v1.7.0-pre.2
Pre-release
guglielmo-san
Guglielmo Colombo
v1.7.0-pre.2
This is a follow-up pre-release on top of v1.7.0-pre.1, still targeting protocol version 2026-07-28. It rounds out the previous release with conformance-test coverage on both client and server, tightens spec compliance and introduces first-class support for custom JSON-RPC methods.
Custom JSON-RPC methods
The SDK now supports registering non-standard JSON-RPC methods end-to-end. Servers can register handlers with AddReceivingCustomMethod and clients can invoke them via AddSendingCustomMethod.
- mcp: Allow registration of custom JSON-RPC methods by @guglielmo-san (#956)
Conformance tests
Both the client and server implementations are now exercised by the official MCP conformance test suite as part of CI.
- mcp: add integration for server conformance tests by @guglielmo-san (#1054)
- mcp: add conformance tests on client by @guglielmo-san (#1063)
Protection agains OOM attacks
The streamable HTTP transport now enforces a configurable request body size limit to protect servers against OOM-style attacks from oversized payloads.
- mcp: enforce body size limit in Streamable connection by @guglielmo-san (#1055)
Spec compliance fixes
Several smaller fixes bring the implementation closer to the spec.
- mcp: do not exclude Notifications from carrying InitializeParams in Meta by @guglielmo-san (#1049)
- mcp: cap negotiated protocolVersion in legacy initialize to
protocolVersion20251125by @guglielmo-san (#1051) - mcp: make NotificationSubscriptions a mandatory field by @guglielmo-san (#1050)
- fix: extra wrapper for input response map by @yarolegovich (#1045)
- mcp: do not enforce TTL on cached tool by @guglielmo-san (#1053)
- mcp: block server initiated requests (SEP-2322) by @guglielmo-san (#1057)
Full Changelog: v1.7.0-pre.1...v1.7.0-pre.2