fix(ai): show implied Kimi Coding subscription costs

packages/coding-agent/CHANGELOG.md

@@ -5,6 +5,7 @@
 ### Fixed
 
 - Fixed obsolete custom UI, custom tool, and custom editor examples in the extension documentation ([#6735](https://github.com/earendil-works/pi/issues/6735)).
+- Fixed Kimi Coding sessions to show API-equivalent implied costs with the subscription indicator.
 
 ## [0.80.10] - 2026-07-16
 

packages/coding-agent/src/modes/interactive/components/footer.ts

@@ -137,8 +137,10 @@ export class FooterComponent implements Component {
 		if ((totalCacheRead > 0 || totalCacheWrite > 0) && latestCacheHitRate !== undefined) {
 			statsParts.push(`CH${latestCacheHitRate.toFixed(1)}%`);
 		}
-		// Show cost with "(sub)" indicator if using OAuth subscription
-		const usingSubscription = state.model ? this.session.modelRuntime.isUsingOAuth(state.model.provider) : false;
+		// Kimi Coding is subscription-backed despite using API-key authentication.
+		const usingSubscription = state.model
+			? state.model.provider === "kimi-coding" || this.session.modelRuntime.isUsingOAuth(state.model.provider)
+			: false;
 		if (totalCost || usingSubscription) {
 			const costStr = `$${totalCost.toFixed(3)}${usingSubscription ? " (sub)" : ""}`;
 			statsParts.push(costStr);

packages/coding-agent/test/footer-width.test.ts

@@ -141,4 +141,21 @@ describe("FooterComponent width handling", () => {
 		const statsLine = stripAnsi(footer.render(120)[1]);
 		expect(statsLine).toContain("CH25.0%");
 	});
+
+	it("marks Kimi Coding costs as subscription estimates", () => {
+		const session = createSession({
+			sessionName: "",
+			provider: "kimi-coding",
+			usage: {
+				input: 100,
+				output: 10,
+				cacheRead: 0,
+				cacheWrite: 0,
+				cost: { total: 1.234 },
+			},
+		});
+		const footer = new FooterComponent(session, createFooterData(1));
+
+		expect(stripAnsi(footer.render(120)[1])).toContain("$1.234 (sub)");
+	});
 });