diff --git a/packages/coding-agent/src/session/session-advisors.ts b/packages/coding-agent/src/session/session-advisors.ts
index 8d09bb6f2..4365e2582 100644
--- a/packages/coding-agent/src/session/session-advisors.ts
+++ b/packages/coding-agent/src/session/session-advisors.ts
@@ -1355,6 +1355,8 @@ export class SessionAdvisors {
 		});
 
 		for (const candidate of candidates) {
+			const apiKey = await this.#host.modelRegistry.getApiKey(candidate, advisorProviderSessionId, { signal });
+			if (!apiKey) continue;
 			if (
 				nativeCompactionFailure &&
 				(candidate.provider !== nativeCompactionFailure.provider ||
@@ -1362,8 +1364,7 @@ export class SessionAdvisors {
 			) {
 				throw nativeCompactionFailure.error;
 			}
-			const apiKey = await this.#host.modelRegistry.getApiKey(candidate, advisorProviderSessionId, { signal });
-			if (!apiKey) continue;
+
 			// The advisor overflow-compaction one-shot bypasses the advisor `Agent`,
 			// so its installed metadata resolver never runs. Emit the same
 			// `metadata.user_id` identity here (resolved per candidate provider,
diff --git a/packages/coding-agent/src/session/session-maintenance.ts b/packages/coding-agent/src/session/session-maintenance.ts
index 78c532578..19cd40efa 100644
--- a/packages/coding-agent/src/session/session-maintenance.ts
+++ b/packages/coding-agent/src/session/session-maintenance.ts
@@ -2490,6 +2490,9 @@ export class SessionMaintenance {
 
 				for (let candidateIndex = 0; candidateIndex < candidates.length; candidateIndex++) {
 					const candidate = candidates[candidateIndex];
+					const hasMoreCandidates = candidateIndex < candidates.length - 1;
+					const apiKey = await this.#host.modelRegistry.getApiKey(candidate, this.#host.sessionId());
+					if (!apiKey) continue;
 					if (
 						nativeCompactionFailure &&
 						(candidate.provider !== nativeCompactionFailure.provider ||
@@ -2497,9 +2500,6 @@ export class SessionMaintenance {
 					) {
 						throw nativeCompactionFailure.error;
 					}
-					const hasMoreCandidates = candidateIndex < candidates.length - 1;
-					const apiKey = await this.#host.modelRegistry.getApiKey(candidate, this.#host.sessionId());
-					if (!apiKey) continue;
 
 					let attempt = 0;
 					while (true) {
diff --git a/packages/coding-agent/test/advisor-context-maintenance.test.ts b/packages/coding-agent/test/advisor-context-maintenance.test.ts
index 575579d68..a9755db38 100644
--- a/packages/coding-agent/test/advisor-context-maintenance.test.ts
+++ b/packages/coding-agent/test/advisor-context-maintenance.test.ts
@@ -172,13 +172,13 @@ describe("AgentSession advisor context maintenance", () => {
 		const advisor = session.getAdvisorAgent();
 		if (!advisor) throw new Error("Expected advisor agent to be active");
 		advisor.setModel(nativeModel);
-		vi.spyOn(modelRegistry, "getApiKey").mockResolvedValue("test-key");
+		const apiKeySpy = vi.spyOn(modelRegistry, "getApiKey").mockResolvedValue("test-key");
 		vi.spyOn(modelRegistry, "getAvailable").mockReturnValue([nativeModel, sameProviderModel, crossProviderModel]);
 		advisor.state.messages.push(
 			usageAnchor(advisorMock, Date.now() - 2_000),
 			usageAnchor(advisorMock, Date.now() - 1_000),
 		);
-		return { advisor, crossProviderModel, nativeModel, sameProviderModel };
+		return { advisor, apiKeySpy, crossProviderModel, nativeModel, sameProviderModel, settings };
 	}
 
 	it("maintains a 371,200-token cached advisor context before the 372,000-token window", async () => {
@@ -467,6 +467,38 @@ describe("AgentSession advisor context maintenance", () => {
 		expect(JSON.stringify(advisor.state.messages)).toContain("same-provider native summary");
 	});
 
+	it("skips unauthenticated advisor candidates before enforcing the native boundary", async () => {
+		const { advisor, apiKeySpy, crossProviderModel, nativeModel, sameProviderModel, settings } =
+			createAdvisorFallbackHarness();
+		settings.setModelRole("smol", `${crossProviderModel.provider}/${crossProviderModel.id}`);
+		settings.setModelRole("slow", `${sameProviderModel.provider}/${sameProviderModel.id}`);
+		apiKeySpy.mockImplementation(async model =>
+			model.provider === crossProviderModel.provider && model.id === crossProviderModel.id ? undefined : "test-key",
+		);
+		const compactSpy = vi.spyOn(compactionModule, "compact").mockImplementation(async (preparation, model) => {
+			if (model.provider === nativeModel.provider && model.id === nativeModel.id) {
+				throw new compactionModule.NativeCompactionError(new Error("V2 native compaction transport failed"));
+			}
+			if (model.provider === sameProviderModel.provider && model.id === sameProviderModel.id) {
+				return {
+					summary: "authenticated same-provider advisor summary",
+					shortSummary: "authenticated same-provider advisor",
+					firstKeptEntryId: preparation.firstKeptEntryId,
+					tokensBefore: 42,
+				};
+			}
+			throw new Error(`Unexpected advisor compaction model ${model.provider}/${model.id}`);
+		});
+
+		await session.prompt("small current update");
+
+		expect(compactSpy.mock.calls.map(([, model]) => `${model.provider}/${model.id}`)).toEqual([
+			`${nativeModel.provider}/${nativeModel.id}`,
+			`${sameProviderModel.provider}/${sameProviderModel.id}`,
+		]);
+		expect(JSON.stringify(advisor.state.messages)).toContain("authenticated same-provider advisor summary");
+	});
+
 	it("stops before a same-provider advisor candidate with native compaction disabled", async () => {
 		const { advisor, nativeModel, sameProviderModel } = createAdvisorFallbackHarness({
 			sameProviderNativeEnabled: false,
diff --git a/packages/coding-agent/test/issue-986-compaction-auth-fallback.test.ts b/packages/coding-agent/test/issue-986-compaction-auth-fallback.test.ts
index ace5f61f7..1c8f1c51c 100644
--- a/packages/coding-agent/test/issue-986-compaction-auth-fallback.test.ts
+++ b/packages/coding-agent/test/issue-986-compaction-auth-fallback.test.ts
@@ -130,7 +130,7 @@ describe("issue #986 compaction auth fallback", () => {
 			session.sessionManager.appendMessage(assistant);
 		}
 		vi.spyOn(modelRegistry, "getAvailable").mockReturnValue([currentModel, sameProviderModel, crossProviderModel]);
-		vi.spyOn(modelRegistry, "getApiKey").mockResolvedValue("test-key");
+		const apiKeySpy = vi.spyOn(modelRegistry, "getApiKey").mockResolvedValue("test-key");
 
 		const triggerAutoCompaction = async (): Promise<void> => {
 			const { promise, resolve } = Promise.withResolvers<void>();
@@ -159,7 +159,7 @@ describe("issue #986 compaction auth fallback", () => {
 			await session.waitForIdle();
 		};
 
-		return { crossProviderModel, currentModel, sameProviderModel, triggerAutoCompaction };
+		return { apiKeySpy, crossProviderModel, currentModel, sameProviderModel, triggerAutoCompaction };
 	}
 
 	it("continues same-provider native candidates but stops before crossing providers on non-auth failure", async () => {
@@ -190,6 +190,39 @@ describe("issue #986 compaction auth fallback", () => {
 		]);
 	});
 
+	it("skips unauthenticated cross-provider candidates before enforcing the native boundary", async () => {
+		const { apiKeySpy, crossProviderModel, currentModel, sameProviderModel, triggerAutoCompaction } =
+			await createAutoNativeFallbackSession();
+		session.settings.setModelRole("smol", `${crossProviderModel.provider}/${crossProviderModel.id}`);
+		session.settings.setModelRole("slow", `${sameProviderModel.provider}/${sameProviderModel.id}`);
+		apiKeySpy.mockImplementation(async model =>
+			model.provider === crossProviderModel.provider ? undefined : "test-key",
+		);
+		const attemptedModels: string[] = [];
+		vi.spyOn(compactionModule, "compact").mockImplementation(async (preparation, model) => {
+			attemptedModels.push(`${model.provider}/${model.id}`);
+			if (model.provider === currentModel.provider && model.id === currentModel.id) {
+				throw new compactionModule.NativeCompactionError(new Error("native compaction transport failed"));
+			}
+			if (model.provider === sameProviderModel.provider && model.id === sameProviderModel.id) {
+				return {
+					summary: "authenticated same-provider summary",
+					shortSummary: "authenticated same-provider",
+					firstKeptEntryId: preparation.firstKeptEntryId,
+					tokensBefore: 42,
+				};
+			}
+			throw new Error(`Unexpected compaction model ${model.provider}/${model.id}`);
+		});
+
+		await triggerAutoCompaction();
+
+		expect(attemptedModels).toEqual([
+			`${currentModel.provider}/${currentModel.id}`,
+			`${sameProviderModel.provider}/${sameProviderModel.id}`,
+		]);
+	});
+
 	it("retries a transient native compaction failure on the same candidate", async () => {
 		const { currentModel, triggerAutoCompaction } = await createAutoNativeFallbackSession();
 		session.settings.set("retry.enabled", true);