Fern
buildwithfern.comA platform that generates SDKs, interactive API documentation, and a CLI from an OpenAPI or Fern definition spec.
The Fern API has freemium pricing; offers a free tier (Hobby plan $0/mo free forever: 2 team members, 250 AI credits, custom domain, API explorer); rate limits: Ask API token is a short-lived JWT (5 min expiry, 10 requests) used for rate-limiting. Verified 2026-07-08 with per-field source links.
Base URL
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no sourceAuth
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no sourceFree tier
Hobby plan $0/mo free forever: 2 team members, 250 AI credits, custom domain, API explorer
buildwithfern.com ↗Pricing
Docs: Hobby $0/mo, Team $150/mo (yearly, 25% savings vs monthly), Enterprise custom. Basic (free), Pro, and Enterprise (contact sales) plans also described.
buildwithfern.com ↗Rate limits
Ask API token is a short-lived JWT (5 min expiry, 10 requests) used for rate-limiting
buildwithfern.com ↗OpenAPI spec
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no source