> ## 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. # Create a browser (Beta) > Beta: create a browser sandbox, which runs one persistent Chrome that other sandboxes attach to. Logins made in it persist across restarts. It keeps its memory when it stops and is never deleted automatically. ## OpenAPI ````yaml /langsmith/langsmith-platform-openapi.json post /api/v2/sandboxes/browsers 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: post: tags: - sandboxes summary: Create a browser (Beta) description: >- Beta: create a browser sandbox, which runs one persistent Chrome that other sandboxes attach to. Logins made in it persist across restarts. It keeps its memory when it stops and is never deleted automatically. parameters: [] requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/sandboxes.CreateBrowserPayload' responses: '201': description: Created content: application/json: schema: $ref: '#/components/schemas/sandboxes.BrowserResponse' '409': description: Name already exists content: application/json: schema: $ref: '#/components/schemas/sandboxes.ErrorResponse' '422': description: Validation error content: application/json: schema: $ref: '#/components/schemas/sandboxes.ErrorResponse' '429': description: Quota exceeded 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.CreateBrowserPayload: type: object properties: hidpi: description: >- HiDPI renders pages at twice the resolution, so the live view is sharp on HiDPI screens, at four times the pixels for the browser to render and stream. Off by default, and fixed once the browser is created. type: boolean idle_ttl_seconds: description: >- IdleTTLSeconds stops the browser after this long without use. A stopped browser resumes with its memory on the next connection. Defaults to the sandbox default; 0 disables the idle stop. type: integer minimum: 0 mem_bytes: type: integer name: description: |- Name of the browser sandbox. Generated when omitted, as "browser-" followed by the browser's ID. type: string vcpus: description: >- VCPUs and MemBytes size the browser sandbox, as for any sandbox. With neither set, a browser gets 2 vCPUs and 8 GiB. type: integer sandboxes.BrowserResponse: type: object properties: attachments: description: Attachments are listed only while the browser is running. type: array items: $ref: '#/components/schemas/sandboxes.BrowserAttachment' hidpi: description: |- HiDPI reports whether pages render at twice the resolution. It is reported only while the browser is running. type: boolean id: type: string name: type: string status: type: string sandboxes.ErrorResponse: type: object properties: detail: type: object properties: error: type: string error_id: type: string message: type: string 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.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 ````