,7 @@ Performance monitoring is still an experimental, work-in-progress feature, and i
 
 </Note>
 
-</PlatformSection >
+</PlatformSection>
 
 <Note>
 
@@ -77,7 +77,7 @@ Automatic instrumentation for monitoring the performance of your application is
 
 ## Configure the Sample Rate
 
-Once you configure the <PlatformLink to="/configuration/sampling/">sample rate</PlatformLink>, tracing will be enabled in your app. Set the sample rate for your transactions by either:
+Sampling for transactions must also be configured before tracing is be enabled in your app. Set the sample rate for your transactions by either:
 
 1. Setting a uniform sample rate for all transactions using the <PlatformIdentifier name="traces-sample-rate" /> option in your SDK config to a number between `0` and `1`. (For example, to send 20% of transactions, set <PlatformIdentifier name="traces-sample-rate" /> to `0.2`.)
 2. Controlling the sample rate based on the transaction itself and the context in which it's captured, by providing a function to the <PlatformIdentifier name="traces-sampler" /> config option.

src/platforms/common/performance/instrumentation/custom-instrumentation.mdx

@@ -44,7 +44,7 @@ Performance monitoring is still an experimental, work-in-progress feature, and i
 
 </Note>
 
-</PlatformSection >
+</PlatformSection>
 
 To instrument certain regions of your code, you can create transactions to capture them.