Follow Discord
Sweep 22 Oct 2026 · 04:32Z Build v2.1.308 527 read Stable v2.1.308 Latest v2.1.308 Next v2.1.308 Feeds RSS JSON llms.txt llms-full.txt Unofficial
HomeReleasesv2.1.236entry #61

Claude Code v2.1.236 ·

MCP protocol auto-negotiation now covers the ccr-proxy transport, off by default

The ccr-proxy MCP transport can negotiate protocol versions, but stays on legacy unless a flag is turned on.

Nothing to try yet Notable New Features
JSON All of v2.1.236
Nothing to try yetTier: how much it should matter to you
2Useful: my rating, 1 to 5
3Signal: worth watching, 1 to 5
MCPArea: what it touches
New FeaturesKind: in v2.1.236,
What probably matters to youSection of the release

Protocol auto-negotiation for the ccr-proxy MCP transport is built but gated off, so behaviour is unchanged.

What

The ccr-proxy MCP transport used to fall through to the legacy branch alongside sse, ws and ide. It now has its own check gated on tengu_mcp_protocol_negotiation_ccr: with the flag on it negotiates in auto mode with a probe, and with it off it stays on legacy exactly as before.

Details
  • Fallback is false, so absent a server value nothing changes.
Evidence

tengu_mcp_protocol_negotiation_ccr

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Read from
Feature flag
tengu_mcp_protocol_negotiation_ccr Not enough to say

Nothing here resolved what this flag was doing on this version, so nothing here should be read as on or off.

This account: no value returned · anonymous baseline: no value returned · compiled default in v2.1.236: off

Read once, for one account on one subscription tier, against v2.1.236. It isn't a statement about your account. What a flag value here can and cannot tell you

What has happened since
Flag reading moved The flag server now returns on for tengu_mcp_protocol_negotiation_ccr, read as this account. A reading is one sample. Claude Code evaluates its flags remotely, so no client sees the targeting rule behind a value and this says nothing about your account.
Flag reading moved The flag server now returns nothing at all, having stopped carrying it for tengu_mcp_protocol_negotiation_ccr, read as this account. A reading is one sample. Claude Code evaluates its flags remotely, so no client sees the targeting rule behind a value and this says nothing about your account.

See this across every release →

How sure we are
One source agreesOne thing we can check says the same as this entry.
The name it cites is new in this buildNew in this build: tengu_mcp_protocol_negotiation_ccr

See this entry in the whole of v2.1.236 →

Feedback