Documentation Underlay has a small API surface. These docs are the SDK. Read them, point your LLM at them, or just curl the endpoints. For a machine-readable version, see llms.txt .
API reference Overview Auth, rate limits, error handling Accounts Profiles, organizations, API keys Collections Create, list, update, delete, transfer, fork Versions Delta push, version history, records, manifests, diff Files Upload, verify and download content-addressed files Records and schemas Records by hash across collections, provenance, schema discovery and labels Sync and integrations Tree sync, exports, webhooks, ARKs, storage mirrors, health, abuse reports Protocol Overview Protocol v2: scope, conformance, terminology Records and schemas Canonical JSON, input rules, record and schema hashes, validation, files Trees and versions Key order, trees, access sets, the version root, semver Repositories Repository layout, the signed version log, packs, the reads a server provides Push and pull Delta push, clients without a copy, pull, errors, security considerations