MCP 2026-07-28 spec: which version does Sume's hosted server speak?
The 2026-07-28 MCP revision is out and Claude Code speaks it. Sume's hosted server negotiates 2025-03-26, 2025-06-18 and 2025-11-25, not 2026-07-28.
Sume's hosted MCP server, https://mcp.sume.com/mcp, negotiates three protocol versions in its code today: 2025-03-26, 2025-06-18 and 2025-11-25, with 2025-11-25 as the default. It does not implement the 2026-07-28 revision, so do not describe it as doing so. Clients connect through the version negotiation they already use.
The 2026-07-28 facts below come from the MCP project's release post, and the client fact from Claude Code's changelog, both read 2026-09-29. The server facts come from Sume's MCP code, which reports server name sume-remote-mcp, version 0.4.0.
What did the 2026-07-28 revision change?
The MCP blog lists the release date as July 28, 2026 and describes these changes.
| Area | What the post describes |
|---|---|
| Core | A stateless core |
| Long work | A Tasks extension with tasks/get and tasks/update |
| Routing | Mcp-Method and Mcp-Name headers |
| Caching | List caching through ttlMs and cacheScope |
| Authorization | Hardening, including RFC 9207 and Client ID Metadata Documents |
| Deprecated | Roots, Sampling and Logging |
Which versions does Sume's server accept?
It reads the protocol version the client sends at initialize and answers with a version it supports. Its capabilities are tools with listChanged set to false. There is no Tasks support on the server, so a long clip is not a protocol task: it is a job id you wait on with jobs_wait.
| Version | Supported |
|---|---|
| 2025-03-26 | Yes |
| 2025-06-18 | Yes |
| 2025-11-25 | Yes, default |
| 2026-07-28 | No |
Do clients on the new revision still connect?
Claude Code's changelog says v2.1.284 added MCP URL-mode elicitation on 2026-07-28 protocol connections, so that client can speak the new revision. Whether it falls back to an older one for a given server is client behavior; this site has not tested every client, so check your client's connection status after adding the server.
If a connection fails, the server's mcp_health tool (once connected) and the client's own logs are the first places to look; the failure is usually authentication, not the protocol version.
What should I not assume?
Do not assume Tasks, list caching or the new routing headers are available on the hosted server. Do not assume a client on the new revision changes what tools Sume lists. The tool set, the spend controls and the job model are the same for every client version.
Sources
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