Formbricks

Formbricks provides targeted in-product surveys with audience segmentation (show survey when user triggers X event, has attribute Y, or is in cohort Z), a in-app widget SDK, and a REST API for managing survey definitions and retrieving responses. For agents, primary use cases: pull response data for analysis (NPS scores, CSAT ratings, open feedback), manage survey configurations programmatically, and update person/contact state (attributes, events) that drive survey targeting. Open-source and self-hostable. Growing alternative to Sprig, Hotjar Surveys, and Delighted for in-product feedback. Confidence is docs-derived.

REST API at app.formbricks.com/api/v1 (Cloud) or self-hosted base URL. Resources: surveys, responses, environments, people (contacts), attributes. GET /api/v1/management/surveys lists surveys with status, question count, and response count. GET /api/v1/management/surveys/{id}/responses paginates survey responses. POST /api/v1/client/environments/{envId}/people creates/updates a person with attributes (user_id, email, plan, etc.). POST /api/v1/client/environments/{envId}/events records a custom event for survey targeting. Response payloads are JSON with survey/response objects.

Management API (survey/response management): API key via x-api-key header. Client API (in-product SDK calls): environment ID + public client key. API keys and environment IDs from Formbricks Settings → API Keys. Management keys are org-scoped; client keys are environment-scoped (production vs. development). HTTPS enforced on Cloud; operator-configured for self-hosted. No OAuth2 for direct API access.

Standard HTTP status codes with JSON error bodies. 401 for invalid API key, 404 for missing survey/response, 400 for validation errors. Rate limits not prominently documented. Response pagination via page and per_page params. Self-hosted reliability depends on deployment (Docker with PostgreSQL and Redis). Formbricks Cloud uptime at status.formbricks.com. Survey targeting evaluation is client-side (SDK); server-side response storage is reliable.

formbricks.com/docs covers API reference, self-hosting guide (Docker, Railway, Vercel), SDK integration (React, Next.js, JavaScript), survey targeting logic (attributes, events, segments), and getting-started tutorials. Documentation is adequate and actively maintained. Getting started is fast with Formbricks Cloud (free tier) or Docker. Open-source community on GitHub and Discord. Weekly releases with changelog.