SPACE SDK versions and coverage

SDK	Version	Role	Package
Node.js	0.4.0	Backend	space-node-client
Python	1.1.0	Sync/async backend	space-python-client
Java	0.5.0	Backend, optional Spring integration	io.github.isa-group:space-java-client
React	0.4.0	Browser UI	space-react-client

The updated backend SDKs provide contract reads/creation/deletion, individual and group novations, usage increments, feature evaluation/consumption, pricing tokens, pricing YAML, new-contract and contracted versions, novation previews, conditional writes, optional idempotent retries, detailed refunds, event deduplication/resync and ES256 JWKS verification. They are integration clients, not wrappers for every administration endpoint of SPACE.

React provides feature gating, subscription/token hooks, updated claims, event metadata/resync when connected, and optional verification. Run privileged contract and consumption operations in your backend. Do not ship a management key to the browser. Token-only mode requires your backend to deliver new tokens and has no direct SPACE event stream.

Server capabilities are checked before requesting guarantees an older SPACE cannot provide. Event delivery has no replay guarantee: on resync, reload current state. Idempotency only protects the same key and request for the server's retention period. Preserve the key across job retries. For refunds, prefer the detailed method so a 200 response's skipped limits are visible.

These minor releases preserve existing public methods. Applications should adopt the user ID helper rather than interpreting sub, handle 412 by reloading the contract, and keep automatic retries opt-in. The server's ES256 mode needs signing keys configured; the expected issuer and organization must match the deployment. Verify the authenticated user as well as signature/claims.