fix(web): only show Codex Fast badge for effective fast tier (#1007)

web/src/components/AssistantChat/StatusBar.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, it } from 'vitest'
-import { shouldShowComposerStatusBar } from './StatusBar'
+import { shouldShowCodexFastBadge, shouldShowComposerStatusBar } from './StatusBar'
 
 describe('shouldShowComposerStatusBar', () => {
     it('hides the composer status bar for Cursor sessions', () => {
@@ -12,3 +12,13 @@ describe('shouldShowComposerStatusBar', () => {
         expect(shouldShowComposerStatusBar(null)).toBe(true)
     })
 })
+
+describe('shouldShowCodexFastBadge', () => {
+    it('uses only the effective service tier', () => {
+        expect(shouldShowCodexFastBadge('codex', undefined)).toBe(false)
+        expect(shouldShowCodexFastBadge('codex', 'standard')).toBe(false)
+        expect(shouldShowCodexFastBadge('codex', 'fast')).toBe(true)
+        expect(shouldShowCodexFastBadge('codex', 'priority')).toBe(true)
+        expect(shouldShowCodexFastBadge('claude', 'fast')).toBe(false)
+    })
+})

web/src/components/AssistantChat/StatusBar.tsx

@@ -125,14 +125,11 @@ function formatTokenCount(value: number): string {
     return String(value)
 }
 
-function isCodexFastMode(model?: string | null, effort?: string | null): boolean {
-    const normalizedEffort = effort?.trim().toLowerCase()
-    if (normalizedEffort === 'none' || normalizedEffort === 'minimal' || normalizedEffort === 'low') {
-        return true
-    }
-
-    const normalizedModel = model?.trim().toLowerCase() ?? ''
-    return normalizedModel.includes('mini') || normalizedModel.includes('fast')
+export function shouldShowCodexFastBadge(
+    agentFlavor: string | null | undefined,
+    serviceTier: string | null | undefined
+): boolean {
+    return agentFlavor === 'codex' && isFastServiceTier(serviceTier)
 }
 
 /** Cursor native ACP does not emit usage_update; hide the bar to avoid empty/misleading UI. */
@@ -210,13 +207,7 @@ export function StatusBar(props: {
     const codexReasoningLabel = shouldShowCodexReasoningLabel(props.agentFlavor)
         ? formatCodexReasoningLabel(props.modelReasoningEffort)
         : null
-    // Prefer the explicit service tier (the real Fast-mode toggle) when set;
-    // fall back to the effort/model heuristic only when the tier is unknown.
-    const codexFastMode = props.agentFlavor === 'codex'
-        ? (props.serviceTier != null
-            ? isFastServiceTier(props.serviceTier)
-            : isCodexFastMode(props.model, props.modelReasoningEffort))
-        : false
+    const codexFastMode = shouldShowCodexFastBadge(props.agentFlavor, props.serviceTier)
     const goalLabel = props.agentFlavor === 'codex' && props.threadGoal
         ? props.threadGoal.status === 'active'
             ? 'goal'