> ## Documentation Index > Fetch the complete documentation index at: https://docs.langchain.com/llms.txt > Use this file to discover all available pages before exploring further. # Attach a sandbox to a browser (Beta) > Beta: give a sandbox its own window of the browser, or, with no sandbox, open a window for the person calling (or, with controller "agent", for a client to drive over api_cdp_url). The response's cdp_url is the Chrome DevTools endpoint the sandbox connects to, and api_cdp_url the same endpoint through the API; a client can open more tabs, which stay in its window. Windows share the browser's cookies and logins. Keeping each sandbox to its own window is best effort, not a security boundary: attach only sandboxes you would trust with every login in the browser. With share_localhost, the browser can also reach the servers the sandbox runs, at the response's localhost_alias. Attaching takes, for the browser and for the attached sandbox each, being its creator or a role with sandboxes:exec. With unrestricted, nothing is filtered: the window's CDP clients (its sandbox, or anyone using its api_cdp_url) get the whole browser, including people's windows, every site's cookies, and commands that close it. It needs nothing beyond what any attach needs. ## OpenAPI ````yaml /langsmith/langsmith-platform-openapi.json post /api/v2/sandboxes/browsers/{name}/attachments openapi: 3.1.0 info: title: LangSmith description: >+ The LangSmith API is used to programmatically create and manage LangSmith resources. ## Host https://api.smith.langchain.com ## Authentication To authenticate with the LangSmith API, set the `X-Api-Key` header to a valid [LangSmith API key](https://docs.langchain.com/langsmith/create-account-api-key#create-an-api-key). version: 0.1.0 servers: - url: / security: [] tags: - name: run x-group: Tracing - name: runs x-group: Tracing - name: sessions x-group: Tracing - name: tracer-sessions x-group: Tracing - name: threads x-group: Threads - name: datasets x-group: Datasets - name: examples x-group: Datasets - name: evaluators x-group: Evaluation - name: experiment-view-overrides x-group: Evaluation - name: experiments x-group: Evaluation - name: annotation-queues x-group: Feedback & Annotation - name: annotation_queues x-group: Feedback & Annotation - name: feedback x-group: Feedback & Annotation - name: feedback-configs x-group: Feedback & Annotation - name: alert_rules x-group: Monitoring - name: bulk-exports x-group: Monitoring - name: charts x-group: Monitoring - name: commits x-group: Prompts & Playground - name: directories x-group: Prompts & Playground - name: hub_environments x-group: Prompts & Playground - name: playground-settings x-group: Prompts & Playground - name: prompt-webhooks x-group: Prompts & Playground - name: prompts x-group: Prompts & Playground - name: tag-transitions x-group: Prompts & Playground - name: comments x-group: Prompt Hub - name: likes x-group: Prompt Hub - name: optimization-jobs x-group: Prompt Hub - name: ownerships x-group: Prompt Hub - name: repos x-group: Prompt Hub - name: settings x-group: Prompt Hub - name: tags x-group: Prompt Hub - name: integrations x-group: Integrations & Tools - name: mcp x-group: Integrations & Tools - name: mcp_vendors x-group: Integrations & Tools - name: oauth x-group: Integrations & Tools - name: tools x-group: Integrations & Tools - name: gateway-policies x-group: LLM Gateway - name: sandboxes x-group: Sandboxes - name: issues x-group: Issues - name: issues-agent x-group: Issues - name: Organizations x-group: Administration - name: SCIM Tokens x-group: Administration - name: TTL Settings x-group: Administration - name: access_policies x-group: Administration - name: api-key x-group: Administration - name: audit-logs x-group: Administration - name: auth x-group: Administration - name: aws_marketplace x-group: Administration - name: data_planes x-group: Administration - name: me x-group: Administration - name: orgs x-group: Administration - name: service-accounts x-group: Administration - name: tenant x-group: Administration - name: ttl-settings x-group: Administration - name: usage-limits x-group: Administration - name: workspaces x-group: Administration - name: ace x-group: System - name: backfills x-group: System - name: features x-group: System - name: info x-group: System - name: model-price-map x-group: System - name: public x-group: System - name: fleet orgs - name: fleet secrets - name: fleet tenants - name: fleet threads x-hidden: true - name: fleet users - name: productfeedback x-hidden: true - name: usage paths: /api/v2/sandboxes/browsers/{name}/attachments: post: tags: - sandboxes summary: Attach a sandbox to a browser (Beta) description: >- Beta: give a sandbox its own window of the browser, or, with no sandbox, open a window for the person calling (or, with controller "agent", for a client to drive over api_cdp_url). The response's cdp_url is the Chrome DevTools endpoint the sandbox connects to, and api_cdp_url the same endpoint through the API; a client can open more tabs, which stay in its window. Windows share the browser's cookies and logins. Keeping each sandbox to its own window is best effort, not a security boundary: attach only sandboxes you would trust with every login in the browser. With share_localhost, the browser can also reach the servers the sandbox runs, at the response's localhost_alias. Attaching takes, for the browser and for the attached sandbox each, being its creator or a role with sandboxes:exec. With unrestricted, nothing is filtered: the window's CDP clients (its sandbox, or anyone using its api_cdp_url) get the whole browser, including people's windows, every site's cookies, and commands that close it. It needs nothing beyond what any attach needs. parameters: - description: Browser name or ID name: name in: path required: true schema: type: string requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/sandboxes.AttachBrowserPayload' responses: '201': description: Created content: application/json: schema: $ref: '#/components/schemas/sandboxes.BrowserAttachment' '400': description: Size out of range, or controller is not agent or user content: application/json: schema: $ref: '#/components/schemas/sandboxes.ErrorResponse' '404': description: Browser or sandbox not found content: application/json: schema: $ref: '#/components/schemas/sandboxes.ErrorResponse' '501': description: The browser beta is not enabled content: application/json: schema: $ref: '#/components/schemas/sandboxes.ErrorResponse' security: - API Key: [] - Tenant ID: [] - Bearer Auth: [] components: schemas: sandboxes.AttachBrowserPayload: type: object properties: controller: description: >- Controller is who drives a window opened with no sandbox: "user" (default) for a person in the live view, or "agent" for a client that drives it over api_cdp_url. A sandbox's window always starts with "agent". type: string enum: - agent - user height: type: integer maximum: 2400 minimum: 300 name: description: >- Name labels the window in the live view; defaults to the sandbox name. type: string sandbox: description: >- Sandbox is the name or ID of the sandbox to attach. Leave it out to open a window for the person calling, to use from the live view. type: string share_localhost: description: >- ShareLocalhost shares the sandbox's localhost with the browser, so pages can open the servers it runs, such as dev servers, at the response's localhost_alias. It reaches every port of the sandbox, including servers bound only to its localhost. Off by default. Not available for a window opened with no sandbox, or when the sandbox is itself a browser. type: boolean unrestricted: description: >- Unrestricted gives the window's CDP clients (its sandbox, or anyone using its api_cdp_url) the whole browser, with nothing filtered: every window and tab including people's, every site's cookies, and commands that close or crash the browser. Taking over its window does not pause them. type: boolean width: description: |- Width and Height size the window's page in CSS pixels; set both or neither. Without them the window opens at 1280x800. type: integer maximum: 3840 minimum: 400 sandboxes.BrowserAttachment: type: object properties: act_url: type: string api_cdp_url: description: >- APICDPURL is the same Chrome DevTools endpoint through the LangSmith API, for clients outside any sandbox. It takes any API credential: headers as for any API call (X-Api-Key, or Authorization: Bearer with an OAuth access token, plus X-Tenant-Id where needed), or, for clients that take only a URL, api_key, token and tenant_id query parameters. type: string cdp_url: description: >- CDPURL is the Chrome DevTools endpoint the attached sandbox connects to, for example with Playwright's connect_over_cdp. It works only from inside that sandbox. type: string clients: description: >- Clients are the sandboxes currently connected to this window, with "api" for each client connected through api_cdp_url. An unrestricted window's connections are not listed. type: array items: type: string controller: description: >- Controller is "agent" while the attached sandbox drives the window and "user" while a person has taken it over. type: string enum: - agent - user created_at: type: string height: type: integer id: type: string links_expire_at: type: string format: date-time localhost_alias: description: >- LocalhostAlias is the sandbox's localhost as the browser sees it: open http://: in a window to reach a server listening on that port in the sandbox, whether bound to localhost or to all interfaces (any port but 80 and 443). While this is the only sandbox sharing its localhost, http://localhost: works too. Pages on other sites can navigate to a plain-HTTP server there but cannot fetch from it. Set only for windows attached with share_localhost. type: string name: type: string reason: description: Reason is why the agent asked a person to take over, when it did. type: string sandbox: description: Sandbox is the attached sandbox; empty for a window a person opened. type: string tabs: type: array items: $ref: '#/components/schemas/sandboxes.BrowserTab' unrestricted: description: >- Unrestricted windows give their sandbox the whole browser over CDP, with nothing filtered: every window and tab, every site's cookies, and commands that close or crash the browser. Taking over such a window does not pause its sandbox, and the LSBrowserControl domain is not available. type: boolean view_url: description: >- ViewURL and ActURL open the window on the sandbox service domain with no LangSmith login, for an agent to send to a person: ViewURL to watch it, ActURL also to use it while its controller is "user". Anyone holding a link can open the window until LinksExpireAt. Each response mints new ones; they are returned only to those who may use the browser. type: string width: description: >- Width and Height are the window's page size in CSS pixels, when it was given one; a window without one keeps Chrome's default of 1280x800. type: integer sandboxes.ErrorResponse: type: object properties: detail: type: object properties: error: type: string error_id: type: string message: type: string sandboxes.BrowserTab: type: object properties: id: type: string title: type: string url: type: string securitySchemes: API Key: type: apiKey in: header name: X-API-Key Tenant ID: type: apiKey in: header name: X-Tenant-Id Bearer Auth: type: http description: >- Bearer tokens are used to authenticate from the UI. Must also specify x-tenant-id or x-organization-id (for org scoped apis). scheme: bearer ````