> ## Documentation Index
> Fetch the complete documentation index at: https://developers.respondent.io/llms.txt
> Use this file to discover all available pages before exploring further.

# API FAQ

> Common questions and tips for maximizing your integration

1. ### How do I test the respondent flow in staging without recruiting real participants?

   You create a participant profile in staging via our [profile creation endpoint](/profiles/create-test-participant-staging-only). You can then invite that profile by following these steps:

   1. Log into the staging participant profile in one browser tab.
   2. In another tab (recommend opening in incognito), log into the researcher side.
   3. Open a published project and look for the **Share** button in the top-right corner.
   4. Copy the project link and switch back to the staging participant profile tab.
   5. Paste the link into the search bar of the staging participant profile. The staging participant should then be able to access the screener.

2. ### What is an externalResearcherId?

   An externalResearcherId is a custom identifier that the API partner assigns to researchers when creating projects via our API.

3. ### What parameters are appended to the task URL?

   * `respondent_profile_id`
   * `respondent_project_id`
   * `respondent_screener_response_id`
   * `respondent_user_id`
   * `month`

4. ### What are some tips and tricks to maximise your integration?

   * `autopay` is set to `true`. If set to false, you will need to manually login onto our DIY platform to process payment or use our [manual payout endpoint](/screener-responses/trigger-manual-payout) with payoutCount: 1.
   * Use the [Retrieve Audience Size Estimate](/projects/retrieve-audience-size-estimate) endpoint to test feasibility — it can be called multiple times as you adjust filters and signals.
   * Use the [Qualify Participant](/screener-responses/qualify-participant) endpoint: For qualifying or disqualifying participants based on their screener responses—any disqualified participant will automatically be backfilled.
   * Use the [Mark As Rejected](/screener-responses/mark-as-rejected)endpoint: For when the participant response to the study does not meet researcher’s criteria.
   * Use the [Report Participant](/screener-responses/report-participant) endpoint: For flagging participants for inappropriate behavior. Reported participants won’t appear in future projects.
   * Enable messaging with participants through our [messaging flow](/messaging/create-a-conversation) to boost show and task completion rates.
   * Enable the past participant database feature to unlock the ability to filter out participants who’ve taken part in previous studies, or to selectively re-invite high-quality (favorite) participants.
   * When a project reaches 3x the target number of participants, it is automatically paused. To continue recruitment, simply unpause the project.