Context Meter: Claude Code Context Usage Status Line

Context Meter is a Claude Code context usage status line. It writes one compact line into the status line: ctx 42% · 5h 23% · 7d 61.5% · $1.20. That is how full the context window is, how much of your 5-hour and 7-day plan windows you have used (on a subscription), and what the session has cost so far. When the context reaches 80 percent, a toast warns you once so you can /compact or /clear before Claude starts losing earlier detail.

The point is to stop guessing. You no longer need to run /cost or /context to know whether a long task will fit, and the warning comes early enough to compact on your own terms. Requires Claude Code 2.1.287 or later.

The recording starts a session with the mod loaded. The status line shows ctx – until the first answer, then fills in the context percentage, the plan windows and the cost after the turn completes.

Pick one of the methods in the install block. Nothing needs configuring; the defaults show everything the account provides.

The whole mod is three hooks and one refresh function. From hooks/register.ts:

async function refresh($: EngineInterface, meter: Meter): Promise<void> {
  // No `breakdown`: the status-line figures alone, which cost no request.
  const usage = await $.session.usage()
  $.ui.status(formatMeter(usage, meter))
  const percent = contextPercent(usage)
  const step = warnStep(percent, meter.warnAtPercent, meter.warned)
  meter.warned = step.warned
  if (step.toast) {
    $.ui.toast(`Context is ${percent}% full. Consider /compact or /clear soon.`)
  }
}

$.session.usage() returns the context tokens and window, the plan rate limits and the cost. Called without a breakdown, it reads numbers Claude Code already has, so the meter is free to run as often as it likes. formatMeter in hooks/format.ts builds the text and drops any figure the engine does not have rather than printing zero. warnStep remembers whether it already warned, so the toast appears once per crossing; after a compaction brings the context back under the threshold, it can warn again.

refresh is called from session.start (which also starts a $.clock.every timer), from turn.complete for main-loop turns only, and from session.compact. session.compact can cancel a compaction, so its hook awaits next(e) first and carries a .catch that hands back what next settled to. The meter never stops a compaction.

Set these options in /config. format: verbose spells the line out as Context 42% (84k/200k) · 5-hour 23% · 7-day 61.5% · Cost $1.20. The labels live in the LIMIT_LABELS table in hooks/format.ts, so that is the place to rename 5h or 7d. The warning text is the template string inside refresh.

The only badge is Changes the UI: the mod writes the status line and shows a toast. It does not run commands, read or write files, use the network, read your prompts or call the model. That makes it one of the safest mods you can install, and a good first one.

To turn it off, run /plugin disable cm-context-meter. To start a session with every mod off, use claude --safe-mode.

Tested with Claude Code 2.1.291 in the terminal on macOS. If the meter does not appear:

• Check claude --version; mods need 2.1.287 or later.
• Make sure the mod is enabled in the Installed tab of /plugin.
• After a shell install, run /reload-plugins in sessions that were already open.
• Another mod or a custom status line command can share the line. Disable other status mods briefly to see whether the text is being crowded out.
• No plan figures on an API key is expected behaviour.

The cost figure is the same session estimate that /cost totals; it is not an invoice.