CLI Config Describe

`ed config describe`

Explains one setting. This is what to read before writing something you are unsure of.

ed config describe <key> [--json]

Argument	Type / values	Default	What it does
`key`	a catalogue key	required	The setting to explain

Option	Type / values	Default	What it does
`--json`	flag	`false`	Emit JSON on stdout

$ ed config describe limitsProvider
limitsProvider
  Provider shown first in the limits UI.
  type     string
  group    limits
  scope    shared
  allowed  claude, codex
  default  claude
  value    claude

The allowed line appears only when the setting has an allowed list, and a final read only line appears only for the 23 keys the app owns. --json emits the same object ls and get emit, which always carries every field:

{
  "allowed": [
    "claude",
    "codex"
  ],
  "default": "claude",
  "group": "limits",
  "isSet": true,
  "key": "limitsProvider",
  "readOnly": false,
  "scope": "shared",
  "summary": "Provider shown first in the limits UI.",
  "type": "string",
  "value": "claude"
}

ed config describe clipboardPopupAt
ed config describe budgetMode --json

isSet is the same test --changed and export use: there is a stored value and it differs from any registered default. Unknown keys exit 3 with the same near-match hint get gives.