cache-inspector
Track API cache reads, writes, and uncached input by request.
newpanecommand
Track API cache reads, writes, and uncached input by request.
Track API cache reads, writes, and uncached input by request.
Use it when: Check whether repeated turns are using the prompt cache.
Screenshot of this mod's render tree in the fixture preview, with sample data. This is not a capture of the Claude Code application. How previews are made.
claude plugin marketplace add whyashthakker/awesome-claude-code-mods
claude plugin install cache-inspector@awesome-claude-code-modsRun /reload-plugins in an existing session, then /cache-inspector. Use Tab and Enter to operate controls; Esc closes the pane. Terminal and Desktop Code tab supported; pane UI is unavailable in claude -p and the VS Code chat panel.
Try the source without installing:
claude --plugin-dir ./mods/cache-inspectorObserves request token counts and model names in memory. No model calls.
Module variables reset on hot reload. Diagnostic history begins when the mod loads and lasts until reload or process exit; it does not reconstruct earlier activity. All display output is bounded; viewers may truncate long content to 9,000 characters. Relative file paths and Git commands use the session working directory.
Tested with Claude Code 2.1.288. Minimum documented mods version: 2.1.287. The API can change; validate against your installed version.
claude plugin validate mods/cache-inspector --strict
claude plugin test mods/cache-inspectorTests cover plugin commands, pane isolation, both UI surfaces, and the behavior described in tests/register.test.ts. Drawing tests validate element trees; they do not verify pixels painted by the native apps. Validation details.
MIT licensed. No runtime packages or build step required.
hooks/register.js 44 lines1import { clean, text, code, row, frame, bar, pretty, bounded, entries, safePath } from './ui.js'
2const ID = "cache-inspector"
3let records = []
4export function register(on) {
5 on('session.start', async ($, e, next) => {
6
7 await $.command.register({name:ID, description:"Track API cache reads, writes, and uncached input by request.", immediate:true, argumentHint:""})
8 return next(e)
9 })
10 on('command.run', {command:"cache-inspector"}, async ($, e) => {
11
12 await $.ui.open({id:ID,title:"Cache Inspector",focus:true,closeOnEscape:true})
13 return {}
14 })
15
16on('turn.step', async function* ($, e, next) {
17 const result = yield* next(e)
18 if(result.usage) {
19 records = [...records, {model:e.model, agent:e.agentId || 'main', ...result.usage}].slice(-30)
20 $.ui.invalidate('ui.render')
21 }
22 return result
23})
24
25 on('ui.render', {component:'Pane'}, async ($, e, next) => {
26 if(e.requestId !== ID) return next(e)
27 const E = $.ui.resolve(e)
28 try {
29 const body = await draw($, E)
30 return frame(E,"Cache Inspector","Track API cache reads, writes, and uncached input by request.",body)
31 } catch(error) {
32 return frame(E,"Cache Inspector",'Unable to inspect this data.',[text(E,error.message,{color:'yellow'}),E.Button({key:'refresh',label:'Refresh',onPress:()=>$.ui.invalidate('ui.render')})])
33 }
34 })
35}
36async function draw($, E) {
37 const refresh = E.Button({key:'refresh',label:'Refresh',hotkey:'r',plain:true,onPress:()=>$.ui.invalidate('ui.render')})
38
39return [text(E,'Latest 30 completed requests; counts from API reports.'),
40 ...records.map((r,i)=>text(E,(i+1)+'. '+r.agent+' · '+r.model+'\nRead '+(r.cache_read_input_tokens||0)+' · wrote '+(r.cache_creation_input_tokens||0)+' · uncached '+(r.input_tokens||0))),
41 ...(records.length ? [] : [text(E,'No completed requests observed yet.')]), refresh]
42
43}
44hooks/ui.js 36 lines1// Pure UI helpers. No engine access; each plugin contains its own copy.
2export function clean(value, limit = 9000) {
3 return String(value ?? '').replace(/[\u0000-\u0008\u000b\u000c\u000e-\u001f\u007f-\u009f]/g, '').slice(0, limit)
4}
5export function text(E, value, props = {}) {
6 return E.Text({ ...props, children: [clean(value)] })
7}
8export function code(E, value, language = 'text') {
9 return E.Code({ source: clean(value), language })
10}
11export function row(E, children) {
12 return E.Box({ flexDirection: 'row', columnGap: 2, flexWrap: 'wrap', children })
13}
14export function frame(E, title, subtitle, children) {
15 return E.Box({ flexDirection: 'column', gap: 1, children: [
16 text(E, title, { bold: true, color: 'cyan' }),
17 text(E, subtitle, { dimColor: true }), ...children,
18 ] })
19}
20export function bar(percent, width = 24) {
21 const p = Math.max(0, Math.min(100, Number(percent) || 0))
22 const n = Math.round(p / 100 * width)
23 return '[' + '#'.repeat(n) + '-'.repeat(width - n) + '] ' + p.toFixed(1) + '%'
24}
25export function pretty(value) { return JSON.stringify(value, null, 2) }
26export function bounded(value, max = 9000) {
27 if (value.length > max) throw new Error('Input exceeds ' + max + ' characters. Use a smaller selection.')
28 return value
29}
30export function entries(value) { return value && typeof value === 'object' ? Object.entries(value) : [] }
31export function safePath(value) {
32 const path = value.trim()
33 if (!path || path.startsWith('-') || /[\x00-\x1f]/.test(path)) throw new Error('Enter a path without control characters or leading flags.')
34 return path
35}
36