@smithy/core

Redact sensitive fields within list items and map values in schema-based logging.

Let clients offer a service default idle timeout to the request handler through updateHttpClientConfig, taken only when the handler has none of its own.

Export the shared writeKey helper and include headers named after Object prototype properties in canonical request signatures.

Add AbstractRpcV2Protocol, a shared abstract base for the Smithy RPC v2 JSON and CBOR client protocols, deduplicating their request framing and response status handling.

Add Smithy RPC v2 JSON protocol support: client protocol and JSON codec in @smithy/core, server protocol in @smithy/server-common, and the snapshot response serializer in @smithy/snapshot-testing.

Treat any non-200 response as an error in the Smithy RPC v2 JSON and CBOR client protocols, per the specification. RpcProtocol gains a protected isErrorResponse predicate (default unchanged: status >= 300) that both RPC v2 protocols override to status !== 200.

Add event stream header size validations

Cache schema-based detection of event streams

dbdacac: Keep the JSON string serializer's buffer reservation intact after 6-byte escape sequences so that the characters and closing quote that follow are always written within the buffer.

Add JSON codec (protocols/json) with v1/v2 serializers and deserializers, reviver/replacer precision handling, benchmarks, and the client protocol.

Fix endpoint cache key collision between empty-string and absent parameters

Fix for SDK ServiceException instanceof detection relating to mangled class names

Restore a compat name-string fallback in ServiceException instanceof for clients predating shapeId stamping, gated on a class-name length of at least 6