# 2026-06-30 Spec Compliance Track C# SDK compliance with all SEPs scoped to the [2026-06-30 MCP spec release](https://plan.modelcontextprotocol.io/releases/1). ## SEPs ### Final - [ ] [SEP-1730: SDK tiers definition](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/1777) - Governance/process — defines tier requirements for SDKs, no code change - [ ] [SEP-1865: MCP Apps - Interactive User Interfaces for MCP](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/1865) - https://github.com/modelcontextprotocol/csharp-sdk/issues/1431 - [x] [SEP-2133: Extensions framework for MCP](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2133) - completed in https://github.com/modelcontextprotocol/csharp-sdk/pull/1317 - [ ] [SEP-2164: Standardize resource not found error code (-32602)](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2164) - https://github.com/modelcontextprotocol/csharp-sdk/issues/1540 - [ ] [SEP-2207: OIDC-flavored refresh token guidance](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2207) - No SDK support required - [ ] [SEP-2243: HTTP Standardization](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2243) - https://github.com/modelcontextprotocol/csharp-sdk/issues/1541 ### Accepted - [x] [SEP-414: Document OpenTelemetry Trace Context Propagation Conventions](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/414) - no SDK changes needed (already compliant) - [ ] [SEP-837: Update authorization spec to clarify client type requirements](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/837) - https://github.com/modelcontextprotocol/csharp-sdk/issues/1545 - [ ] [SEP-2260: Require Server requests to be associated with a Client request](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2260) - SDK support needed is TBD -- waiting on conformance tests - [ ] [SEP-2322: Multi Round-Trip Requests](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2322) - https://github.com/modelcontextprotocol/csharp-sdk/issues/1546 - [ ] [SEP-2350: Clarify client-side scope accumulation in step-up authorization](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2350) - https://github.com/modelcontextprotocol/csharp-sdk/issues/1547 - [x] [SEP-2351: Explicitly specify RFC 8414 well-known URI suffix for MCP](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2351) - No SDK support needed — clarification only, existing discovery logic already compliant - [x] [SEP-2352: Clarify authorization server binding and migration](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2352) - No SDK support needed — per-instance architecture already maintains separate state per AS - [ ] [SEP-2484: Require Conformance Tests for Standards Track SEPs to Reach Final Status](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2484) - Process — requires conformance tests in a separate repo, not SDK code - [ ] [SEP-2567: Sessionless MCP via Explicit State Handles](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2567) - https://github.com/modelcontextprotocol/csharp-sdk/issues/1548 - [ ] [SEP-2575: Make MCP Stateless](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2575) - https://github.com/modelcontextprotocol/csharp-sdk/issues/1549 ### In Review - [ ] [SEP-2106: Tools `inputSchema` & `outputSchema` Conform to JSON Schema 2020-12](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2106) - #1550 - [ ] [SEP-2145: Standardize `tools/call` failure reporting](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2145) - #1551 - [ ] [SEP-2200: Clarify tool result content visibility](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2200) - #1552 - [ ] [SEP-2356: File input support for tools and elicitation](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2356) - [ ] [SEP-2468: Recommend Issuer (iss) Parameter in MCP Auth Responses](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2468) - [ ] [SEP-2549: TTL for List Results](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2549) - [ ] [SEP-2577: Deprecate Roots, Sampling, and Logging](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2577) - [ ] [SEP-2596: Specification Feature Lifecycle and Deprecation Policy](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2596) - Process — defines lifecycle mechanics (Active→Deprecated→Removed) for spec features - [ ] [SEP-2663: Tasks Extension](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2663)
2026-06-30 Spec Compliance
Track C# SDK compliance with all SEPs scoped to the 2026-06-30 MCP spec release.
SEPs
Final
Accepted
In Review
inputSchema&outputSchemaConform to JSON Schema 2020-12tools/callfailure reporting