Retrieve local session messages

 
 ### Returns
 
-- `data: array of object { id, content, created_at, 3 more }`
+- `data: array of object { id, content, created_at, 4 more }`
 
-  Transcript turns for this page, ordered by `created_at` in the direction selected by the `order` parameter (ascending by default). Turns sharing a `created_at` (all messages of one inference call carry the call's timestamp) are returned in transcript order.
+  Transcript turns for this page, in call order: oldest call first by default, newest call first with `order=desc`. The messages of one call carry the call's timestamp and follow each other in transcript order; a page boundary can fall between them.
 
   - `id: string`
 

 
     When the message was recorded (RFC 3339, UTC)
 
+  - `model: string or null`
+
+    The model that served this assistant turn, as reported in the `model` field of the underlying Messages API response. Null on user messages and on any assistant message whose `provenance` is set: client-asserted history and synthetic markers were not produced by a model during this session, and for unavailable content the serving model is not known.
+
   - `provenance: object { reason, type }  or object { type }  or object { type }  or null`
 
     Where this turn's content came from, discriminated on `type`. Null (the common case) means verified content: on an assistant message, content Claude produced during this session; on a user message, content the user sent. `content_unavailable`: the turn's content cannot be returned and `content` is empty; `reason` says why. `client_asserted`: assistant content the client supplied as conversation history; `content` shows what the model received but its authorship is not verified; never on user-role messages. `synthetic_marker`: a transcript marker the endpoint generated rather than content either party sent during the session. Both `client_asserted` and `synthetic_marker` can result from normal request or client processing, not only client modification. Callers should tolerate unrecognized `type` values.

 
       - `reason: string`
 
-        Why this turn's content cannot be returned, e.g. `not_captured` (the content was not captured for compliance retrieval), `cmek_key_revoked` (the content is encrypted under the organization's customer-managed key and that key is unavailable), `retention_elapsed` (the content lies past the organization's retention boundary; on the placeholder standing in for every pre-boundary turn), or `oversize` (the message exceeds the server's per-message size bound even after per-block truncation). Callers should tolerate unrecognized values. `not_captured` is not proof that no record was stored: content withheld by the storage layer's fail-closed access policies carries the same reason and is deliberately indistinguishable from content that was never captured.
+        Why this turn's content cannot be returned, e.g. `not_captured` (the content was not captured for compliance retrieval), `client_aborted` (the client closed the connection or cancelled the request before the response completed, so the response was not captured for this turn; any partial output already streamed to the client is not included; assistant-role turns only), `cmek_key_revoked` (the content is encrypted under the organization's customer-managed key and that key is unavailable), `retention_elapsed` (the content lies past the organization's retention boundary; on the placeholder standing in for every pre-boundary turn), or `oversize` (the message exceeds the server's per-message size bound even after per-block truncation). Callers should tolerate unrecognized values. `not_captured` is not proof that no record was stored: content withheld by the storage layer's fail-closed access policies carries the same reason and is deliberately indistinguishable from content that was never captured.
 
       - `type: "content_unavailable"`
 

 
   Opaque pagination cursor (prefixed `page_`) for the next page. Null when there is no further page. Treat as an opaque string; the format may change without notice.
 
-- `session: object { id, created_at, organization_uuid, 4 more }`
+- `session: object { id, created_at, organization_uuid, 5 more }`
 
   The local session the messages belong to. `user.email_address` is always null on this endpoint; the messages endpoint does not resolve email addresses.
 

 
     - `"compliance_local_session"`
 
+  - `updated_at: string`
+
+    Timestamp of the session's last retained inference call (RFC 3339, UTC). Always at or after `created_at`. When a session's activity spans the child organization's retention boundary, calls older than the boundary are no longer reflected — but because retention removes only the oldest calls, this value (unlike `created_at`) is unaffected until the entire session has aged out. On the list endpoint this value is a lower bound: for a session still active at a page or `created_at.lt` window boundary it can momentarily lag the session's true last activity. Retrieving the session, or its messages, always reflects the exact latest retained call.
+
   - `user: object { id, email_address }`
 
     The authenticated user at the time of the session. Always set; `user.id` is always populated. `user.email_address` is null when the user's account has been deleted or the user is no longer a member of an organization the key may read.

         }
       ],
       "created_at": "2025-03-12T18:22:41.123456Z",
+      "model": "claude-opus-5",
       "provenance": {
         "reason": "not_captured",
         "type": "content_unavailable"

     "organization_uuid": "a1b2c3d4-e5f6-4789-a012-3456789abcde",
     "product_surface": "cowork",
     "type": "compliance_local_session",
+    "updated_at": "2025-03-12T18:22:41.123456Z",
     "user": {
       "id": "user_01WCz1FkmYMm4gnmykNKUu3Q",
       "email_address": "[email protected]"