context-meter by vumichien: Claude Code mod code

What it does

Draws a band above the prompt, toasts
Adds /context-meter
Hooks session.compact, session.measure, session.start, turn.complete and 1 more
Keeps its own state between turns

Good points

No network calls
Starts no processes
Written in TypeScript
Has a desktop-specific branch

Code to start from

A starter ModsCode writes from the drawing it read, and the mod's own lines that draw, where there are any.

Starter (register.tsx)

import type { Register } from 'claude-code'

// Drawn like context-meter by Chien Vu Minh (band, toast), as ModsCode read it from the mod's code:
// https://modscode.com/claude-mods/mods/vumichien-context-meter/
// Written by ModsCode from that reading, not copied from the mod: use it as you like.
// Each value below stands for one the mod works out at run time; put in your own.
export const register: Register = on => {
  // the band above the prompt; what else goes there is drawn under it
  on('ui.render', { component: 'AbovePrompt' }, async ($, e, next) => {
    const { Box, Text, Button } = $.ui.resolve(e)
    const head = '…'
    const name = '…'
    const tokens = '…'
    const share = '…'
    const tokens2 = '…'
    const tokens3 = '…'
    const tokens4 = '…'
    const tokens5 = '…'
    const tokens6 = '…'
    const tokens7 = '…'
    const tokens8 = '…'
    const tokens9 = '…'
    const text = '…'
    const said = '…'
    return (
      <Box flexDirection="column">
        <Box justifyContent="space-between">
          <Text wrap="truncate">
            {`${head} `}
          </Text>
          <Button label="Compact" hotkey="c" />
        </Box>
        <Box>
          <Text>
            ░░░░░░░░
          </Text>
          <Text>
            ░░░░░░░░
          </Text>
          <Text>
            ░░░░░░░░
          </Text>
        </Box>
        <Box>
          <Box>
            <Text>
              {"   ■ "}
            </Text>
            <Text>
              {`${name} `}
            </Text>
            <Text bold>
              {tokens}
            </Text>
            <Text dimColor>
              {` ${share}`}
            </Text>
          </Box>
          <Box>
            <Text>
              {"   ■ "}
            </Text>
            <Text>
              {`${name} `}
            </Text>
            <Text bold>
              {tokens2}
            </Text>
            <Text dimColor>
              {` ${share}`}
            </Text>
          </Box>
          <Box>
            <Text>
              {"   ■ "}
            </Text>
            <Text>
              {`${name} `}
            </Text>
            <Text bold>
              {tokens3}
            </Text>
            <Text dimColor>
              {` ${share}`}
            </Text>
          </Box>
        </Box>
        <Box>
          <Box>
            <Text>
              {"   ■ "}
            </Text>
            <Text>
              {`${name} `}
            </Text>
            <Text bold>
              {tokens4}
            </Text>
            <Text dimColor>
              {` ${share}`}
            </Text>
          </Box>
          <Box>
            <Text>
              {"   ■ "}
            </Text>
            <Text>
              {`${name} `}
            </Text>
            <Text bold>
              {tokens5}
            </Text>
            <Text dimColor>
              {` ${share}`}
            </Text>
          </Box>
          <Box>
            <Text>
              {"   ■ "}
            </Text>
            <Text>
              {`${name} `}
            </Text>
            <Text bold>
              {tokens6}
            </Text>
            <Text dimColor>
              {` ${share}`}
            </Text>
          </Box>
        </Box>
        <Box>
          <Box>
            <Text>
              {"   ■ "}
            </Text>
            <Text>
              {`${name} `}
            </Text>
            <Text bold>
              {tokens7}
            </Text>
            <Text dimColor>
              {` ${share}`}
            </Text>
          </Box>
          <Box>
            <Text>
              {"   ■ "}
            </Text>
            <Text>
              {`${name} `}
            </Text>
            <Text bold>
              {tokens8}
            </Text>
            <Text dimColor>
              {` ${share}`}
            </Text>
          </Box>
          <Box>
            <Text>
              {"   ■ "}
            </Text>
            <Text>
              {`${name} `}
            </Text>
            <Text bold>
              {tokens9}
            </Text>
            <Text dimColor>
              {` ${share}`}
            </Text>
          </Box>
        </Box>
        <Text wrap="truncate" color="error">
          {text}
        </Text>
        <Text color="warning" wrap="truncate">
          {`context-meter: ${said}`}
        </Text>
        {await next(e)}
      </Box>
    )
  })

  on('session.start', async ($, e, next) => {
    const said = '…'
    await $.ui.toast(`context-meter: ${said}`)
    return next(e)
  })
}

The mod's own code

Shown under the mod's licence (MIT); its text is below. Keep the notice if you copy these lines.

plugins/context-meter/hooks/register.tsx lines 180–244 · Band

plugins/context-meter/hooks/register.tsx:180

  on('ui.render', { component: 'AbovePrompt' }, async ($, e, next) => {
    const below = await next(e)
    if (!(await read($, enabled)) || options.band === 'off') return below
    const r = await read($, reading)
    if (e.props.hasSurvey || r === null || r.window <= 0) return below
    const { Box, Button, Text } = $.ui.resolve(e)
    const t = await ttlFor($, options.cacheTtl)
    // While a turn runs, each of its requests resets the timer, so the countdown only means something between
    // turns: then it runs from the last request.
    const idle = cacheView((await read($, cache)).lastAt, await read($, now), t.ttl, t.why, r.tokens)
    const view = e.props.isWorking
      ? { state: 'warm' as const, left: 1, text: `cache ▸ kept warm while Claude works: each request resets the ${t.ttl} timer` }
      : idle
    const width = Math.max(10, Math.min(60, e.props.bodyColumns - 2))
    const head = [
      `context ▸ ${r.used !== null ? tokens(r.used) : '?'} of ${tokens(r.window)}`,
      r.percent !== null ? `${r.percent}%` : null,
      r.compactsAt === null
        ? 'auto-compact off'
        : `compacts at ${tokens(r.compactsAt)}${r.compactsWhy !== null ? ` (${r.compactsWhy})` : ''}`,
    ].filter(Boolean).join(' · ')
    const columns = Math.max(20, e.props.bodyColumns - 2)
    const rows = legend(r, columns)
    // The whole band when there is room, else the two rows that matter: the fill and the cache clock.
    const isFull = e.props.maxRows >= 6 + rows.length
    const said = await read($, notice)
    // Nothing to compact before the live window's first response (a new or just-compacted conversation),
    // and a compaction is refused while a turn runs: the button shows only when one can work.
    const canCompact = !e.props.isWorking && r.tokens !== null && said?.startsWith('compacting') !== true
    return (
      <Box flexDirection="column">
        <Box justifyContent="space-between" width={columns}>
          <Text wrap="truncate">{`${head} `}</Text>
          {canCompact && <Button key="compact" label="Compact" hotkey="c" onPress={() => compactNow($, detail, e.surface)} />}
        </Box>
        {isFull && (
          <Box>
            {bar(r, width).map((run, i) => (
              <Text key={`run-${i}`} color={run.color ?? undefined} dimColor={run.color === null}>
                {(run.color === null ? '░' : '█').repeat(run.cells)}
              </Text>
            ))}
          </Box>
        )}
        {isFull &&
          rows.map((row, i) => (
            <Box key={`legend-${i}`}>
              {row.map((item, k) => (
                <Box key={item.name}>
                  <Text color={item.color ?? undefined} dimColor={item.color === null}>{`${k > 0 ? '   ' : ''}■ `}</Text>
                  <Text>{`${item.name} `}</Text>
                  <Text bold>{item.tokens}</Text>
                  <Text dimColor>{` ${item.share}`}</Text>
                </Box>
              ))}
            </Box>
          ))}
        <Text wrap="truncate" color={view.state === 'warm' ? fade(view.left) : view.state === 'expired' ? 'error' : undefined} dimColor={view.state === 'none'}>
          {view.text}
        </Text>
        {said !== null && <Text color={said.startsWith('compacting') ? 'warning' : 'error'} wrap="truncate">{`context-meter: ${said}`}</Text>}
        {below}
      </Box>
    )
  })

Licence text (MIT)

MIT License

Copyright (c) 2026 Chien Vu Minh

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

How to build this: Band above the prompt, Add a slash command

What its code calls

env varsrememberscalls tools

What its code shows

Read from the source at commit fdcc3e57ec32. The first group decides whether a mod is listed; the rest is for you to weigh. A later commit is not read until the next crawl.

Decides the listing: code you can check
Entry read	Every module hooks/hooks.json names was read.plugins/context-meter/hooks/register.tsx
Parses	Every file parses as TypeScript or JavaScript.3 files parsed
All its code is in the mod	Every import is a file of the mod or the engine's own module; no packages, no require.all its code is in the mod
Readable	No minified lines, no eval or new Function, no import of a computed path, no encoded blobs.no minified code, no eval, no encoded blobs
Calls in the open	Network and programs are reached as $.http.fetch and $.process.run in place, never passed around.every call outside goes through $ in the open
For you to weigh before installing
Where it draws	The terminal, the desktop app, both, or nothing (hooks only: a guard or a prompt rewriter), as its code says. Shown, never a reason to leave a mod out.draws in the terminal and the desktop app, the same in both
Install line	Whether its repository's own .claude-plugin/marketplace.json lists it, so it installs from that marketplace with the lines on its page.listed in its repository's .claude-plugin/marketplace.json: installs from there
Programs on Windows	Whether every program it starts through $.process exists on Windows (tail, date, open, osascript, /usr/… do not).runs no program a Windows PC lacks
Network	Whether every fetch names its https host in the code.no network
Programs	Whether every program it starts is named in the code and is not a shell, an interpreter or a network tool.starts no programs
Reads and sends	Whether it both reads something of yours (files, environment variables, the transcript, settings) and reaches outside (the network, an MCP server, another session, telemetry).reads environment variables, but reaches nothing outside
Keys in the source	Whether the source holds what looks like an API key or a private key.no keys in the source
Licence	An open licence (MIT, Apache-2.0, BSD, ISC, Unlicense, 0BSD, CC0) with its text lets ModsCode show its code; otherwise the code is linked.MIT
Settings hooks	Hooks declared in hooks/hooks.json or plugin.json beside the module: a command (a shell when it has no args), an HTTP request, an MCP tool or a model prompt at an event. They run outside $.no settings hooks: its function hooks alone
Servers it ships	MCP servers (a program, or a URL; a headersHelper is a shell command; a .mcpb bundle is unpacked at run time), LSP servers, monitors (a shell command for the whole session) and bin/ (on the PATH of the Bash tool).ships no MCP or LSP server, no monitor, no bin/
Skills, commands, agents	What its Markdown declares beyond text: allowed-tools granted for the turn, hooks added when a skill is invoked, a command run before Claude reads the skill.no skills, commands, agents or workflows
Tools and MCP	Whether every tool it calls through $.tool.call and $.mcp.call is named in the code, and none is a shell (Bash through the tool runs a shell without $.process).command.run: /compact
Asks of the model	Completions it runs ($.model.complete, fork, classify), subagents it spawns, prompts it submits as you, and the tools, commands and agents it adds.asks nothing of the model
Events it hooks	By what a hook there can do: gates (refuse a tool call, a prompt, a setting, another plugin), shapes (what the model reads: the system prompt, tool descriptions, each request), reads (your input, the events of the settings hooks, every event with *), and the rest.gates: command.run (context-meter) · shapes: turn.step · also: session.start, session.measure, turn.complete, session.compact (+1) · timers: clock.after, clock.every
Reads, by name	The environment variables and files it names, and whether it reads the transcript, settings.json, the prompt box or the mouse selection.env: CLAUDE_AUTOCOMPACT_PCT_OVERRI…
Writes, by name	The files and environment variables it names, and whether it changes settings, the prompt box, the clipboard, the conversation (a row the model reads) or another session.writes no files, environment variables, settings or conversation rows

This is a reading of the code text, not a security review: it does not run the mod, and it cannot see what a program the mod starts does. The check before installing is yours. How mods are chosen

Install it

Check it yourself before you install it. Mods run unsandboxed, with your permissions, and ModsCode does not vouch for what this code does. Read its code (or run claude plugin validate . in its folder), weigh what it reaches, and install the commit you read.

From its marketplace

Its repository is its marketplace. Add that marketplace (in the terminal with these commands, or in the desktop app's plugin settings) and install the mod from it:

/plugin marketplace add vumichien/claude-code-mods-kit

/plugin install context-meter@chien-mods

/reload-plugins

This installs the marketplace's latest commit, which may not be the one read here (fdcc3e57ec32). Compare them before you install. /reload-plugins loads it into a session that is already open.

Try the commit ModsCode read

No marketplace needed. In a terminal, clone the repository, check out the commit read, validate the mod, and load it for one session:

git clone https://github.com/vumichien/claude-code-mods-kit

git -C claude-code-mods-kit checkout fdcc3e57ec32b6c567ee0032fa8797b1f8b934df

claude plugin validate claude-code-mods-kit/plugins/context-meter

claude --plugin-dir claude-code-mods-kit/plugins/context-meter

The validate line lists the events the mod hooks and what it asks Claude Code to do, without running it. The last line loads the mod for this session only and writes nothing to your settings. If the author has rewritten history, the commit may no longer exist.

Ask Claude about it

With the ModsCode connector added, Claude can read this mod's code and what it reaches, and build on them. Ask it like this:

Read the ModsCode mod "vumichien-context-meter" with its code and make me one like it

Search them from Claude: the MCP connector

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README.md

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