sessions: fold subagent runs into PR attribution

app/renderer/lib/types.ts

@@ -245,6 +245,9 @@ export type MenubarPayload = {
       }>
       distinctCost: number
       distinctSessions: number
+      // Count of subagent (sidechain) runs folded into the PR-linked parent
+      // sessions. Optional (absent when none folded, or from an older producer).
+      subagentSessions?: number
       attributedCost?: number
       unattributedCost?: number
       otherPrCount?: number

app/renderer/sections/PullRequests.test.tsx

@@ -185,6 +185,23 @@ describe('PullRequests', () => {
     expect(screen.getByText(/Not tied to a specific PR/).textContent).toContain('$45.30')
   })
 
+  it('notes folded-in subagent runs in the footer when present', async () => {
+    getOverview.mockResolvedValue(makePayload({ ...SAMPLE, subagentSessions: 32 }))
+    render(<PullRequests period="lifetime" provider="all" />)
+
+    const note = await screen.findByText(/attributed to the rows above/)
+    expect(note.textContent).toContain('3 PR-linked sessions')
+    expect(note.textContent).toContain('32 folded-in subagent runs')
+  })
+
+  it('omits the subagent note when none were folded', async () => {
+    getOverview.mockResolvedValue(makePayload(SAMPLE))
+    render(<PullRequests period="lifetime" provider="all" />)
+
+    const note = await screen.findByText(/attributed to the rows above/)
+    expect(note.textContent).not.toContain('subagent')
+  })
+
   it('marks an approximate (legacy) row with a ~ prefix and a tooltip', async () => {
     const approxPayload: PrPayload = {
       rows: [

app/renderer/sections/PullRequests.tsx

@@ -83,7 +83,7 @@ function PullRequestsPage({ pullRequests, staleError }: { pullRequests?: PullReq
 }
 
 function PrTable({ pullRequests }: { pullRequests: PullRequests }) {
-  const { rows, distinctCost, distinctSessions, attributedCost, unattributedCost, otherPrCount, otherPrCost } = pullRequests
+  const { rows, distinctCost, distinctSessions, subagentSessions, attributedCost, unattributedCost, otherPrCount, otherPrCost } = pullRequests
   const [expandedUrl, setExpandedUrl] = useState<string | null>(null)
   // Reset any open expansion when the PR set changes (a period/provider switch or
   // a refresh that alters the list): a stale expandedUrl would otherwise linger
@@ -145,7 +145,8 @@ function PrTable({ pullRequests }: { pullRequests: PullRequests }) {
       </div>
       {summable ? (
         <p className="pr-footnote">
-          {formatUsd(displayedAttributed)} attributed to the rows above, across {distinctSessions.toLocaleString('en-US')} PR-linked {sessionWord(distinctSessions)}.
+          {formatUsd(displayedAttributed)} attributed to the rows above, across {distinctSessions.toLocaleString('en-US')} PR-linked {sessionWord(distinctSessions)}
+          {subagentSessions ? ` + ${subagentSessions.toLocaleString('en-US')} folded-in subagent ${subagentSessions === 1 ? 'run' : 'runs'}` : ''}.
           {' '}Each turn's cost goes to the PR it was working on, so the rows are summable.
         </p>
       ) : (

src/main.ts

@@ -2011,7 +2011,7 @@ program
   .action(async (opts) => {
     assertProvider(opts.provider, 'sessions')
     assertFormat(opts.format, ['table', 'json'], 'sessions')
-    const { aggregateSessions, aggregateByPr, prLinkedTotals, renderJson, renderTable } = await import('./sessions-report.js')
+    const { aggregateSessions, buildPrAttribution, renderJson, renderTable } = await import('./sessions-report.js')
     await loadPricing()
 
     let range
@@ -2028,16 +2028,16 @@ program
 
     const projects = await parseAllSessions(range, opts.provider)
     if (opts.byPr) {
-      const prRows = aggregateByPr(projects)
+      const { rows: prRows, totals } = buildPrAttribution(projects)
       if (opts.format === 'json') {
-        process.stdout.write(JSON.stringify({ prs: prRows, distinct: prLinkedTotals(projects) }, null, 2) + '\n')
+        process.stdout.write(JSON.stringify({ prs: prRows, distinct: totals }, null, 2) + '\n')
         return
       }
       if (prRows.length === 0) {
         process.stdout.write('No sessions with captured PR links in this period. Links are captured as sessions are parsed; older transcripts gain them on their next re-parse.\n')
         return
       }
-      const { unattributedCost, sessions } = prLinkedTotals(projects)
+      const { unattributedCost, sessions, subagentSessions } = totals
       const { renderTable: renderTextTable } = await import('./text-table.js')
       const modelsCell = (models: string[]): string =>
         models.length === 0 ? '' : models.slice(0, 2).join(', ') + (models.length > 2 ? ` +${models.length - 2}` : '')
@@ -2069,7 +2069,10 @@ program
       const approxNote = prRows.some(r => r.approx)
         ? ' ~ marks rows estimated from a whole-session even split (transcript expired before per-turn capture).'
         : ''
-      process.stdout.write(table + `\nRows sum to $${shownAttributed.toFixed(2)} attributed across ${sessions} PR-linked session${sessions === 1 ? '' : 's'}. $${unattributedCost.toFixed(2)} of that spend was not tied to a specific PR.${approxNote}\n`)
+      const subagentNote = subagentSessions > 0
+        ? ` + ${subagentSessions} folded-in subagent run${subagentSessions === 1 ? '' : 's'}`
+        : ''
+      process.stdout.write(table + `\nRows sum to $${shownAttributed.toFixed(2)} attributed across ${sessions} PR-linked session${sessions === 1 ? '' : 's'}${subagentNote}. $${unattributedCost.toFixed(2)} of that spend was not tied to a specific PR.${approxNote}\n`)
       return
     }
     const rows = aggregateSessions(projects)

src/menubar-json.ts

@@ -57,10 +57,16 @@ export type PeriodData = {
 export type PullRequestsPayload = {
   /// Per-PR rows, cost-descending, capped at the top 20 by the producer.
   rows: PrRow[]
-  /// Distinct-session spend across every PR-linked session. Equals
-  /// `attributedCost + unattributedCost`; kept for backward compatibility.
+  /// PR-linked spend, now INCLUDING the subagent runs folded into those sessions
+  /// (so it can exceed the parents' own spend). Equals `attributedCost +
+  /// unattributedCost`; kept for backward compatibility.
   distinctCost: number
+  /// Count of distinct PR-linked PARENT sessions.
   distinctSessions: number
+  /// Count of subagent (sidechain) runs whose spend was folded into those parent
+  /// sessions. Each remains a standalone row in the sessions list; here it only
+  /// explains why the totals exceed the parents' own spend. 0 when none folded.
+  subagentSessions?: number
   /// Sum of EVERY PR's attributed cost (all rows, not just the sent top 20).
   attributedCost: number
   /// PR-linked spend not tied to any specific PR (pre-reference session