Preserve API Contracts

Ensure API contracts are explicit, semantically consistent, and forwarded end-to-end across layers.

Practical rules: 1) Don’t change semantics without changing the contract: if a request header field’s meaning changes, either keep the original meaning or rename the header (or add a new header) so the backend contract remains unambiguous. 2) Forward every field through every projection/copy: when a new request/response field is added, verify all downstream event copies and runtime conversions preserve it (including “pending_*”/projector paths). 3) Expose RPC operations consistently: operations used by clients must be registered/available through the public hub/client surface; otherwise runtime behavior can break or silently diverge. 4) Carry explicit identity/scope tokens: prefer passing an explicit scope/account token through snapshots/calls to prevent accidental account switching or reliance on repeated implicit checks. 5) Use self-describing interfaces in client code: avoid positional booleans in function signatures; prefer an options object (e.g. { refresh: true, userInitiated: true }). 6) Pin and normalize API versions/URLs: when calling external services, use the correct versioned endpoints and normalize paths (trailing slashes, optional prefixes) to avoid environment-specific breakage.

Example (options object instead of boolean flags):

// before (ambiguous)
load(true, true)

// after (self-describing)
load({ refresh: true, userInitiated: true })