You know that absolute pain where, uh, where you are watching Claude Code refactor
six files at once, and you are frantically pounding alt tab or opening a second
terminal window just to run git diff to see what it actually touched?
Today's episode is brought to you by Jellypod AI, but man, Anthropic just killed
that tab dance completely in Claude Code version 2 point 1 point 260.
Wait, did they finally put an actual diff right in the terminal interface?
They did!
It is a live, split screen diff panel.
So if you are running in fullscreen mode, you just type slash diff,
and boom, a panel snaps open right beside your active conversation.
Side by side?
Like, in a standard terminal emulator?
Yeah!
Right in the terminal.
As Claude writes or edits code, your uncommitted changes update in real time in that
side panel.
I was doing a big React component refactor yesterday, and while the agent was still
streaming its response, I caught it silently deleting an export prop that I actually
needed.
I saw it hit the diff pane before the turn even finished, so I could jump in
instantly.
That is huge.
And if your conversation buffer gets totally cluttered with long tool outputs,
can you clear the screen without losing that diff view?
Spot on.
You hit control L or command K in fullscreen, and it clears your transcript
scrollback like a standard terminal clear, but the live diff panel stays pinned
right where it is.
Now, just a quick operational heads up on that split view, your terminal geometry
actually needs enough horizontal columns to render both panes,
or it won't trigger cleanly.
Makes total sense.
You can't squeeze a full split diff into an eighty column window.
But okay, speaking of under the hood visibility, the update to slash cost is what
caught my eye in the 2 point 1 point 260 release notes.
Ah, the prompt cache miss diagnostics!
Yes!
We had this pipeline in our CI setup where prompt cache hit rates were just randomly
plunging, and our API bill was spiking.
Before this patch, the prompt cache field in slash cost just told you,
hey, you missed the cache.
It never told you why.
Right, it was just a blank number glaring at you.
Exactly.
But now, both slash cost and the status line's prompt cache field explicitly break
down the exact root cause.
It will literally tell you, hey, your tool definitions changed,
or your system prompt was modified, or you simply idled past the time to live limit.
Turns out it was an MCP tool server updating its schema on launch,
right?
It, it, it was!
One of our Model Context Protocol servers was sending slightly dynamic tool
descriptions on reboot, invalidating the entire cached prefix every single time.
Having that exact reason explicitly stated in slash cost saved us hours of digging
through API payload logs.
That is so satisfying.
And look, if you are running automated or headless sessions through the Agent SDK or
Remote Control, they added some big quality of life tweaks there too.
You can now use a text form slash advisor command, like slash advisor,
followed by the model name, or slash advisor off, right inside headless sessions.
Plus slash reload plugins is now officially available for SDK users.
Oh, that saves restarting the whole headless process when you tweak a custom plugin!
Precisely.
Though do watch out if you run zsh scripts in auto mode, they patched a security
edge case where command substitutions hidden inside assignments like REPORTTIME or
DIRSTACKSIZE were auto approving.
Now those will properly prompt you for approval.
Good security catch.
So between live split screen diffing with slash diff and cache debugging in slash
cost, version 2 point 1 point 260 gives us way better visibility across the board.
No more tab switching just to check your code edits.
Go update your binary and give slash diff a spin!