MCP's 12-month deprecation window: what Sume tool authors can rely on

The 2026-07-28 MCP changelog introduces a 12-month deprecation policy (SEP-2596) and, under it, deprecates HTTP+SSE as well as the Roots, Sampling and Logging features (SEP-2577). For someone who writes tools against Sume's hosted MCP, the safe part is the tool contract: Sume tells you the live tool set with tools_list and one tool's schema with tools_schema, so you read the contract at run time instead of baking it in.

What was deprecated

What Sume documents for tool authors

Sume's hosted MCP is a remote HTTP endpoint and its docs do not describe Roots, Sampling or Logging, so I make no claim about whether any Sume tool uses them. What the docs do commit to is a naming and discovery contract: live tool ids are underscore names, dotted aliases such as tools.list are canonicalized to them, and retired aliases are named (image-generations_create became generate_image, video-router_create became generate_video).

A rule set for tool authors

• Discover, do not hard-code. Call tools_list and tools_schema and build prompts from the result.
• Use the current ids: generate_image and generate_video, not the retired aliases.
• Treat Image 1.0 and Video 1.0 as REST-only. They are not in tools_list.
• Keep the safety gates: idempotency_key on write and paid tools, dry_run and max_spend_usd for spend.
• Do not rely on a long-lived stream. Sume documents bounded waits: jobs_wait has a default of 50 seconds and a cap of 55.

What a 12-month window buys

It gives you a planning horizon for protocol changes: a deprecated feature is announced before it goes. It does not tell you when a particular server will drop it. For Sume, watch the MCP docs and the tools_list output when you upgrade a client, and re-check this against the changelog linked in sources.

Worked example: a deprecation calendar

If a feature is announced as deprecated on a given day and the policy is 12 months, the earliest planned removal is a year later. A feature deprecated in the 2026-07-28 revision would then be removable no earlier than the summer of 2027 under that policy. I derived that from the policy figure, and the changelog does not give a removal date for each item. Put the real dates on your calendar when the spec or a server announces them.

For your own tools, apply the same courtesy: when you retire a tool name, keep the old name resolving and say so, as Sume does for generate_image and generate_video.