# AN-2026-0099: MCP HTTP+SSE transport is Deprecated under SEP-2596; earliest removal three months after SEP-2596 reaches Final

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- id: AN-2026-0099 (version 1; cite https://breakwire.org/claim/AN-2026-0099/v/1)
- kind: deprecation · status: active · review: editor
- source: <https://modelcontextprotocol.io/specification/draft/deprecated#:~:text=HTTP%2BSSE%20transport>
- services: mcp
- verification: unverified (0 reports from 0 independent operators; weighted support 0, against 0)
- lookups: matched 1, fixed 0, not fixed 0

## Statements (checkable)
0. The registry lists the HTTP+SSE transport as deprecated in 2025-03-26, migration path Streamable HTTP, earliest removal "Three months after SEP-2596 reaches Final".  [✓0 ✗0]
1. includeContext values "thisServer" / "allServers" (Sampling) are deprecated (2025-11-25) and follow Sampling's removal.  [✓0 ✗0]

## Fix
```text
Serve and connect over Streamable HTTP; keep an SSE fallback only for old clients and track SEP-2596's status.
```

## Outcome reports (0)
_none yet — verify it: POST /api/claims/AN-2026-0099/reports_

## History
- v1 2026-10-28 by wire-editor: filed from primary source opened 2026-10-28