create

 
               - `"search_result_location"`
 
-      - `ImageBlockParam object { source, type, cache_control }`
-
-        - `source: Base64ImageSource or URLImageSource`
+      - `ImageBlockParam object { source, type, cache_control, transformations }`
+
+        - `source: Base64ImageSource or URLImageSource or FileImageSource`
 
           - `Base64ImageSource object { data, media_type, type }`
 

 
             - `url: string`
 
+          - `FileImageSource object { file_id, type }`
+
+            - `file_id: string`
+
+            - `type: "file"`
+
+              - `"file"`
+
         - `type: "image"`
 
           - `"image"`

 
           Create a cache control breakpoint at this content block.
 
+        - `transformations: optional ImageTransformationsParam or null`
+
+          Configures the transformations the server applies to this image before the model observes it. Each key names a condition the server transforms images for; its value selects the transformation applied. Omitted keys keep their default behavior, and an empty object is equivalent to omitting the field.
+
+          - `oversized_image: optional "downsize" or "error"`
+
+            What the server does when this image exceeds the model's maximum image size. `"downsize"` (the default) scales the image down to fit, which changes the dimensions the model observes without telling you. `"error"` instead rejects the request with a 400 error naming the image's dimensions and the largest dimensions that fit, so you can scale the image deliberately — your image is never silently scaled down.
+
+            - `"downsize"`
+
+            - `"error"`
+
       - `DocumentBlockParam object { source, type, cache_control, 3 more }`
 
-        - `source: Base64PDFSource or PlainTextSource or ContentBlockSource or URLPDFSource`
+        - `source: Base64PDFSource or PlainTextSource or ContentBlockSource or 2 more`
 
           - `Base64PDFSource object { data, media_type, type }`
 

 
                 - `TextBlockParam object { text, type, cache_control, citations }`
 
-                - `ImageBlockParam object { source, type, cache_control }`
+                - `ImageBlockParam object { source, type, cache_control, transformations }`
 
             - `type: "content"`
 

 
             - `url: string`
 
+          - `FileDocumentSource object { file_id, type }`
+
+            - `file_id: string`
+
+            - `type: "file"`
+
+              - `"file"`
+
         - `type: "document"`
 
           - `"document"`

 
           - `"redacted_thinking"`
 
-      - `ToolUseBlockParam object { id, input, name, 3 more }`
+      - `ToolUseBlockParam object { id, input, name, 4 more }`
 
         - `id: string`
 

 
               - `"code_execution_20260120"`
 
-      - `ToolResultBlockParam object { tool_use_id, type, cache_control, 2 more }`
+        - `toolset_name: optional string or null`
+
+          For a toolset member tool_use, the toolset family this member belongs to.
+
+      - `ToolResultBlockParam object { tool_use_id, type, cache_control, 3 more }`
 
         - `tool_use_id: string`
 

 
           Create a cache control breakpoint at this content block.
 
-        - `content: optional string or array of TextBlockParam or ImageBlockParam or SearchResultBlockParam or 2 more`
+        - `content: optional string or array of TextBlockParam or ImageBlockParam or SearchResultBlockParam or 3 more`
 
           - `string`
 
-          - `array of TextBlockParam or ImageBlockParam or SearchResultBlockParam or 2 more`
+          - `array of TextBlockParam or ImageBlockParam or SearchResultBlockParam or 3 more`
 
             - `TextBlockParam object { text, type, cache_control, citations }`
 
-            - `ImageBlockParam object { source, type, cache_control }`
+            - `ImageBlockParam object { source, type, cache_control, transformations }`
 
             - `SearchResultBlockParam object { content, source, title, 3 more }`
 

 
                 Create a cache control breakpoint at this content block.
 
+            - `BrowserStateBlockParam object { tabs, type, cache_control, state_changes }`
+
+              The caller's browser state after a browser toolset member call —
+              the full inventory of open tabs, which tab is active, and any side
+              effects (tabs opened, download state changes) the call produced.
+
+              At most one per `tool_result`, only on a non-error result answering a
+              browser toolset member `tool_use`. The server renders the
+              model-visible text from it; the model never sees the raw fields.
+
+              - `tabs: array of BrowserStateTabEntry`
+
+                All tabs open in the browser after this call — the full inventory, not a delta. May be empty. Whenever non-empty, exactly one entry carries `active: true`.
+
+                - `tab_id: string`
+
+                  The caller-assigned identifier for this tab, unique within the inventory.
+
+                - `title: string`
+
+                  The title of the page the tab is showing. May be empty.
+
+                - `url: string`
+
+                  The URL of the page the tab is showing. May be empty.
+
+                - `active: optional boolean`
+
+                  Whether this tab is the active tab after this call. Whenever `tabs` is non-empty, exactly one entry is marked `active: true`.
+
+              - `type: "browser_state"`
+
+                - `"browser_state"`
+
+              - `cache_control: optional CacheControlEphemeral or null`
+
+                Create a cache control breakpoint at this content block.
+
+              - `state_changes: optional array of BrowserStateChange or null`
+
+                Tabs opened and download state changes during this call. "Nothing to report" is expressed by omitting the field, never by an empty list.
+
+                - `BrowserStateChangeTabOpened object { tab_id, type }`
+
+                  A tab this call's execution opened that remains open at its end —
+                  the creation delta of the `tabs` inventory, not an event log.
+
+                  Carries only the `tab_id`; the tab's `title` and `url` live on its
+                  `tabs` entry, which must include the same `tab_id`. A tab opened
+                  during a failed call gets no deferred `tab_opened`; it simply appears
+                  in the next result's `tabs` inventory.
+
+                  - `tab_id: string`
+
+                    The `tab_id` of the opened tab, present in `tabs`.
+
+                  - `type: "tab_opened"`
+
+                    - `"tab_opened"`
+
+                - `BrowserStateChangeDownloadStarted object { download_id, type, url }`
+
+                  A file download that started during this call.
+
+                  - `download_id: string`
+
+                    The caller-assigned identifier for this download, stable across the state changes reporting it.
+
+                  - `type: "download_started"`
+
+                    - `"download_started"`
+
+                  - `url: string`
+
+                    The final post-redirect URL the download was served from.
+
+                - `BrowserStateChangeDownloadCompleted object { download_id, type, url, 2 more }`
+
+                  A file download that finished during this call, reported with the
+                  same `download_id` as its `download_started` — or without a prior
+                  `download_started`, when the download finished during the call that
+                  started it (at most one state change per `download_id` per result).
+
+                  - `download_id: string`
+
+                    The caller-assigned identifier for this download, stable across the state changes reporting it.
+
+                  - `type: "download_completed"`
+
+                    - `"download_completed"`
+
+                  - `url: string`
+
+                    The final post-redirect URL the download was served from.
+
+                  - `path: optional string or null`
+
+                    Where the executor saved the file, on the executor's filesystem. Only included when another tool in the same environment can read the file at that path.
+
+                  - `size_bytes: optional number or null`
+
+                    The completed download's size.
+
+                - `BrowserStateChangeDownloadFailed object { download_id, type, url, error }`
+
+                  A file download that failed — or was cancelled — during this call.
+
+                  - `download_id: string`
+
+                    The caller-assigned identifier for this download, stable across the state changes reporting it.
+
+                  - `type: "download_failed"`
+
+                    - `"download_failed"`
+
+                  - `url: string`
+
+                    The final post-redirect URL the download was served from.
+
+                  - `error: optional string or null`
+
+                    The failure or cancellation detail, when known.
+
         - `is_error: optional boolean`
+
+        - `toolset_name: optional string or null`
+
+          For a toolset member tool_result, the toolset family of the paired tool_use.
 
       - `ServerToolUseBlockParam object { id, input, name, 3 more }`
 

 
           Create a cache control breakpoint at this content block.
 
-      - `MidConversationSystemBlockParam object { content, type, cache_control }`
-
-        System instructions that appear mid-conversation.
-
-        Use this block to provide or update system-level instructions at a specific
-        point in the conversation, rather than only via the top-level `system` parameter.
-
-        - `content: array of TextBlockParam`
-
-          System instruction text blocks.
-
-          - `text: string`
-
-          - `type: "text"`
-
-          - `cache_control: optional CacheControlEphemeral or null`
-
-            Create a cache control breakpoint at this content block.
-
-          - `citations: optional array of TextCitationParam or null`
-
-        - `type: "mid_conv_system"`
-
-          - `"mid_conv_system"`
-
-        - `cache_control: optional CacheControlEphemeral or null`
-
-          Create a cache control breakpoint at this content block.
-
   - `role: "user" or "assistant" or "system"`
 
     - `"user"`

 
   Top-level cache control automatically applies a cache_control marker to the last cacheable block in the request.
 
-- `container: optional string or null`
+- `container: optional MessageCreateParamsContainer or null`
 
   Container identifier for reuse across requests.
+
+  - `ContainerParams object { id, skills }`
+
+    Container parameters with skills to be loaded.
+
+    - `id: optional string or null`
+
+      Container id
+
+    - `skills: optional array of SkillParams or null`
+
+      List of skills to load in the container
+
+      - `skill_id: string`
+
+        Skill ID
+
+      - `type: "anthropic" or "custom"`
+
+        Type of skill - either 'anthropic' (built-in) or 'custom' (user-defined)
+
+        - `"anthropic"`
+
+        - `"custom"`
+
+      - `version: optional string`
+
+        Skill version or 'latest' for most recent version
+
+  - `string`
 
 - `inference_geo: optional string or null`
 

 
       When true, guarantees schema validation on tool names and inputs
 
+  - `BrowserToolset20260801 object { type, allowed_callers, cache_control, configs }`
+
+    The browser toolset: a single `tools[]` entry (carrying no
+    `name`) that declares the browser tool family. The model is served
+    the family's tool with any members disabled via `configs` removed
+    from its schema.
+
+    - `type: "browser_toolset_20260801"`
+
+      - `"browser_toolset_20260801"`
+
+    - `allowed_callers: optional array of "direct" or "code_execution_20250825" or "code_execution_20260120" or "code_execution_20260521"`
+
+      - `"direct"`
+
+      - `"code_execution_20250825"`
+
+      - `"code_execution_20260120"`
+
+      - `"code_execution_20260521"`
+
+    - `cache_control: optional CacheControlEphemeral or null`
+
+      Create a cache control breakpoint at this content block.
+
+    - `configs: optional BrowserToolsetConfigs or null`
+
+      Per-member configuration for `browser_toolset_20260801`: one
+      optional field per member tool, keyed by the member name — the same
+      name the member's `tool_use` blocks carry. Every member is an
+      accepted key, and a member's defaults apply wherever its key is
+      absent. Unknown keys are rejected: the field set is this toolset
+      version's complete member set.
+
+      - `close_tab: optional BrowserCloseTabConfig or null`
+
+        `close_tab`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `double_click: optional BrowserDoubleClickConfig or null`
+
+        `double_click`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `file_upload: optional BrowserFileUploadConfig or null`
+
+        `file_upload`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `find: optional BrowserFindConfig or null`
+
+        `find`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `form_input: optional BrowserFormInputConfig or null`
+
+        `form_input`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `get_page_text: optional BrowserGetPageTextConfig or null`
+
+        `get_page_text`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `hold_key: optional BrowserHoldKeyConfig or null`
+
+        `hold_key`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `hover: optional BrowserHoverConfig or null`
+
+        `hover`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `javascript_exec: optional BrowserJavascriptExecConfig or null`
+
+        `javascript_exec`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `key: optional BrowserKeyConfig or null`
+
+        `key`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `left_click: optional BrowserLeftClickConfig or null`
+
+        `left_click`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `left_click_drag: optional BrowserLeftClickDragConfig or null`
+
+        `left_click_drag`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `left_mouse_down: optional BrowserLeftMouseDownConfig or null`
+
+        `left_mouse_down`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `left_mouse_up: optional BrowserLeftMouseUpConfig or null`
+
+        `left_mouse_up`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `list_tabs: optional BrowserListTabsConfig or null`
+
+        `list_tabs`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `middle_click: optional BrowserMiddleClickConfig or null`
+
+        `middle_click`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `mouse_move: optional BrowserMouseMoveConfig or null`
+
+        `mouse_move`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `navigate: optional BrowserNavigateConfig or null`
+
+        `navigate`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `new_tab: optional BrowserNewTabConfig or null`
+
+        `new_tab`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `read_console: optional BrowserReadConsoleConfig or null`
+
+        `read_console`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `read_network: optional BrowserReadNetworkConfig or null`
+
+        `read_network`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `read_page: optional BrowserReadPageConfig or null`
+
+        `read_page`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `right_click: optional BrowserRightClickConfig or null`
+
+        `right_click`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `screenshot: optional BrowserScreenshotConfig or null`
+
+        `screenshot`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `scroll: optional BrowserScrollConfig or null`
+
+        `scroll`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `scroll_to: optional BrowserScrollToConfig or null`
+
+        `scroll_to`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `switch_tab: optional BrowserSwitchTabConfig or null`
+
+        `switch_tab`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `triple_click: optional BrowserTripleClickConfig or null`
+
+        `triple_click`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `type: optional BrowserTypeConfig or null`
+
+        `type`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `wait: optional BrowserWaitConfig or null`
+
+        `wait`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `zoom: optional BrowserZoomConfig or null`
+
+        `zoom`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
   - `MemoryTool20250818 object { name, type, allowed_callers, 4 more }`
 
     - `name: "memory"`

 
       When true, guarantees schema validation on tool names and inputs
 
+  - `ComputerToolset20260801 object { type, allowed_callers, cache_control, configs }`
+
+    The computer toolset: a single `tools[]` entry (carrying no
+    `name`) that declares the computer tool family. The model is
+    served the family's tool with any members disabled via `configs`
+    removed from its schema. Every member is enabled by default, zoom
+    included. The single-tool options `display_number` and
+    `enable_zoom` are not fields of a toolset entry — it carries only
+    `type`, `configs`, and `cache_control`; zoom is controlled
+    via `configs.zoom.enabled`.
+
+    - `type: "computer_toolset_20260801"`
+
+      - `"computer_toolset_20260801"`
+
+    - `allowed_callers: optional array of "direct" or "code_execution_20250825" or "code_execution_20260120" or "code_execution_20260521"`
+
+      - `"direct"`
+
+      - `"code_execution_20250825"`
+
+      - `"code_execution_20260120"`
+
+      - `"code_execution_20260521"`
+
+    - `cache_control: optional CacheControlEphemeral or null`
+
+      Create a cache control breakpoint at this content block.
+
+    - `configs: optional ComputerToolsetConfigs or null`
+
+      Per-member configuration for `computer_toolset_20260801`: one
+      optional field per member tool, keyed by the member name — the same
+      name the member's `tool_use` blocks carry. Every member is an
+      accepted key, and a member's defaults apply wherever its key is
+      absent. Unknown keys are rejected: the field set is this toolset
+      version's complete member set.
+
+      - `cursor_position: optional ComputerCursorPositionConfig or null`
+
+        `cursor_position`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `double_click: optional ComputerDoubleClickConfig or null`
+
+        `double_click`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `hold_key: optional ComputerHoldKeyConfig or null`
+
+        `hold_key`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `key: optional ComputerKeyConfig or null`
+
+        `key`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `left_click: optional ComputerLeftClickConfig or null`
+
+        `left_click`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `left_click_drag: optional ComputerLeftClickDragConfig or null`
+
+        `left_click_drag`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `left_mouse_down: optional ComputerLeftMouseDownConfig or null`
+
+        `left_mouse_down`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `left_mouse_up: optional ComputerLeftMouseUpConfig or null`
+
+        `left_mouse_up`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `middle_click: optional ComputerMiddleClickConfig or null`
+
+        `middle_click`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `mouse_move: optional ComputerMouseMoveConfig or null`
+
+        `mouse_move`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `right_click: optional ComputerRightClickConfig or null`
+
+        `right_click`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `screenshot: optional ComputerScreenshotConfig or null`
+
+        `screenshot`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `scroll: optional ComputerScrollConfig or null`
+
+        `scroll`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `triple_click: optional ComputerTripleClickConfig or null`
+
+        `triple_click`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `type: optional ComputerTypeConfig or null`
+
+        `type`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `wait: optional ComputerWaitConfig or null`
+
+        `wait`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
+      - `zoom: optional ComputerZoomConfig or null`
+
+        `zoom`'s config overrides.
+
+        - `defer_loading: optional boolean or null`
+
+          Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
+
+        - `enabled: optional boolean or null`
+
+          Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
+
   - `ToolTextEditor20250124 object { name, type, allowed_callers, 4 more }`
 
     - `name: "str_replace_editor"`

     - `expires_at: string`
 
       The time at which the container will expire.
+
+    - `skills: array of ContainerSkill or null`
+
+      Skills loaded in the container
+
+      - `skill_id: string`
+
+        Skill ID
+
+      - `type: "anthropic" or "custom"`
+
+        Type of skill - either 'anthropic' (built-in) or 'custom' (user-defined)
+
+        - `"anthropic"`
+
+        - `"custom"`
+
+      - `version: string`
+
+        Skill version or 'latest' for most recent version
 
   - `content: array of ContentBlock`
 

 
         - `"redacted_thinking"`
 
-    - `ToolUseBlock object { id, caller, input, 2 more }`
+    - `ToolUseBlock object { id, caller, input, 3 more }`
 
       - `id: string`
 

       - `type: "tool_use"`
 
         - `"tool_use"`
+
+      - `toolset_name: optional string or null`
+
+        For a toolset member tool_use, the toolset family.
 
     - `ServerToolUseBlock object { id, caller, input, 2 more }`
 

               "role": "user"
             }
           ],
-          "model": "claude-opus-4-6",
+          "model": "claude-opus-5",
           "stream": false,
           "system": [
             {

   "id": "msg_013Zva2CMHLNnXjNJJKqJ2EF",
   "container": {
     "id": "container_011CpZohnwH4vuy7gazohgSP",
-    "expires_at": "2019-12-27T18:11:19.117Z"
+    "expires_at": "2019-12-27T18:11:19.117Z",
+    "skills": [
+      {
+        "skill_id": "pdf",
+        "type": "anthropic",
+        "version": "latest"
+      }
+    ]
   },
   "content": [
     {

       "type": "text"
     }
   ],
-  "model": "claude-opus-4-6",
+  "model": "claude-opus-5",
   "role": "assistant",
   "stop_details": {
     "category": "cyber",