Claude Code 2.1.260 adds a /diff panel and cache-miss diagnostics
The release lands headless /reload-plugins and /advisor, fixes caching on Fable 5.1 and 1M-context auto-compact, plus 2.1.259's managed MCP servers.
Copy markdown
See your diff without leaving the chat
Fullscreen mode gets a `/diff` toggle that shows your uncommitted changes in a panel beside the conversation — review exactly what the agent edited without flipping to a terminal or your editor.
/cost now explains a cache miss
`/cost` and the status line now name the likely cause when a prompt-cache miss inflates a turn — the gap between paying cache-read rates and full input rates, which adds up fast on long agent sessions.
New commands for headless and desktop
`/reload-plugins` works in headless sessions now, and a text-based `/advisor` lands for desktop and headless — handy if you drive Claude Code from CI or scripts instead of an interactive terminal.
Cache fixes for Fable 5.1 and 1M models
A caching bug on Claude Fable 5.1 that skipped post-tool-result context is fixed, and auto-compact improved for 1M-context models — both stop you from re-paying for tokens on long runs.
Permission rules that were quietly broken
2.1.260 fixes file-permission rules containing parentheses being dropped and Bash checks that auto-approved certain zsh commands. Managed settings that failed to load for some Enterprise/Team users on legacy API keys are fixed too.
2.1.259: orgs can push MCP to everyone
The prior release added a `managedMcpServers` setting so organizations can hand every user the same HTTP/SSE MCP servers, `--permission-prompts none` to auto-deny on unattended hosts, and `--json` on `claude plugin validate` for CI.
Elsewhere: Copilot retires four models Oct 2
GitHub Copilot will deprecate Gemini 3.5 Flash, Gemini 3.6 Flash, Kimi K2.7 Code, and Claude Opus 4.7 on October 2 — repoint workflows to Gemini 3.8 Flash, Kimi K3, and Claude Opus 5 before then.