diff --git a/packages/coding-agent/test/agent-session-snapcompact-budget.test.ts b/packages/coding-agent/test/agent-session-snapcompact-budget.test.ts
index d3f3d257e..d100024c3 100644
--- a/packages/coding-agent/test/agent-session-snapcompact-budget.test.ts
+++ b/packages/coding-agent/test/agent-session-snapcompact-budget.test.ts
@@ -246,6 +246,11 @@ describe("AgentSession snapcompact frame-budget sizing", () => {
 		const model = session.model;
 		if (!model) throw new Error("Expected model");
 		await session.dispose();
+		// dispose() released the manager's in-memory transcript; reopen the
+		// persisted file for the replacement session, as revival paths do.
+		const sessionFile = sessionManager.getSessionFile();
+		if (!sessionFile) throw new Error("Expected a persisted session file");
+		sessionManager = await SessionManager.open(sessionFile, tempDir.path());
 		const unknownWindowModel = { ...model, contextWindow: 0 };
 		session = new AgentSession({
 			agent: new Agent({
diff --git a/packages/coding-agent/test/session-exit-diagnostics.test.ts b/packages/coding-agent/test/session-exit-diagnostics.test.ts
index 466f85526..4718716bf 100644
--- a/packages/coding-agent/test/session-exit-diagnostics.test.ts
+++ b/packages/coding-agent/test/session-exit-diagnostics.test.ts
@@ -67,7 +67,7 @@ describe("session exit diagnostics", () => {
 		const modelRegistry = new ModelRegistry(authStorage);
 		const model = getBundledModel("anthropic", "claude-sonnet-4-5");
 		if (!model) throw new Error("Expected built-in anthropic model to exist");
-		const sessionManager = SessionManager.inMemory(tempDir.path());
+		const sessionManager = SessionManager.create(tempDir.path(), tempDir.path());
 		const agent = new Agent({
 			initialState: {
 				model,
@@ -116,9 +116,15 @@ describe("session exit diagnostics", () => {
 
 		await session.dispose();
 		session = undefined;
-		const exitEntry = sessionManager
+		// dispose() released the in-memory transcript; the exit marker's contract
+		// is durability, so assert against the persisted file.
+		const sessionFile = sessionManager.getSessionFile();
+		if (!sessionFile) throw new Error("Expected a persisted session file");
+		const reopened = await SessionManager.open(sessionFile, tempDir.path());
+		const exitEntry = reopened
 			.getEntries()
 			.find(entry => entry.type === "custom" && entry.customType === SESSION_EXIT_CUSTOM_TYPE);
+		await reopened.close();
 		if (exitEntry?.type !== "custom") throw new Error("Expected session exit marker");
 		expect(exitEntry.data).toMatchObject({
 			reason: "dispose",
@@ -140,7 +146,7 @@ describe("session exit diagnostics", () => {
 		const modelRegistry = new ModelRegistry(authStorage);
 		const model = getBundledModel("anthropic", "claude-sonnet-4-5");
 		if (!model) throw new Error("Expected built-in anthropic model to exist");
-		const sessionManager = SessionManager.inMemory(tempDir.path());
+		const sessionManager = SessionManager.create(tempDir.path(), tempDir.path());
 		const agent = new Agent({
 			initialState: {
 				model,
@@ -187,9 +193,13 @@ describe("session exit diagnostics", () => {
 		await teardown(postmortem.Reason.SIGTERM);
 		session = undefined;
 
-		const exitEntry = sessionManager
+		const sessionFile = sessionManager.getSessionFile();
+		if (!sessionFile) throw new Error("Expected a persisted session file");
+		const reopened = await SessionManager.open(sessionFile, tempDir.path());
+		const exitEntry = reopened
 			.getEntries()
 			.find(entry => entry.type === "custom" && entry.customType === SESSION_EXIT_CUSTOM_TYPE);
+		await reopened.close();
 		if (exitEntry?.type !== "custom") throw new Error("Expected session exit marker");
 		expect(exitEntry.data).toMatchObject({
 			reason: "sigterm",