> ## Documentation Index > Fetch the complete documentation index at: https://docs.zenrows.com/llms.txt > Use this file to discover all available pages before exploring further. > ## Agent Instructions > The Zenrows API (Fetch, Extract, Crawl and Batch) is described in OpenAPI 3.1 at https://www.zenrows.com/openapi.json and listed in the RFC 9727 API catalog at https://www.zenrows.com/.well-known/api-catalog. Every endpoint also has its own page under /api-reference with its schema. Use the spec for exact parameter names and types. To call Zenrows from an agent, connect the MCP server at https://mcp.zenrows.com/mcp. To search these docs from an agent, connect the docs MCP server at https://docs.zenrows.com/mcp. Agent skills for Zenrows are published at https://github.com/ZenRows/cli and install with `npx skills add ZenRows/cli`. # Get an API key for your agent, no signup required > Start using Zenrows from your agent without signing up. This call returns a working API key straight away: no account setup, no login, no payment details. The key works right away on the free plan. The account is on the Free plan from signup: 5,000 credits per month, renewed monthly. A person who wants to own it opens `claimUrl` and claims it; the same key keeps working. Contract published at https://app.zenrows.com/agent-onboarding/auth.md, and advertised as `agent_auth.signup_endpoint` in https://app.zenrows.com/.well-known/oauth-protected-resource. ## OpenAPI ````yaml /api-reference/openapi.json post /api/agent/signup openapi: 3.1.0 info: title: Zenrows API version: 1.0.0 summary: >- Reach any page, including the protected web, and return it as HTML, Markdown, plaintext, PDF or structured JSON. description: >- Zenrows is web data infrastructure for agents and applications. Three HTTP surfaces are described here: - **Fetch and Extract**: one synchronous request per page, at `https://api.zenrows.com/v1/`. Authentication is the `apikey` query parameter. - **Crawl**: collect the URLs behind one start page, at `https://api.zenrows.com/v1/crawls`. Authentication is the `X-API-Key` header or the `apikey` query parameter. - **Batch**: asynchronous jobs of up to 100,000 URLs, at `https://async.api.zenrows.com/v1`. Authentication is the `X-API-Key` header. **Browser** is not described here because it is not HTTP: you connect Puppeteer or Playwright to a WebSocket endpoint. See https://docs.zenrows.com/browser-sessions/introduction. **Cost.** A request costs 1 credit, 5 with JavaScript rendering, 10 with premium proxies, 25 with both, and 1 to 25 under `mode=auto`. Failed requests are never charged. The free tier is 5,000 credits a month, no card. **Versioning and deprecation.** The version is in the URL path (`/v1`, the only version so far). Inside a version Zenrows only adds: new endpoints, optional parameters, response fields and headers. Nothing is removed or changed. Retiring a version is announced at least twelve months ahead, and every response from a deprecated version carries the `Deprecation` (RFC 9745) and `Sunset` (RFC 8594) headers. Policy: https://docs.zenrows.com/api-versioning. **Getting a key without a human.** `POST https://app.zenrows.com/api/agent/signup` returns a usable key; the spec is at https://www.zenrows.com/auth.md and a setup playbook at https://www.zenrows.com/SKILL.md. termsOfService: https://www.zenrows.com/legal/terms-of-use contact: name: Zenrows support email: support@zenrows.com url: https://www.zenrows.com/contact license: name: Proprietary url: https://www.zenrows.com/legal/terms-of-use servers: - url: https://api.zenrows.com/v1 description: Fetch and Extract (synchronous) security: - apiKeyQuery: [] tags: - name: Fetch description: Retrieve one page, optionally rendered, proxied, converted or extracted. - name: Extract description: Which domains Extract serves, and getting a new one prepared. - name: Crawl description: Collect the URLs behind one start page, and each page's HTML when asked. - name: Batch description: Submit many URLs as one job and collect the results. - name: Account description: Plan, credits and concurrency for the calling key. - name: Onboarding description: Get a working key with no human in the loop. externalDocs: description: Zenrows documentation url: https://docs.zenrows.com paths: /api/agent/signup: post: tags: - Onboarding summary: Get an API key for your agent, no signup required description: >- Start using Zenrows from your agent without signing up. This call returns a working API key straight away: no account setup, no login, no payment details. The key works right away on the free plan. The account is on the Free plan from signup: 5,000 credits per month, renewed monthly. A person who wants to own it opens `claimUrl` and claims it; the same key keeps working. Contract published at https://app.zenrows.com/agent-onboarding/auth.md, and advertised as `agent_auth.signup_endpoint` in https://app.zenrows.com/.well-known/oauth-protected-resource. operationId: createAgentAccount parameters: - name: X-ZR-Agent-Id in: header required: false description: Optional provenance, anonymous and free of personal data. schema: type: string - name: X-ZR-Client in: header required: false description: Optional name of the calling client. schema: type: string - name: X-ZR-Source in: header required: false description: Optional origin of the signup. schema: type: string requestBody: required: false content: application/json: schema: type: object description: No fields are required. An empty body is the normal call. additionalProperties: false responses: '201': description: The account exists and the key works immediately. headers: RateLimit-Policy: $ref: '#/components/headers/RateLimitPolicy' RateLimit: $ref: '#/components/headers/RateLimit' content: application/json: schema: type: object required: - apiKey - accountId - claimUrl - trialEndsAt properties: apiKey: type: string description: >- Pass it as the `apikey` query parameter to Fetch, or as `X-API-Key` to Batch. accountId: type: string format: uuid claimUrl: type: string format: uri description: >- Where a person claims the account to own it. Show this link to a human; do not sit on it. trialEndsAt: type: string format: date-time description: >- End of the first monthly period (signup + 1 month). The Free plan renews monthly; this value is not refreshed. example: apiKey: 8d1c2e9f0a7b4c3d5e6f7a8b9c0d1e2f3a4b5c6d accountId: 3f2b8c1e-5a4d-4e7f-9b6a-1c2d3e4f5a6b claimUrl: https://app.zenrows.com/claim/q7Rk2LmX9pTz?utm_source=agent trialEndsAt: '2026-11-15T10:00:00+00:00' '429': description: >- Error `rate_limited`: three signups per client IP per 24 hours. Wait; do not go looking for another signup URL. headers: RateLimit-Policy: $ref: '#/components/headers/RateLimitPolicy' RateLimit: $ref: '#/components/headers/RateLimit' Retry-After: $ref: '#/components/headers/RetryAfter' content: application/json: schema: $ref: '#/components/schemas/SignupError' '500': description: >- Error `signup_failed`. Retry once with backoff, then hand it to a human. content: application/json: schema: $ref: '#/components/schemas/SignupError' '503': description: >- Error `signup_disabled`: the kill switch is on. Retry later, and do not invent another signup URL. content: application/json: schema: $ref: '#/components/schemas/SignupError' security: [] servers: - url: https://app.zenrows.com description: Dashboard host, which serves the agent onboarding surface components: headers: RateLimitPolicy: description: >- The standing rule, as a structured field: `"signup";q=3;w=86400` is three signups per client IP per 24 hours. Admin-editable, so read it rather than assuming three. schema: type: string example: '"signup";q=3;w=86400' RateLimit: description: >- Where this caller stands: `r` is signups left, `t` is seconds until one frees. `t` counts from the oldest signup still inside the window, so it is a real wait, not the window length restated. schema: type: string example: '"signup";r=1;t=52341' RetryAfter: description: >- Seconds to wait before signing up again. Present only when nothing is left. schema: type: integer example: 52341 schemas: SignupError: type: object description: >- The onboarding surface has its own error shape, flatter than the API's envelope. Branch on `error`. properties: error: type: string examples: - rate_limited - signup_disabled - signup_failed - invalid_key message: type: string securitySchemes: apiKeyQuery: type: apiKey in: query name: apikey description: >- Fetch, Extract, Crawl and the account endpoint accept the key as the `apikey` query parameter. Keys are per account and self-serve: create one in the Zenrows dashboard (app.zenrows.com), or, for an agent with no human present, `POST https://app.zenrows.com/api/agent/signup`. ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.