2.1.7 Test (2.1.7) — Runtime Atlas

Claude Code 2.1.7 is the release that introduced customizable keyboard shortcuts, the showTurnDuration display toggle, and automatic MCP tool deferral, tested against version 2.1.9 on 2026-01-16.

"Keyboard shortcuts were hardcoded since launch. For a terminal tool used by developers who live in vim/emacs/tmux, not being able to customize keybindings was friction."

Epistemic status: changelog-derived, partially code-reviewed, partially untested. No full runtime verification was completed for most features. Frame all behavioral claims accordingly.

What shipped

Three user-facing features and one security fix landed together:

Customizable keybindings. Shortcuts are now stored in ~/.claude/keybindings.json and configurable via the /keybindings command. Previously all shortcuts were hardcoded. The format is a JSON map of key combos to action names (e.g., "ctrl+e": "submit").
showTurnDuration setting. A boolean in settings.json that hides the "Cooked for Xm Xs" message when set to false. Default is true. Joins IS_DEMO=1 as part of a growing "clean output for recordings" toolkit.
MCP tool search auto mode. When MCP tool descriptions would consume more than 10% of the context window, tools are no longer loaded upfront. They are instead discovered on-demand via an MCPSearch tool. Disable by adding MCPSearch to disallowedTools.
Security fix. Wildcard permission rules were incorrectly matching compound commands containing shell operators (&&, ||, ;, |). This was patched.

What the test found

Testing ran on 2026-01-16, against 2.1.9 (2.1.7 features backported). Results by feature:

Feature	Test method	Status
Customizable keybindings	Manual (interactive terminal required)	MANUAL -- not runtime-verified
`showTurnDuration`	Code review only	CODE REVIEW -- behavior inferred, not observed
MCP tool search auto mode	Not tested	UNTESTED -- requires a heavy multi-server MCP setup to hit the 10% threshold

No runtime failures were reported. The keybindings and turn-duration features were structurally confirmed via source inspection but not exercised in a live session.

Why it matters

Keybindings is the highest-impact feature for daily use: terminal multiplexer users (tmux, screen) routinely face key-binding collisions with hardcoded tools. The ~/.claude/keybindings.json file is a standard, discoverable location that follows established CLI conventions.

MCP auto-deferral is invisible to most users but scales gracefully. Users with five MCP tools will never notice the threshold; users accumulating dozens of tools benefit without any configuration change. The opt-out path (disallowedTools: ["MCPSearch"]) is explicit.

Caveats

The three headline features were not fully runtime-verified in this test run. The keybindings feature requires an interactive terminal session; the MCP deferral feature requires a sufficiently large MCP tool inventory to trigger the 10% threshold. Behavioral claims here derive from changelog text and source-level code review, not observed output. Treat specifics -- particularly the exact MCPSearch invocation path and the keybindings JSON schema -- as provisional until confirmed against a live 2.1.7+ session.