fix(cli): clear delivered image-only queue entries

The queue-removal branch in _handleAgentEvent was gated on the user message
having text, so an image-only steer or follow-up — a pasted screenshot sent
mid-turn — was never spliced out after delivery: pendingMessageCount stayed
above zero and the entry lingered in the queue.

The queues already store "" for such messages, so matching on the empty text
like any other message is enough.

Ported from upstream pi.

Author: Raghav1428

.changeset/image-only-queue-entries.md

@@ -0,0 +1,7 @@
+---
+"@knightcodeai/cli": patch
+---
+
+Clear a delivered steering or follow-up message that carried only images. The
+entry previously stayed in the queue forever, leaving the pending count wrong
+and the message re-queued.

packages/cli/src/core/agent-session.ts

@@ -626,19 +626,17 @@ export class AgentSession {
 		if (event.type === "message_start" && event.message.role === "user") {
 			this._overflowRecoveryAttempted = false;
 			const messageText = contentText(event.message.content, "");
-			if (messageText) {
-				// Check steering queue first
-				const steeringIndex = this._steeringMessages.indexOf(messageText);
-				if (steeringIndex !== -1) {
-					this._steeringMessages.splice(steeringIndex, 1);
+			// Check steering queue first
+			const steeringIndex = this._steeringMessages.indexOf(messageText);
+			if (steeringIndex !== -1) {
+				this._steeringMessages.splice(steeringIndex, 1);
+				this._emitQueueUpdate();
+			} else {
+				// Check follow-up queue
+				const followUpIndex = this._followUpMessages.indexOf(messageText);
+				if (followUpIndex !== -1) {
+					this._followUpMessages.splice(followUpIndex, 1);
 					this._emitQueueUpdate();
-				} else {
-					// Check follow-up queue
-					const followUpIndex = this._followUpMessages.indexOf(messageText);
-					if (followUpIndex !== -1) {
-						this._followUpMessages.splice(followUpIndex, 1);
-						this._emitQueueUpdate();
-					}
 				}
 			}
 		}

packages/cli/test/suite/regressions/8581-image-only-queue-entry.test.ts

@@ -0,0 +1,68 @@
+import type { AgentTool } from "@knightcode/agent";
+import { fauxAssistantMessage, fauxToolCall } from "@knightcode/ai";
+import { Type } from "typebox";
+import { afterEach, describe, expect, it } from "vitest";
+import { createHarness, type Harness } from "../harness.ts";
+
+describe("issue #8581 image-only queue entry", () => {
+	const harnesses: Harness[] = [];
+
+	afterEach(() => {
+		while (harnesses.length > 0) {
+			harnesses.pop()?.cleanup();
+		}
+	});
+
+	it("removes an image-only steering message from the queue after delivery", async () => {
+		let releaseToolExecution: (() => void) | undefined;
+		const toolRelease = new Promise<void>((resolve) => {
+			releaseToolExecution = resolve;
+		});
+		const waitTool: AgentTool = {
+			name: "wait",
+			label: "Wait",
+			description: "Wait for release",
+			parameters: Type.Object({}),
+			execute: async () => {
+				await toolRelease;
+				return { content: [{ type: "text", text: "released" }], details: {} };
+			},
+		};
+
+		const harness = await createHarness({ tools: [waitTool] });
+		harnesses.push(harness);
+
+		const waitForToolStart = new Promise<void>((resolve) => {
+			const unsubscribe = harness.session.subscribe((event) => {
+				if (event.type === "tool_execution_start" && event.toolName === "wait") {
+					unsubscribe();
+					resolve();
+				}
+			});
+		});
+
+		let sawImage = false;
+		harness.setResponses([
+			fauxAssistantMessage(fauxToolCall("wait", {}), { stopReason: "toolUse" }),
+			(context) => {
+				const user = [...context.messages].reverse().find((message) => message.role === "user");
+				sawImage =
+					user?.role === "user" &&
+					typeof user.content !== "string" &&
+					user.content.some((part) => part.type === "image");
+				return fauxAssistantMessage("done");
+			},
+		]);
+
+		const promptPromise = harness.session.prompt("start");
+		await waitForToolStart;
+		await harness.session.steer("", [{ type: "image", mimeType: "image/png", data: "ZmFrZQ==" }]);
+		expect(harness.session.pendingMessageCount).toBe(1);
+		releaseToolExecution?.();
+		await promptPromise;
+
+		expect(sawImage).toBe(true);
+		expect(harness.session.agent.hasQueuedMessages()).toBe(false);
+		expect(harness.session.pendingMessageCount).toBe(0);
+	});
+});