diff --git a/docs/automode-classifier-flow.md b/docs/automode-classifier-flow.md
index fcbb2fc..e24b31f 100644
--- a/docs/automode-classifier-flow.md
+++ b/docs/automode-classifier-flow.md
@@ -265,11 +265,13 @@ No classifier model/API key available; auto mode fails closed.
 Classifier calls use:
 
 ```text
-temperature: 0
-maxTokens: 700
+maxTokens: 1200
 signal: ctx.signal
 ```
 
+The classifier does not force a temperature, because some providers reject the
+parameter. Provider defaults are used instead.
+
 ## Parsing the classifier result
 
 The parser accepts JSON returned directly, JSON inside a fenced code block, or the first JSON-looking object in the response.
@@ -287,7 +289,7 @@ If parsing fails, the action is blocked with this reason:
 Classifier response was not valid decision JSON; auto mode fails closed.
 ```
 
-If the model call throws, the action is blocked with a classifier failure message.
+If the model call throws or returns a provider error, the action is blocked with a classifier failure message.
 
 ## State, UI, and denial history
 
diff --git a/docs/observability-logging.md b/docs/observability-logging.md
index aed3f59..48e5e8f 100644
--- a/docs/observability-logging.md
+++ b/docs/observability-logging.md
@@ -86,7 +86,7 @@ Written only for classifier-routed actions, and only when `classifierIo: true`.
 
 Each `attempts[]` entry is `{ attempt, response?, parsed?, error?, durationMs }`:
 
-- `response` — `{ stopReason, text, model, timestamp, usage }`, the raw model output and provider-reported usage for that attempt.
+- `response` — `{ stopReason, text, model, timestamp, usage, errorMessage? }`, the raw model output and provider-reported usage for that attempt, including provider-reported errors.
 - `parsed` — the decision parsed from the response, or absent if it did not parse.
 - `error` — present when the call threw (network/auth); `response` is then absent.
 
diff --git a/extensions/auto-mode/classifier.ts b/extensions/auto-mode/classifier.ts
index 4d04889..06cd1b7 100644
--- a/extensions/auto-mode/classifier.ts
+++ b/extensions/auto-mode/classifier.ts
@@ -65,7 +65,7 @@ export type ClassifierCompletionFn = (
     headers?: Record<string, string>;
     signal?: AbortSignal;
     maxTokens: number;
-    temperature: number;
+    temperature?: number;
   },
 ) => Promise<AssistantMessage>;
 
@@ -125,8 +125,8 @@ export function parseClassifierDecision(
  *
  * Safety is preserved: an "allow" is only returned when a response actually
  * parses to a valid allow decision. If every attempt fails to parse, the
- * function fails closed with a block decision. Thrown errors (network/auth)
- * are not retried — they fail closed immediately, matching prior behavior.
+ * function fails closed with a block decision. Thrown or provider-reported
+ * errors are not retried — they fail closed immediately.
  */
 export async function classifyWithRetry(
   completeFn: ClassifierCompletionFn,
@@ -141,7 +141,7 @@ export async function classifyWithRetry(
 ): Promise<ClassificationDecision> {
   const maxAttempts = options.maxAttempts ?? 2;
   const maxTokens = options.maxTokens ?? 1200;
-  const temperature = options.temperature ?? 0;
+  const temperature = options.temperature;
   const onAttempt = options.onAttempt;
   let lastReason =
     "Classifier response was not valid decision JSON; auto mode fails closed.";
@@ -157,7 +157,7 @@ export async function classifyWithRetry(
           headers: classifier.headers,
           signal,
           maxTokens,
-          temperature,
+          ...(temperature === undefined ? {} : { temperature }),
         },
       );
     } catch (error) {
@@ -174,7 +174,10 @@ export async function classifyWithRetry(
       };
     }
     const durationMs = Date.now() - started;
-    const decision = parseClassifierDecision(response);
+    const providerError = response.stopReason === "error";
+    const decision = providerError
+      ? undefined
+      : parseClassifierDecision(response);
     onAttempt?.({
       attempt: attempt + 1,
       response: {
@@ -183,10 +186,22 @@ export async function classifyWithRetry(
         model: response.model,
         timestamp: response.timestamp,
         usage: response.usage,
+        ...(response.errorMessage === undefined
+          ? {}
+          : { errorMessage: response.errorMessage }),
       },
       parsed: decision,
       durationMs,
     });
+    if (providerError) {
+      const errorMessage = response.errorMessage ||
+        "Classifier model returned an error response.";
+      return {
+        decision: "block",
+        tier: "none",
+        reason: `Classifier failed; auto mode fails closed: ${errorMessage}`,
+      };
+    }
     if (decision) return decision;
     lastReason =
       response.stopReason === "length"
diff --git a/extensions/auto-mode/types.ts b/extensions/auto-mode/types.ts
index 1799562..4ed8c2c 100644
--- a/extensions/auto-mode/types.ts
+++ b/extensions/auto-mode/types.ts
@@ -98,6 +98,7 @@ export type ClassifierIoAttempt = {
     model: string;
     timestamp: number;
     usage: AssistantMessage["usage"];
+    errorMessage?: string;
   };
   parsed?: ClassificationDecision;
   error?: string;
diff --git a/tests/auto-mode.test.ts b/tests/auto-mode.test.ts
index 6586949..69af227 100644
--- a/tests/auto-mode.test.ts
+++ b/tests/auto-mode.test.ts
@@ -394,14 +394,14 @@ const VALID_ALLOW = '{"decision":"allow","tier":"allow","reason":"read-only"}';
 const GARBAGE = "and I'm ready to go. I'll start by listing the ability to ability to ability to";
 
 function fakeComplete(responses: AssistantMessage[]) {
-	const calls: Array<{ maxTokens: number; temperature: number }> = [];
+	const calls: Array<{ maxTokens: number; temperature?: number }> = [];
 	let i = 0;
 	const fn = async (
 		_model: unknown,
 		_options: unknown,
-		callOptions: { maxTokens: number; temperature: number },
+		callOptions: { maxTokens: number; temperature?: number },
 	): Promise<AssistantMessage> => {
-		calls.push({ maxTokens: callOptions.maxTokens, temperature: callOptions.temperature });
+		calls.push({ ...callOptions });
 		const res = responses[i];
 		i += 1;
 		return res;
@@ -419,6 +419,21 @@ test("classifyWithRetry returns a valid decision on the first attempt without re
 	);
 	assert.equal(decision.decision, "allow");
 	assert.equal(calls.length, 1);
+	assert.equal(calls[0]?.maxTokens, 1200);
+	assert.equal(Object.hasOwn(calls[0] ?? {}, "temperature"), false);
+});
+
+test("classifyWithRetry forwards an explicitly configured temperature", async () => {
+	const { fn, calls } = fakeComplete([assistantWith(VALID_ALLOW)]);
+	const decision = await classifyWithRetry(
+		fn,
+		{ model: { provider: "test", id: "x" } },
+		{ systemPrompt: "s", messages: [] },
+		undefined,
+		{ temperature: 0 },
+	);
+	assert.equal(decision.decision, "allow");
+	assert.equal(calls[0]?.temperature, 0);
 });
 
 test("classifyWithRetry recovers when the first response is garbage and the second is valid", async () => {
@@ -478,6 +493,47 @@ test("classifyWithRetry fails closed immediately without retrying when complete
 	assert.equal(calls, 1);
 });
 
+test("classifyWithRetry surfaces provider-reported errors without retrying", async () => {
+	const response = {
+		...assistantWith("", "error"),
+		errorMessage: "Unsupported parameter: temperature",
+	};
+	const { fn, calls } = fakeComplete([response, assistantWith(VALID_ALLOW)]);
+	const attempts: ClassifierIoAttempt[] = [];
+	const decision = await classifyWithRetry(
+		fn,
+		{ model: { provider: "test", id: "x" } },
+		{ systemPrompt: "s", messages: [] },
+		undefined,
+		{ onAttempt: (attempt) => attempts.push(attempt) },
+	);
+	assert.equal(decision.decision, "block");
+	assert.match(decision.reason, /Unsupported parameter: temperature/);
+	assert.equal(calls.length, 1);
+	assert.equal(attempts[0]?.response?.errorMessage, "Unsupported parameter: temperature");
+});
+
+test("classifyWithRetry fails closed on an error stopReason with an empty message and valid allow JSON", async () => {
+	const response = {
+		...assistantWith(VALID_ALLOW, "error"),
+		errorMessage: "",
+	};
+	const { fn, calls } = fakeComplete([response, assistantWith(VALID_ALLOW)]);
+	const attempts: ClassifierIoAttempt[] = [];
+	const decision = await classifyWithRetry(
+		fn,
+		{ model: { provider: "test", id: "x" } },
+		{ systemPrompt: "s", messages: [] },
+		undefined,
+		{ onAttempt: (attempt) => attempts.push(attempt) },
+	);
+	assert.equal(decision.decision, "block");
+	assert.match(decision.reason, /Classifier model returned an error response/);
+	assert.equal(calls.length, 1);
+	assert.equal(attempts[0]?.parsed, undefined);
+	assert.equal(attempts[0]?.response?.errorMessage, "");
+});
+
 test("tool_call hook blocks permissions.deny before deterministic checks and classifier", async () => {
 	const pattern = parseToolPattern("bash(git push --force*)");
 	assert.ok(pattern);