diff --git a/src/lib/tray-primary-progress.test.ts b/src/lib/tray-primary-progress.test.ts
index f2989a5ba..f233f31b6 100644
--- a/src/lib/tray-primary-progress.test.ts
+++ b/src/lib/tray-primary-progress.test.ts
@@ -302,5 +302,46 @@ describe("getTrayPrimaryBars", () => {
     })
     expect(bars).toEqual([])
   })
+
+  it("falls back to the first progress line when no declared candidate is present", () => {
+    // Usage-based Codex plans report only "Credits", never the declared "Session"
+    // candidate. Without a fallback the tray renders "--%" instead of a real number.
+    const bars = getTrayPrimaryBars({
+      pluginsMeta: [
+        {
+          id: "codex",
+          name: "Codex",
+          iconUrl: "",
+          primaryCandidates: ["Session"],
+          lines: [],
+        },
+      ],
+      pluginSettings: { order: ["codex"], disabled: [] },
+      pluginStates: {
+        codex: {
+          data: {
+            providerId: "codex",
+            displayName: "Codex",
+            iconUrl: "",
+            lines: [
+              {
+                type: "progress",
+                label: "Credits",
+                used: 1000,
+                limit: 1000,
+                format: { kind: "count", suffix: "credits" },
+              },
+            ],
+          },
+          loading: false,
+          error: null,
+        },
+      },
+      displayMode: "left",
+    })
+
+    // 1000 of 1000 used, "left" mode -> 0 remaining -> 0%, not undefined
+    expect(bars).toEqual([{ id: "codex", fraction: 0 }])
+  })
 })
 
diff --git a/src/lib/tray-primary-progress.ts b/src/lib/tray-primary-progress.ts
index a139e29df..6ff0e88d6 100644
--- a/src/lib/tray-primary-progress.ts
+++ b/src/lib/tray-primary-progress.ts
@@ -65,18 +65,21 @@ export function getTrayPrimaryBars(args: {
       const primaryLabel = meta.primaryCandidates.find((label) =>
         data.lines.some((line) => isProgressLine(line) && line.label === label)
       )
-      if (primaryLabel) {
-        const primaryLine = data.lines.find(
-          (line): line is ProgressLine =>
-            isProgressLine(line) && line.label === primaryLabel
-        )
-        if (primaryLine && primaryLine.limit > 0) {
-          const shownAmount =
-            displayMode === "used"
-              ? primaryLine.used
-              : primaryLine.limit - primaryLine.used
-          fraction = clamp01(shownAmount / primaryLine.limit)
-        }
+      // Some plans expose none of the declared candidates (usage-based Codex reports only
+      // "Credits", never "Session"). Fall back to the first progress line so the tray shows
+      // a real number instead of "--%".
+      const primaryLine = primaryLabel
+        ? data.lines.find(
+            (line): line is ProgressLine =>
+              isProgressLine(line) && line.label === primaryLabel
+          )
+        : data.lines.find((line): line is ProgressLine => isProgressLine(line))
+      if (primaryLine && primaryLine.limit > 0) {
+        const shownAmount =
+          displayMode === "used"
+            ? primaryLine.used
+            : primaryLine.limit - primaryLine.used
+        fraction = clamp01(shownAmount / primaryLine.limit)
       }
     }