Add docs for messages view

Author: katmayb

src/docs.json

@@ -383,6 +383,7 @@
                 {
                   "group": "Viewing & managing traces",
                   "pages": [
+                    "langsmith/view-trace",
                     "langsmith/filter-traces-in-application",
                     "langsmith/configure-input-output-preview",
                     "langsmith/manage-trace",

src/langsmith/annotation-queues.mdx

@@ -95,7 +95,7 @@ Because of these settings, the number of runs visible to each reviewer can diffe
 
 There are several ways to populate a single-run queue with work items:
 
-- **From a trace view**: Click **Add to Annotation Queue** in the top-right corner of any [trace](/langsmith/observability-concepts#traces) view. You can add any intermediate [run](/langsmith/observability-concepts#runs), but not the root span.
+- **From the Details view**: Click **Add to Annotation Queue** in the top-right corner of any trace. You can add any intermediate [run](/langsmith/observability-concepts#runs), but not the root span.
 
     ![Trace view with the Add to Annotation Queue button highlighted at the top of the screen.](/langsmith/images/add-to-annotation-queue.png)
 
@@ -164,7 +164,7 @@ Selecting two experiments and creating a PAQ automatically pairs the runs. When
 1. Optional actions:
     - Leave comments tied to either run.
     - Requeue the comparison if you need to revisit it later.
-    - Open the full trace view for deeper debugging.
+    - Open the Details view for deeper debugging.
 
 Reservations, reviewer thresholds, and comments behave identically to those in single-run queues, enabling teams to use different queue types without modifying their existing workflow.
 

src/langsmith/filter-traces-in-application.mdx

@@ -329,9 +329,9 @@ To copy the filter:
 
 For more information on the query language syntax, refer to the [Trace query syntax](/langsmith/trace-query-syntax#filter-query-language).
 
-## Filter runs within the trace view
+## Filter runs in the Details view
 
-You can also apply filters directly within the trace view, which is useful for sifting through traces with a large number of runs. The same filters available in the main runs table view can be applied here.
+You can also apply filters directly in the Details view, which is useful for sifting through traces with a large number of runs. The same filters available in the main runs table view can be applied here.
 
 By default, only the runs that match the filters will be shown. To see the matched runs within the broader context of the trace tree, switch the view option from "Filtered Only" to "Show All" or "Most relevant".
 
@@ -351,7 +351,7 @@ By default, only the runs that match the filters will be shown. To see the match
 
 If you have [copied a previously constructed filter](#copy-a-filter), you may want to manually apply this raw query in a future session.
 
-In order to do this, you can click on **Switch to raw query** on the bottom of the filters popover in the trace view. From there you can paste a raw query into the text box.
+In order to do this, you can click on **Switch to raw query** on the bottom of the filters popover in the Details view. From there you can paste a raw query into the text box.
 
 <Note>
 This will add that query to the existing queries, not overwrite it.

src/langsmith/manage-trace.mdx

@@ -1,9 +1,9 @@
 ---
 title: Manage a trace
-description: Compare traces side-by-side, share traces publicly, and view server logs from the trace view in LangSmith.
+description: Compare traces side-by-side, share traces publicly, and view server logs from the Details view in LangSmith.
 ---
 
-From the trace view, you can [compare two traces](#compare-traces) side-by-side, [share a trace publicly](#share-a-trace), and [view the server logs](#view-server-logs) associated with a trace execution.
+From the Details view, you can [compare two traces](#compare-traces) side-by-side, [share a trace publicly](#share-a-trace), and [view the server logs](#view-server-logs) associated with a trace execution.
 
 ## Compare traces
 
@@ -25,14 +25,14 @@ If your [self-hosted](/langsmith/self-hosted) or [hybrid](/langsmith/hybrid) Lan
 To share a trace publicly:
 
 1. Open any trace in the [UI](https://smith.langchain.com).
-1. Click the **Share** button in the more <Icon icon="dots-vertical" /> menu at the top of the trace view.
+1. Click the **Share** button in the more <Icon icon="dots-vertical" /> menu at the top of the Details view.
 1. In the dialog that appears, copy the public link.
 
 Shared traces are accessible to anyone with the link, even without a LangSmith account. They can view the trace but not edit it.
 
 To unshare a trace, use either of the following methods:
 
-1. Open the shared trace, click **Public** in the toolbar at the top of the trace view, then click **Unshare** in the dialog.
+1. Open the shared trace, click **Public** in the toolbar at the top of the Details view, then click **Unshare** in the dialog.
 1. Go to **Settings** → **Shared URLs** to view all publicly shared traces in the selected workspace. Click **Unshare** next to the trace you want to unshare.
 
 ## View server logs
@@ -41,9 +41,9 @@ To unshare a trace, use either of the following methods:
 Viewing server logs for a trace only works with the [Cloud SaaS](/langsmith/cloud) and [fully self-hosted](/langsmith/self-hosted) deployment options.
 </Note>
 
-When viewing a trace that was generated by a run in LangSmith, you can access the associated server logs directly from the trace view.
+When viewing a trace that was generated by a run in LangSmith, you can access the associated server logs directly from the Details view.
 
-In the trace view, use the **See Logs** button in the top right corner, next to the **Run in Studio** button.
+In the Details view, use the **See Logs** button in the top right corner, next to the **Run in Studio** button.
 
 Clicking this button will take you to the server logs view for the associated deployment in LangSmith.
 
@@ -61,7 +61,7 @@ The server logs view displays logs from both:
     logger.info("Your log message");
     ```
 
-When you navigate from the trace view, the **Filters** box will automatically pre-fill with the Trace ID from the trace you just viewed, so you can quickly filter the logs to see only those related to your specific trace execution.
+When you navigate from the Details view, the **Filters** box will automatically pre-fill with the Trace ID from the trace you just viewed, so you can quickly filter the logs to see only those related to your specific trace execution.
 
 ![Deployment server logs filters](/langsmith/images/lgp-server-logs-filters.png)
 

src/langsmith/observability-quickstart.mdx

@@ -157,7 +157,7 @@ npx tsx index.ts
 
 ## 4. View your trace
 
-In the [LangSmith UI](https://smith.langchain.com), go to **Tracing** and select your **default** project. Click the `assistant` row to open the **Trace** details panel, which shows the `assistant` function with the `get_context` tool call and the OpenAI call nested inside it.
+In the [LangSmith UI](https://smith.langchain.com), go to **Tracing** and select your **default** project. Click the `assistant` row to open the trace. The **Messages** tab shows the conversation as it was sent to the model. Select the **Details** tab to see the full run tree, including the `assistant` function with the `get_context` tool call and the OpenAI call nested inside it.
 
 <img
     className="block dark:hidden"

src/langsmith/threads.mdx

@@ -288,7 +288,7 @@ You can then click into a particular thread. This will open the history for a pa
 Threads can be viewed in two different ways:
 
 - [Thread overview](/langsmith/threads#thread-overview)
-- [Trace view](/langsmith/threads#trace-view)
+- [Details view](/langsmith/threads#details-view)
 
 You can use the buttons at the top of the page to switch between the two views or use the keyboard shortcut `T` to toggle between the two views.
 
@@ -299,9 +299,9 @@ The thread overview displays each turn of the conversation sequentially, showing
 The JSON path for the inputs and outputs supports negative indexing, so you can use `-1` to access the last element of an array. For example, `inputs.messages[-1].content` will access the last message in the `messages` array.
 
 
-#### Trace view
+#### Details view
 
-The trace view here is similar to the trace view when looking at a single run, except that you have easy access to all the runs for each turn in the thread.
+The Details view here is the same as the Details view for an individual trace, giving you access to all the runs for each turn in the thread.
 
 ### View feedback
 

src/langsmith/view-trace.mdx

@@ -0,0 +1,58 @@
+---
+title: View a trace
+description: Inspect a trace in LangSmith using the Messages view or Details view.
+---
+
+When you open a trace in the [LangSmith UI](https://smith.langchain.com), two views are available at the top of the trace panel:
+
+- [**Messages**](#messages-view): Renders a trace as a readable conversation, showing the sequence of messages exchanged between the user, assistant, and any tools called.
+- [**Details**](#details-view): Shows the complete technical record of a trace, including every run with its inputs, outputs, timing, token counts, and metadata.
+
+## Messages view
+
+The Messages view is the **default view** for traces under 20 MB.
+
+<Note>
+LangSmith does not display the Messages view for traces larger than 20 MB. On [self-hosted](/langsmith/self-hosted) deployments, this limit is configurable via environment variable.
+</Note>
+
+Use the Messages view to understand what happened in an agent interaction quickly: what the user asked, how the assistant responded, and which tools the agent invoked.
+
+### Customize the Messages view
+
+You can control how runs appear in the Messages view using metadata keys on individual runs.
+
+- `ls_agent_type`: Accepts `agent`, `subagent`, or `middleware`. Used to filter middleware runs from the Messages view and to control how subagent details are displayed.
+
+- `ls_message_view_exclude`: Set to `true` to exclude a run and all runs in its subtree from the Messages view.
+
+    ```python
+    @traceable(metadata={"ls_message_view_exclude": True})
+    def my_run():
+        ...
+    ```
+
+### Provider-specific behavior
+
+The messages shown in the Messages view depend on the integration:
+
+| **Integration** | **Messages shown** |
+|-------------|---------------|
+| Anthropic / Claude SDK | Messages from the current trace only |
+| DeepAgents / OpenAI | Messages from the current trace and ancestor traces |
+
+## Details view
+
+Use the Details view to debug execution: inspect a specific LLM call, review tool inputs and outputs, or identify where an error occurred.
+
+### Customize the Details view
+
+Setting `run_type="llm"` on a run causes the Details view to render token counts and latency for that run. See [Log an LLM trace](/langsmith/log-llm-trace) for the full message format specification.
+
+### Actions
+
+From the Details view, you can also:
+
+- **Compare traces**: Select two traces to open a side-by-side comparison. See [Manage a trace](/langsmith/manage-trace#compare-traces).
+- **Share a trace**: Generate a public link to the trace. See [Manage a trace](/langsmith/manage-trace#share-a-trace).
+- **View server logs**: Access server logs associated with a trace generated by a LangSmith deployment. See [Manage a trace](/langsmith/manage-trace#view-server-logs).