Token + cost meter

Keep a live count of tokens / cost / files-changed in the notch while an agent works, so you can glance at the meter instead of digging through logs.

From an MCP agent

Have the agent call update_status whenever its running totals change (replaces the previous line, same source):

mcp

update_status({
  text: "142k tokens · $0.38 · 4 files",
  source: "Claude",
  icon: "number"
})

bash

tellie update "142k tokens · \$0.38 · 4 files" --source Claude --icon number

Because update replaces in place (keyed by source), you can fire it as often as you like, the meter just updates; it never piles up.
Pair with the agent lifecycle recipe so the meter clears when the turn ends.
End with a milestone: tellie flash "Done · 198k tokens · \$0.51" --source Claude --icon checkmark.circle.

A tokens / cost / files meter ticking up in place as the agent works, then settling on the final total.