> ## Documentation Index > Fetch the complete documentation index at: https://docs.55-tech.com/llms.txt > Use this file to discover all available pages before exploring further. # Fetch with JavaScript rendering > Fetch a URL with full JavaScript rendering. Works just like /fetch — all parameters via headers. Use this instead of /fetch when the target requires JavaScript to load content. If X-Expect-Selector or X-Expect-Contains is set and the page doesn't match, the API retries on a different node. ## OpenAPI ````yaml /zh/scraping-api/openapi.json get /browser openapi: 3.1.0 info: title: 55 Tech Scraping API description: >- Distributed fetch network. Route HTTP, browser, WebSocket, and AMQP requests through 80+ geo-distributed agents with health-aware routing and block detection. version: 2.2.0 contact: name: 55 Tech Support email: contact@55-tech.com servers: - url: https://scraping-api.55-tech.com description: Production security: - ApiKeyHeader: [] tags: - name: Fetch description: Proxy HTTP requests through the agent network. - name: Browser description: Fetch with full JavaScript rendering, cookies, and screenshots. - name: Network description: Agent registry, network status, and domain health. - name: AMQP description: AMQP/RabbitMQ consumer relay via SSE. - name: Usage description: Per-key usage metrics. - name: Debug description: Debug and diagnostic endpoints. - name: System description: Health checks and system endpoints. paths: /browser: get: tags: - Browser summary: Fetch with JavaScript rendering description: >- Fetch a URL with full JavaScript rendering. Works just like /fetch — all parameters via headers. Use this instead of /fetch when the target requires JavaScript to load content. If X-Expect-Selector or X-Expect-Contains is set and the page doesn't match, the API retries on a different node. operationId: browser_fetch parameters: - $ref: '#/components/parameters/XTargetURL' - name: X-Wait-Strategy in: header description: >- When the page is ready: load (DOMContentLoaded), networkidle (no pending requests), or selector (wait for CSS selector). schema: type: string enum: - load - networkidle - selector default: load - name: X-Wait-Selector in: header description: 'CSS selector to wait for (only with X-Wait-Strategy: selector).' schema: type: string - name: X-Screenshot in: header description: Capture a full-page PNG screenshot. Set to 1 or true. schema: type: string - name: X-JS-Expression in: header description: >- JavaScript to evaluate after the page is ready. Result returned in js_result. schema: type: string - name: X-Expect-Selector in: header description: >- CSS selector that must exist in the rendered page. Retries on a different node if missing. schema: type: string - name: X-Expect-Contains in: header description: >- Substring that must exist in the page body. Retries on a different node if missing. schema: type: string - name: X-Steps in: header description: >- JSON array of sequential browser actions (navigate, click, type, wait, evaluate, screenshot, sleep, etc.). Executes after page load, before capture. schema: type: string - name: X-Proxy in: header description: Route through a proxy (http:// or socks5://). schema: type: string - name: X-Block-Resources in: header description: >- Comma-separated resource types to block: image, font, stylesheet, media. No default for /browser. schema: type: string - name: Cookie in: header description: >- Cookies to inject before navigation (standard format: name=value; name2=value2). schema: type: string - name: X-Cookies in: header description: >- Cookies as JSON array for full control: [{"name":"s","value":"v","domain":".example.com"}]. schema: type: string - $ref: '#/components/parameters/XGeo' - $ref: '#/components/parameters/XAgent' - $ref: '#/components/parameters/XTimeout' responses: '200': description: Rendered page with metadata, cookies, and optional screenshot. content: application/json: schema: $ref: '#/components/schemas/BrowserFetchResponse' example: meta: status: 200 final_url: https://example.com/ http_version: '' elapsed_ms: 3200 blocked: false headers: content-type: text/html; charset=utf-8 agent: id: scraping-de5 bytes: 45210 raw: ... raw_json: null cookies: - name: session_id value: a1b2c3... domain: .example.com path: / secure: true httpOnly: true sameSite: Lax expires: 1735689600 screenshot: null js_result: null '401': description: Missing API key. '403': description: Invalid API key. '429': description: Rate limit exceeded. '502': description: No healthy agent available, or browser/validation error. '504': description: Browser timeout. components: parameters: XTargetURL: name: X-Target-URL in: header description: >- Target URL (no encoding needed). Recommended for URLs with query parameters. schema: type: string XGeo: name: X-Geo in: header description: >- Target countries as comma-separated ISO codes (e.g. US,DE,AT). Aliases: X-Geo-CC, X-CC, X-Country, X-Geo-Strict. schema: type: string XAgent: name: X-Agent in: header description: >- Route through specific agent(s) by slug (e.g. de1) or comma-separated list for random pick (e.g. de1,at5,us3). schema: type: string XTimeout: name: X-Timeout in: header description: 'Override request timeout in seconds (default: 30).' schema: type: string schemas: BrowserFetchResponse: type: object properties: meta: $ref: '#/components/schemas/MetaInfo' raw: type: string nullable: true description: Rendered page body as text (when not JSON). raw_json: nullable: true description: Parsed JSON body (when response is valid JSON, otherwise null). cookies: type: array items: $ref: '#/components/schemas/BrowserCookie' description: All cookies captured during rendering, including httpOnly cookies. screenshot: type: string nullable: true description: Base64-encoded full-page PNG screenshot (null if not requested). js_result: nullable: true description: Return value of jsExpression evaluation (null if not provided). MetaInfo: type: object properties: status: type: integer description: HTTP status code from the origin. final_url: type: string description: Final URL after any redirects. http_version: type: string description: HTTP version used (e.g. HTTP/2). elapsed_ms: type: integer description: Round-trip time in milliseconds. blocked: type: boolean description: true if bot detection patterns were found in the response. headers: type: object additionalProperties: type: string description: Response headers from the origin. agent: type: object properties: id: type: string description: Node ID that served the request, e.g. scraping-de1. bytes: type: integer description: Response body size in bytes. BrowserCookie: type: object properties: name: type: string description: Cookie name. value: type: string description: Cookie value. domain: type: string description: Cookie domain (e.g. .example.com). path: type: string default: / description: Cookie path. secure: type: boolean default: false description: Secure flag. httpOnly: type: boolean default: false description: HttpOnly flag. sameSite: type: string default: Lax description: SameSite attribute (Strict, Lax, None). expires: type: number default: 0 description: Expiry as Unix epoch. 0 = session cookie. securitySchemes: ApiKeyHeader: type: apiKey in: header name: X-API-Key description: API key passed in the X-API-Key header. ````