> ## Documentation Index > Fetch the complete documentation index at: https://docs.repdata.com/llms.txt > Use this file to discover all available pages before exploring further. # SEARCH (POST) Same digital fingerprinting, bot and click-farm detection, and duplication scoring as [SEARCH (GET)](/research-defender/endpoints/get-api-v4-respondents-search-publishable_key), with the parameters sent as a JSON body (`Content-Type: application/json`). `sn_ud` and `sy_nr` are required; `rt_cy_ce` (country code) is strongly recommended. See the [SEARCH guide](/research-defender/guides/search/01-overview) for parameter definitions and failure-reason codes. ## OpenAPI ````yaml POST /api/v4/respondents/search/{publishable_key} openapi: 3.0.3 info: title: Research Defender API version: 1.0.0 description: >- Research Defender protects survey data quality through digital fingerprinting, duplication detection, and open-end text analysis. This reference covers the **SEARCH**, **REVIEW**, and **PREDUPE** products. > ACTIVITY and VERIFY are hosted on a separate domain (resdefio.com) and are documented separately. ## Authentication Client-side calls (SEARCH, REVIEW, GETTOKEN) use your **publishable key** in the URL path. Server-side lookups (destination_platforms) use your **private key**. For enhanced protection, use V3 server-to-server tokens (GETTOKEN) or V4 Hashed Validation. ## Environments Production: `https://prod.rtymgt.com` Staging: `https://staging.rtymgt.com` servers: - url: https://prod.rtymgt.com description: Production - url: https://staging.rtymgt.com description: Staging security: [] paths: /api/v4/respondents/search/{publishable_key}: post: summary: SEARCH (POST) operationId: Search_SearchPost parameters: - name: publishable_key in: path required: true description: Your Research Defender publishable key (client-side). schema: type: string example: 9fc32a73-8165-4dd4-ae19-458bed3c8db5 requestBody: required: true content: application/json: schema: type: object required: - sn_ud - sy_nr properties: sn_ud: type: string description: >- Unique identifier for each API call (do not reuse across surveys/respondents). GUID recommended. sy_nr: type: string description: >- Unique identifier for the client survey, consistent for each survey. rt_cy_ce: type: string description: >- Survey country code (ISO 3166-1 alpha-2) so SEARCH can detect country mismatches. Recommended. rt_sr_pd: type: string description: >- Persistent respondent identifier for deduplication. Only use if you have independently verified respondent identity. pm_sr_id: type: string description: >- Supplier ID (name, abbreviation, or numeric) for backend reporting. sy_gp_nr: type: string description: >- Survey group identifier to deduplicate respondents across surveys. set_window: type: string description: >- Lockout period in days for a survey. Returns days_flag=1 if the respondent attempted the survey within fewer days than this window. coordinates: type: string description: >- Set to 1 to include geolocation, time zone, and weather attributes (latitude, longitude, time_zone, weather_code, state_name). wd: type: string description: Set to 1 to include the last transaction date (d_date). mm: type: string description: >- Set to 1 to disable MaxMind termed-failure detection (failure_reason=18). df_details: type: string description: >- Set to 1 to include an additional dataset with respondent information. sip: type: string description: Set to 1 to show the IP address on the API response. vpt: type: string description: Pass 'check' to check VPN status (returns 1/0). usage_type: type: string description: >- Set to 1 to return usage type: consumer, corporate, or hosting. validation: type: string description: >- V4 only: SHA-256 of the request URL signed with your private key (Hashed Validation). destination_platform_id: type: string description: >- PREDUPE: unique identifier for the destination platform/buyer. Retrieve via the destination_platforms endpoint. destination_platform_survey_number: type: string description: >- PREDUPE: the destination platform's internal survey number (for Research Desk, use the ProjectUd). rt_hd_el: type: string description: Hashed email, if any. csedp3: type: string description: Set to 1 to provide a result from the EDP score (EDP3 node). sisp: type: string description: Set to 1 to provide the ISP (Internet Service Provider). dupe_details: type: string description: >- Set to 1 to show the corresponding details for the duplicate (dupes_details). mfr: type: string description: >- Set to 1 to provide every triggered failure reason (multiple_failure_reason), not just one. tbc: type: string description: >- Set to 1 to allow testers to bypass checks. For testing only. responses: '200': description: Respondent fingerprint and survey duplication results. content: application/json: schema: type: object properties: Respondent: type: object properties: threat_potential_score: type: string description: 1 (lowest) to 99 (highest threat). country: type: string country_code: type: string respondent_risk: type: integer respondent_ud: type: string format: uuid description: >- Stable identifier tracking a respondent across sessions. time_zone: type: string Surveys: type: array items: type: object properties: flag: type: integer description: >- Deprecated. 1 if previously accessed. Use duplicate_score. duplicate_initial_ud: type: string description: >- sn_ud of the most recent prior session for a duplicate. duplicate_potential: type: string description: Deprecated. Use duplicate_score. duplicate_score: type: string description: 100 if duplicate, 0 if unique. country_mismatch: type: integer description: 1 if the geolocated country differs from rt_cy_ce. failure_reason: type: string description: >- Populated when threat_potential_score >= 31. See the SEARCH guide for codes. days_flag: type: integer description: Populated when set_window is used. days_difference: type: integer example: Respondent: threat_potential_score: '23' country: United States country_code: US respondent_risk: 0 respondent_ud: 4489560a-507f-468a-ae4b-d81ea80fab5d time_zone: America/Chicago Surveys: - flag: 1 duplicate_initial_ud: 481cd5cf-88f1-44c2-8292-6b779b8a3a8e duplicate_potential: high duplicate_score: '100' country_mismatch: 0 failure_reason: '02' days_flag: 1 days_difference: 0 ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.