FastAF Scholar API

openapi: 3.2.0
info:
  title: FastAF Scholar API
  version: v1
  contact:
    email: support@fastaf.co
    url: https://fastaf.co/docs/#x402
  description: 'FastAF is a web data API for AI agents: Google SERP, Maps, ecommerce, web scraping, AI extraction, screenshots, news, jobs, research, public profiles and video transcripts. Use prepaid API keys or account-free x402 v2 payments.'
  x-guidance: 'Use GET /x402/v1/{endpoint} with query parameters (not POST or a JSON body). Choose serp for Google search, maps for places, news/shopping/scholar/jobs for specialized search, ai for Google AI Mode, amazon/youtube for their resource variants, linkedin/x for public profiles, walmart/zillow/ebay for structured commerce or listings, scrape for public HTML or markdown, and screenshot for images. Use the dedicated zillow and ebay endpoints instead of scrape for those sites. The q and lang aliases are accepted for query (search_query on YouTube) and language. Send a valid unpaid request first; read the x402 v2 PAYMENT-REQUIRED header, sign with an x402 client such as @x402/fetch, and retry the identical URL with PAYMENT-SIGNATURE. USDC payment uses the network and amount in that live challenge; no API-key authentication is needed. Only successful results are settled; inspect PAYMENT-RESPONSE for the receipt. Prices here are decimal USD, while the challenge uses USDC atomic units (six decimals). Dynamic prices depend on advance_search (serp), resource (amazon/youtube), or rendering, proxies/country and AI extraction (scrape). Scrape site defaults, including Booking rendering and Reddit feed mode, are applied before quoting. A bare unsigned URL returns a default-variant discovery quote only: add valid parameters and request a new challenge before paying. Unpaid HEAD probes also return PAYMENT-REQUIRED with no body; use GET, not HEAD, to pay for data. Invalid parameterized requests and blocked targets return 400; payment headers never bypass validation. Never reuse a settled signature for a new call. Respect Retry-After on rate/capacity errors. For the separate prepaid-key API and authenticated credit-pack top-up, see /v1/openapi.json. Get a free API key at https://fastaf.co/signup/ with an email address, terms acceptance and browser verification. No card is required. POST /public/signup sends an email confirmation link and sets a dashboard session cookie; it does not return an API key. Follow the emailed GET /public/signin/{token} link, then create a key in the dashboard (POST /v1/keys with the session cookie). The key is shown only once. Email confirmation unlocks 2 free calls per account in total, not per day, shared across all keys and all offered REST/MCP endpoints, valid for 12 months; failed calls restore their slot. Unverified trial accounts receive email_verification_required (403) before any data call or trial reservation. Signups are limited per IPv4 /24 or IPv6 /64 network per UTC day (default 3); 429 means retry after the reset. GET /v1/usage reports free_requests_remaining separately from balance_credits. POST /v1/signup is retired and always returns 410 signup_disabled. Agents without an inbox can use /x402/v1/{endpoint} without an account.'
  x-signup-guidance: Get a free API key at https://fastaf.co/signup/ with an email address, terms acceptance and browser verification. No card is required. POST /public/signup sends an email confirmation link and sets a dashboard session cookie; it does not return an API key. Follow the emailed GET /public/signin/{token} link, then create a key in the dashboard (POST /v1/keys with the session cookie). The key is shown only once. Email confirmation unlocks 2 free calls per account in total, not per day, shared across all keys and all offered REST/MCP endpoints, valid for 12 months; failed calls restore their slot. Unverified trial accounts receive email_verification_required (403) before any data call or trial reservation. Signups are limited per IPv4 /24 or IPv6 /64 network per UTC day (default 3); 429 means retry after the reset. GET /v1/usage reports free_requests_remaining separately from balance_credits. POST /v1/signup is retired and always returns 410 signup_disabled. Agents without an inbox can use /x402/v1/{endpoint} without an account.
servers:
- url: https://api.fastaf.co
tags:
- name: Scholar
paths:
  /v1/scholar:
    get:
      tags:
      - Scholar
      summary: Scholarly search results
      description: 'Google Scholar results as JSON: title, authors, publication, year, citation count and link.'
      security:
      - bearerAuth: []
      responses:
        '200':
          description: Provider response.
          headers:
            X-FastAF-Credits-Used:
              schema:
                type: integer
            X-FastAF-Cost-Version:
              schema:
                type: string
          content:
            application/json:
              schema:
                type: object
                properties:
                  scholar_results:
                    type: array
                    items:
                      type: object
                      properties:
                        title:
                          type: string
                        displayed_link:
                          type: string
                        snippet:
                          type: string
                        inline_links:
                          type: object
                          properties:
                            cited_by:
                              type: object
                              properties:
                                total:
                                  type: string
                                cites_id:
                                  type: string
                              additionalProperties: true
                          additionalProperties: true
                        title_link:
                          type: string
                      additionalProperties: true
                additionalProperties: true
              example:
                scholar_results:
                - title: Retrieval-Augmented Generation for Knowledge-Intensive NLP Tasks
                  displayed_link: P Lewis et al. - NeurIPS, 2020
                  snippet: A retrieval-augmented model combines a language model with a searchable document index.
                  inline_links:
                    cited_by:
                      total: Cited by 120
                      cites_id: '1234567890123456789'
                  title_link: https://arxiv.org/abs/2005.11401
            text/html:
              schema:
                type: string
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '403':
          $ref: '#/components/responses/Forbidden'
        '429':
          $ref: '#/components/responses/TooManyRequests'
        '502':
          $ref: '#/components/responses/BadGateway'
        '503':
          $ref: '#/components/responses/ServiceUnavailable'
        '504':
          $ref: '#/components/responses/GatewayTimeout'
      x-fastaf-credit-cost: 5
      x-fastaf-cost-version: v1
      operationId: getScholar
      parameters:
      - name: html
        in: query
        required: false
        description: Return raw source HTML instead of parsed JSON when true; true/false, default false. No option surcharge; 5 credits per successful request.
        schema:
          type: boolean
      - name: query
        in: query
        required: false
        description: 'Scholar search text, supporting author: and source:. Required unless cites or cluster is supplied. May refine cites results; cannot combine with cluster. No default. No option surcharge; 5 credits per successful request.'
        schema:
          type: string
          maxLength: 8192
      - name: language
        in: query
        required: false
        description: Result/interface language code, e.g. en, es, fr or de; default en. Use lr, where supported, to restrict document languages. No option surcharge; 5 credits per successful request.
        schema:
          type: string
          maxLength: 8192
      - name: lr
        in: query
        required: false
        description: 'Document-language filter: lang_en or a pipe-separated list such as lang_en|lang_fr. Omitted: no explicit language restriction. No option surcharge; 5 credits per successful request.'
        schema:
          type: string
          maxLength: 8192
      - name: cites
        in: query
        required: false
        description: Scholar article ID for a Cited by lookup, copied from a Scholar result. May combine with query to filter citing papers, but not cluster. No default. No option surcharge; 5 credits per successful request.
        schema:
          type: string
          maxLength: 8192
      - name: as_ylo
        in: query
        required: false
        description: Inclusive earliest publication year as a four-digit string, e.g. 2020. Omit for no lower year bound; may combine with as_yhi. No option surcharge; 5 credits per successful request.
        schema:
          type: string
          maxLength: 8192
      - name: as_yhi
        in: query
        required: false
        description: Inclusive latest publication year as a four-digit string, e.g. 2026. Omit for no upper year bound; may combine with as_ylo. No option surcharge; 5 credits per successful request.
        schema:
          type: string
          maxLength: 8192
      - name: scisbd
        in: query
        required: false
        description: 'Scholar result mode: string 1 requests abstract results, 0 all results. Omitted: source-default result mode. No option surcharge; 5 credits per successful request.'
        schema:
          type: string
          maxLength: 8192
      - name: cluster
        in: query
        required: false
        description: Scholar article cluster ID for an All versions lookup. Use instead of query/cites, never together; no default. No option surcharge; 5 credits per successful request.
        schema:
          type: string
          maxLength: 8192
      - name: as_sdt
        in: query
        required: false
        description: 'Scholar search/filter codes: 0 excludes patents (default), 7 includes patents, 4 selects US case law. Court codes can follow 4, e.g. 4,33,192. No option surcharge; 5 credits per successful request.'
        schema:
          type: string
          maxLength: 8192
      - name: safe
        in: query
        required: false
        description: 'Adult-content filter: active enables SafeSearch; off disables it (default off). No option surcharge; 5 credits per successful request.'
        schema:
          type: string
          maxLength: 8192
      - name: filter
        in: query
        required: false
        description: 'Duplicate/omitted-result filtering: string 1 enables it (default); 0 includes similar and normally omitted results. No option surcharge; 5 credits per successful request.'
        schema:
          type: string
          maxLength: 8192
      - name: as_vis
        in: query
        required: false
        description: 'Citation-only results: string 1 excludes them, 0 includes them (default 0). No option surcharge; 5 credits per successful request.'
        schema:
          type: string
          maxLength: 8192
      - name: as_rr
        in: query
        required: false
        description: 'Review-paper filter: string 1 returns review articles only, 0 all article types (default 0). No option surcharge; 5 credits per successful request.'
        schema:
          type: string
          maxLength: 8192
      - name: page
        in: query
        required: false
        description: 'Zero-based results page: 0 is the first page, 1 the second; non-negative integer, default 0. Each page is a separate request. No option surcharge; 5 credits per successful request.'
        schema:
          type: integer
          minimum: 0
      - name: results
        in: query
        required: false
        description: 'Requested results per Scholar page, integer at least 1; omitted: source-default page size. Google may return fewer; not a count of separately billed requests. No option surcharge; 5 credits per successful request.'
        schema:
          type: integer
          minimum: 1
    post:
      tags:
      - Scholar
      summary: Scholarly search results
      description: 'Google Scholar results as JSON: title, authors, publication, year, citation count and link.'
      security:
      - bearerAuth: []
      responses:
        '200':
          description: Provider response.
          headers:
            X-FastAF-Credits-Used:
              schema:
                type: integer
            X-FastAF-Cost-Version:
              schema:
                type: string
          content:
            application/json:
              schema:
                type: object
                properties:
                  scholar_results:
                    type: array
                    items:
                      type: object
                      properties:
                        title:
                          type: string
                        displayed_link:
                          type: string
                        snippet:
                          type: string
                        inline_links:
                          type: object
                          properties:
                            cited_by:
                              type: object
                              properties:
                                total:
                                  type: string
                                cites_id:
                                  type: string
                              additionalProperties: true
                          additionalProperties: true
                        title_link:
                          type: string
                      additionalProperties: true
                additionalProperties: true
              example:
                scholar_results:
                - title: Retrieval-Augmented Generation for Knowledge-Intensive NLP Tasks
                  displayed_link: P Lewis et al. - NeurIPS, 2020
                  snippet: A retrieval-augmented model combines a language model with a searchable document index.
                  inline_links:
                    cited_by:
                      total: Cited by 120
                      cites_id: '1234567890123456789'
                  title_link: https://arxiv.org/abs/2005.11401
            text/html:
              schema:
                type: string
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '403':
          $ref: '#/components/responses/Forbidden'
        '429':
          $ref: '#/components/responses/TooManyRequests'
        '502':
          $ref: '#/components/responses/BadGateway'
        '503':
          $ref: '#/components/responses/ServiceUnavailable'
        '504':
          $ref: '#/components/responses/GatewayTimeout'
      x-fastaf-credit-cost: 5
      x-fastaf-cost-version: v1
      operationId: postScholar
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              additionalProperties: false
              properties:
                html:
                  type: boolean
                  description: Return raw source HTML instead of parsed JSON when true; true/false, default false. No option surcharge; 5 credits per successful request.
                query:
                  type: string
                  maxLength: 8192
                  description: 'Scholar search text, supporting author: and source:. Required unless cites or cluster is supplied. May refine cites results; cannot combine with cluster. No default. No option surcharge; 5 credits per successful request.'
                language:
                  type: string
                  maxLength: 8192
                  description: Result/interface language code, e.g. en, es, fr or de; default en. Use lr, where supported, to restrict document languages. No option surcharge; 5 credits per successful request.
                lr:
                  type: string
                  maxLength: 8192
                  description: 'Document-language filter: lang_en or a pipe-separated list such as lang_en|lang_fr. Omitted: no explicit language restriction. No option surcharge; 5 credits per successful request.'
                cites:
                  type: string
                  maxLength: 8192
                  description: Scholar article ID for a Cited by lookup, copied from a Scholar result. May combine with query to filter citing papers, but not cluster. No default. No option surcharge; 5 credits per successful request.
                as_ylo:
                  type: string
                  maxLength: 8192
                  description: Inclusive earliest publication year as a four-digit string, e.g. 2020. Omit for no lower year bound; may combine with as_yhi. No option surcharge; 5 credits per successful request.
                as_yhi:
                  type: string
                  maxLength: 8192
                  description: Inclusive latest publication year as a four-digit string, e.g. 2026. Omit for no upper year bound; may combine with as_ylo. No option surcharge; 5 credits per successful request.
                scisbd:
                  type: string
                  maxLength: 8192
                  description: 'Scholar result mode: string 1 requests abstract results, 0 all results. Omitted: source-default result mode. No option surcharge; 5 credits per successful request.'
                cluster:
                  type: string
                  maxLength: 8192
                  description: Scholar article cluster ID for an All versions lookup. Use instead of query/cites, never together; no default. No option surcharge; 5 credits per successful request.
                as_sdt:
                  type: string
                  maxLength: 8192
                  description: 'Scholar search/filter codes: 0 excludes patents (default), 7 includes patents, 4 selects US case law. Court codes can follow 4, e.g. 4,33,192. No option surcharge; 5 credits per successful request.'
                safe:
                  type: string
                  maxLength: 8192
                  description: 'Adult-content filter: active enables SafeSearch; off disables it (default off). No option surcharge; 5 credits per successful request.'
                filter:
                  type: string
                  maxLength: 8192
                  description: 'Duplicate/omitted-result filtering: string 1 enables it (default); 0 includes similar and normally omitted results. No option surcharge; 5 credits per successful request.'
                as_vis:
                  type: string
                  maxLength: 8192
                  description: 'Citation-only results: string 1 excludes them, 0 includes them (default 0). No option surcharge; 5 credits per successful request.'
                as_rr:
                  type: string
                  maxLength: 8192
                  description: 'Review-paper filter: string 1 returns review articles only, 0 all article types (default 0). No option surcharge; 5 credits per successful request.'
                page:
                  type: integer
                  minimum: 0
                  description: 'Zero-based results page: 0 is the first page, 1 the second; non-negative integer, default 0. Each page is a separate request. No option surcharge; 5 credits per successful request.'
                results:
                  type: integer
                  minimum: 1
                  description: 'Requested results per Scholar page, integer at least 1; omitted: source-default page size. Google may return fewer; not a count of separately billed requests. No option surcharge; 5 credits per successful request.'
              anyOf:
              - required:
                - query
              - required:
                - cites
              - required:
                - cluster
components:
  responses:
    BadGateway:
      description: The upstream request failed.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    PaymentRequired:
      description: The account has insufficient credits.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    TooManyRequests:
      description: A rate or concurrency limit was reached.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    BadRequest:
      description: Invalid request or parameters.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    Forbidden:
      description: The account is suspended or email verification is required before data calls.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    Unauthorized:
      description: A valid bearer API key is required.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    ServiceUnavailable:
      description: The service is temporarily unavailable.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    GatewayTimeout:
      description: The upstream request timed out.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
  schemas:
    Error:
      type: object
      required:
      - error
      properties:
        error:
          type: object
          required:
          - code
          - message
          properties:
            code:
              type: string
            message:
              type: string
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: API key
    sessionCookie:
      type: apiKey
      in: cookie
      name: fastaf_session