Ultra Config switches your whole Claude Code setup between five profiles mid-session

Posted on Oct 19 • Originally published at Medium

I keep changing the same handful of things in Claude Code depending on what I am doing. Cheap and quiet when I am grinding through a long refactor. The most capable model and maximum effort when the problem is actually hard. Everything asking first when I am working in someone else’s repo. Those are different values in different places, and I was editing them by hand every time.

Ultra Config is a Mod I built so that it is one press instead.

Each profile is a list of settings with a reason attached to every one of them. This is what they set:

The pane shows how much of a profile is already in force as a fraction, 3/11, and marks it active when all of it is. Open a profile and every line is either a change (old value struck through, new value, and why), something already set, or something skipped.

Token saver is the one I reach for most, and it is worth noticing what it is: the same model split I posted about last week, without installing a separate setting for it.

npx claude-code-templates@latest --mod productivity/ultra-config Enter fullscreen mode Exit fullscreen mode It needs Claude Code 2.1.287 or later, which is the version where Mods are on by default, and a trusted project folder.

Everything in the pane is a press, not a menu. There are no tabs and no arrow-key navigation, which matters because Claude Code already uses the left arrow for its own agents view.

In the fullscreen layout the pane docks next to the transcript, which needs /tui fullscreen and at least 110 columns. On the classic layout it sits above the prompt. In Claude Desktop it draws in the session's side panel.

This is the part worth understanding before you let something rewrite your configuration.

Rows that exist in Claude Code’s own settings menu, like the model, the permission mode, the output style or auto-compact, are set through the same path the menu uses. Claude Code decides which file they go in, exactly as if you had changed them yourself.

Effort is saved per model, the way /effort saves it, under modelSettings in ~/.claude/settings.json. That keying matters: since Claude Code 2.1.251, a top-level effortLevel is ignored by Opus 5.5 and later models, so the Mod never writes one. A model id containing a dot, which is what you get on Bedrock and Vertex, cannot be saved this way, and the effort then applies to that one request only.

Four keys have no menu row, so they are written straight into ~/.claude/settings.json:

{ "env": { "CLAUDE_CODE_SUBAGENT_MODEL": "haiku", "MAX_MCP_OUTPUT_TOKENS": "10000" }, "permissions": { "disableBypassPermissionsMode": "disable", "deny": [ "Read(./.env)", "Read(./secrets/**)", "Read(~/.ssh/**)" ] } } Enter fullscreen mode Exit fullscreen mode Before each of those writes the file is copied to settings.json.ultra-config.bak, and a settings.json that is not valid JSON is never overwritten: those steps are skipped and the pane says why. The last 20 activations are kept in the plugin's store, so undo still works after a restart and puts back the values it changed, leaving alone any deny rule you already had.