diff --git a/packages/coding-agent/CHANGELOG.md b/packages/coding-agent/CHANGELOG.md
index 0ac6a6c0e..415a1be94 100644
--- a/packages/coding-agent/CHANGELOG.md
+++ b/packages/coding-agent/CHANGELOG.md
@@ -2,6 +2,10 @@
## [Unreleased]
+### Fixed
+
+- Pending resolve reminders now trigger as soon as a preview action is queued, before the next assistant turn, with regression coverage in `agent-session-resolve-reminder` tests
+
## [13.4.0] - 2026-03-01
### Breaking Changes
diff --git a/packages/coding-agent/src/session/agent-session.ts b/packages/coding-agent/src/session/agent-session.ts
index 8450c2751..afc80bde4 100644
--- a/packages/coding-agent/src/session/agent-session.ts
+++ b/packages/coding-agent/src/session/agent-session.ts
@@ -291,6 +291,7 @@ export class AgentSession {
// Event subscription state
#unsubscribeAgent?: () => void;
+ #unsubscribePendingActionPush?: () => void;
#eventListeners: AgentSessionEventListener[] = [];
/** Tracks pending steering messages for UI display. Removed when delivered. */
@@ -397,6 +398,21 @@ export class AgentSession {
this.#obfuscator = config.obfuscator;
this.agent.providerSessionState = this.#providerSessionState;
this.#pendingActionStore = config.pendingActionStore;
+ this.#unsubscribePendingActionPush = this.#pendingActionStore?.subscribePush(action => {
+ const reminderText = [
+ "",
+ "This is a preview. Call the `resolve` tool to apply or discard these changes.",
+ "",
+ ].join("\n");
+ this.agent.steer({
+ role: "custom",
+ customType: "resolve-reminder",
+ content: reminderText,
+ display: false,
+ details: { toolName: action.sourceToolName },
+ timestamp: Date.now(),
+ });
+ });
this.#syncTodoPhasesFromBranch();
// Always subscribe to agent events for internal handling
@@ -688,22 +704,6 @@ export class AgentSession {
{ deliverAs: "nextTurn" },
);
}
- if (!isError && this.#pendingActionStore?.hasPending) {
- const reminderText = [
- "",
- "This is a preview. Call the `resolve` tool to apply or discard these changes.",
- "",
- ].join("\n");
- await this.sendCustomMessage(
- {
- customType: "resolve-reminder",
- content: reminderText,
- display: false,
- details: { toolName },
- },
- { deliverAs: "nextTurn" },
- );
- }
}
}
@@ -1443,6 +1443,8 @@ export class AgentSession {
state.close();
}
this.#providerSessionState.clear();
+ this.#unsubscribePendingActionPush?.();
+ this.#unsubscribePendingActionPush = undefined;
this.#disconnectFromAgent();
this.#eventListeners = [];
}
diff --git a/packages/coding-agent/src/tools/pending-action.ts b/packages/coding-agent/src/tools/pending-action.ts
index 315edba7f..71446eca0 100644
--- a/packages/coding-agent/src/tools/pending-action.ts
+++ b/packages/coding-agent/src/tools/pending-action.ts
@@ -10,9 +10,14 @@ export interface PendingAction {
export class PendingActionStore {
#actions: PendingAction[] = [];
+ #pushListeners = new Set<(action: PendingAction, count: number) => void>();
push(action: PendingAction): void {
this.#actions.push(action);
+ const count = this.#actions.length;
+ for (const listener of this.#pushListeners) {
+ listener(action, count);
+ }
}
peek(): PendingAction | null {
@@ -23,10 +28,21 @@ export class PendingActionStore {
return this.#actions.pop() ?? null;
}
+ subscribePush(listener: (action: PendingAction, count: number) => void): () => void {
+ this.#pushListeners.add(listener);
+ return () => {
+ this.#pushListeners.delete(listener);
+ };
+ }
+
clear(): void {
this.#actions = [];
}
+ get count(): number {
+ return this.#actions.length;
+ }
+
get hasPending(): boolean {
return this.#actions.length > 0;
}
diff --git a/packages/coding-agent/test/agent-session-resolve-reminder.test.ts b/packages/coding-agent/test/agent-session-resolve-reminder.test.ts
new file mode 100644
index 000000000..8f635c044
--- /dev/null
+++ b/packages/coding-agent/test/agent-session-resolve-reminder.test.ts
@@ -0,0 +1,118 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from "bun:test";
+import * as fs from "node:fs";
+import * as os from "node:os";
+import * as path from "node:path";
+import { Agent } from "@oh-my-pi/pi-agent-core";
+import { type AssistantMessage, getBundledModel } from "@oh-my-pi/pi-ai";
+import { AssistantMessageEventStream } from "@oh-my-pi/pi-ai/utils/event-stream";
+import { ModelRegistry } from "@oh-my-pi/pi-coding-agent/config/model-registry";
+import { Settings } from "@oh-my-pi/pi-coding-agent/config/settings";
+import { AgentSession } from "@oh-my-pi/pi-coding-agent/session/agent-session";
+import { AuthStorage } from "@oh-my-pi/pi-coding-agent/session/auth-storage";
+import { SessionManager } from "@oh-my-pi/pi-coding-agent/session/session-manager";
+import { PendingActionStore } from "@oh-my-pi/pi-coding-agent/tools/pending-action";
+import { Snowflake } from "@oh-my-pi/pi-utils";
+
+class MockAssistantStream extends AssistantMessageEventStream {}
+
+function createAssistantMessage(text: string): AssistantMessage {
+ return {
+ role: "assistant",
+ content: [{ type: "text", text }],
+ api: "anthropic-messages",
+ provider: "anthropic",
+ model: "mock",
+ usage: {
+ input: 0,
+ output: 0,
+ cacheRead: 0,
+ cacheWrite: 0,
+ totalTokens: 0,
+ cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0, total: 0 },
+ },
+ stopReason: "stop",
+ timestamp: Date.now(),
+ };
+}
+
+describe("AgentSession resolve reminder", () => {
+ let session: AgentSession;
+ let tempDir: string;
+ let pendingActionStore: PendingActionStore;
+ let streamCallCount = 0;
+
+ beforeEach(async () => {
+ tempDir = path.join(os.tmpdir(), `pi-resolve-reminder-test-${Snowflake.next()}`);
+ fs.mkdirSync(tempDir, { recursive: true });
+ pendingActionStore = new PendingActionStore();
+ streamCallCount = 0;
+
+ const model = getBundledModel("anthropic", "claude-sonnet-4-5");
+ if (!model) {
+ throw new Error("Test model not found in registry");
+ }
+
+ const authStorage = await AuthStorage.create(path.join(tempDir, "testauth.db"));
+ authStorage.setRuntimeApiKey("anthropic", "test-key");
+ const modelRegistry = new ModelRegistry(authStorage, path.join(tempDir, "models.yml"));
+
+ const agent = new Agent({
+ initialState: {
+ model,
+ systemPrompt: "Test",
+ tools: [],
+ messages: [],
+ },
+ streamFn: () => {
+ streamCallCount += 1;
+ if (streamCallCount === 1) {
+ pendingActionStore.push({
+ label: "AST Edit: 1 replacement in 1 file",
+ sourceToolName: "ast_edit",
+ apply: async () => ({ content: [{ type: "text", text: "Applied" }] }),
+ });
+ }
+ const stream = new MockAssistantStream();
+ queueMicrotask(() => {
+ stream.push({ type: "start", partial: createAssistantMessage("") });
+ stream.push({ type: "done", reason: "stop", message: createAssistantMessage("Done") });
+ });
+ return stream;
+ },
+ });
+
+ session = new AgentSession({
+ agent,
+ sessionManager: SessionManager.inMemory(),
+ settings: Settings.isolated(),
+ modelRegistry,
+ pendingActionStore,
+ });
+ });
+
+ afterEach(async () => {
+ await session.dispose();
+ if (fs.existsSync(tempDir)) {
+ fs.rmSync(tempDir, { recursive: true, force: true });
+ }
+ vi.restoreAllMocks();
+ });
+
+ it("forces an immediate steering turn and injects resolve reminder before second assistant response", async () => {
+ await session.prompt("run preview");
+
+ expect(streamCallCount).toBe(2);
+
+ const messages = session.agent.state.messages;
+ const assistantIndices = messages
+ .map((message, index) => (message.role === "assistant" ? index : -1))
+ .filter(index => index >= 0);
+ const reminderIndex = messages.findIndex(
+ message => message.role === "custom" && message.customType === "resolve-reminder",
+ );
+
+ expect(assistantIndices.length).toBe(2);
+ expect(reminderIndex).toBeGreaterThan(assistantIndices[0]!);
+ expect(reminderIndex).toBeLessThan(assistantIndices[1]!);
+ });
+});