fix: default low thinking for reasoning models

src/gateway/protocol/schema.ts

@@ -380,6 +380,7 @@ export const ModelChoiceSchema = Type.Object(
     name: NonEmptyString,
     provider: NonEmptyString,
     contextWindow: Type.Optional(Type.Integer({ minimum: 1 })),
+    reasoning: Type.Optional(Type.Boolean()),
   },
   { additionalProperties: false },
 );

src/gateway/server.test.ts

@@ -82,6 +82,7 @@ const piSdkMock = vi.hoisted(() => ({
     name?: string;
     provider: string;
     contextWindow?: number;
+    reasoning?: boolean;
   }>,
 }));
 const cronIsolatedRun = vi.hoisted(() =>
@@ -2807,6 +2808,57 @@ describe("gateway server", () => {
     await server.close();
   });
 
+  test("chat.history defaults thinking to low for reasoning-capable models", async () => {
+    piSdkMock.enabled = true;
+    piSdkMock.models = [
+      {
+        id: "claude-opus-4-5",
+        name: "Opus 4.5",
+        provider: "anthropic",
+        reasoning: true,
+      },
+    ];
+    const dir = await fs.mkdtemp(path.join(os.tmpdir(), "clawdis-gw-"));
+    testSessionStorePath = path.join(dir, "sessions.json");
+    await fs.writeFile(
+      testSessionStorePath,
+      JSON.stringify(
+        {
+          main: {
+            sessionId: "sess-main",
+            updatedAt: Date.now(),
+          },
+        },
+        null,
+        2,
+      ),
+      "utf-8",
+    );
+    await fs.writeFile(
+      path.join(dir, "sess-main.jsonl"),
+      JSON.stringify({
+        message: {
+          role: "user",
+          content: [{ type: "text", text: "hello" }],
+          timestamp: Date.now(),
+        },
+      }),
+      "utf-8",
+    );
+
+    const { server, ws } = await startServerWithClient();
+    await connectOk(ws);
+
+    const res = await rpcReq<{ thinkingLevel?: string }>(ws, "chat.history", {
+      sessionKey: "main",
+    });
+    expect(res.ok).toBe(true);
+    expect(res.payload?.thinkingLevel).toBe("low");
+
+    ws.close();
+    await server.close();
+  });
+
   test("chat.history caps payload bytes", { timeout: 15_000 }, async () => {
     const dir = await fs.mkdtemp(path.join(os.tmpdir(), "clawdis-gw-"));
     testSessionStorePath = path.join(dir, "sessions.json");

src/gateway/server.ts

@@ -26,6 +26,7 @@ import {
   modelKey,
   resolveConfiguredModelRef,
   resolveModelRefFromString,
+  resolveThinkingDefault,
 } from "../agents/model-selection.js";
 import { installSkill } from "../agents/skills-install.js";
 import { buildWorkspaceSkillStatus } from "../agents/skills-status.js";
@@ -925,6 +926,25 @@ function getSessionDefaults(cfg: ClawdisConfig): GatewaySessionsDefaults {
   };
 }
 
+function resolveSessionModelRef(
+  cfg: ClawdisConfig,
+  entry?: SessionEntry,
+): { provider: string; model: string } {
+  const resolved = resolveConfiguredModelRef({
+    cfg,
+    defaultProvider: DEFAULT_PROVIDER,
+    defaultModel: DEFAULT_MODEL,
+  });
+  let provider = resolved.provider;
+  let model = resolved.model;
+  const storedModelOverride = entry?.modelOverride?.trim();
+  if (storedModelOverride) {
+    provider = entry?.providerOverride?.trim() || provider;
+    model = storedModelOverride;
+  }
+  return { provider, model };
+}
+
 function listSessionsFromStore(params: {
   cfg: ClawdisConfig;
   storePath: string;
@@ -3283,7 +3303,7 @@ export async function startGatewayServer(
             sessionKey: string;
             limit?: number;
           };
-          const { storePath, entry } = loadSessionEntry(sessionKey);
+          const { cfg, storePath, entry } = loadSessionEntry(sessionKey);
           const sessionId = entry?.sessionId;
           const rawMessages =
             sessionId && storePath
@@ -3296,10 +3316,22 @@ export async function startGatewayServer(
             sliced,
             MAX_CHAT_HISTORY_MESSAGES_BYTES,
           ).items;
-          const thinkingLevel =
-            entry?.thinkingLevel ??
-            loadConfig().agent?.thinkingDefault ??
-            "off";
+          let thinkingLevel = entry?.thinkingLevel;
+          if (!thinkingLevel) {
+            const configured = cfg.agent?.thinkingDefault;
+            if (configured) {
+              thinkingLevel = configured;
+            } else {
+              const { provider, model } = resolveSessionModelRef(cfg, entry);
+              const catalog = await loadGatewayModelCatalog();
+              thinkingLevel = resolveThinkingDefault({
+                cfg,
+                provider,
+                model,
+                catalog,
+              });
+            }
+          }
           return {
             ok: true,
             payloadJSON: JSON.stringify({
@@ -4668,7 +4700,7 @@ export async function startGatewayServer(
                 sessionKey: string;
                 limit?: number;
               };
-              const { storePath, entry } = loadSessionEntry(sessionKey);
+              const { cfg, storePath, entry } = loadSessionEntry(sessionKey);
               const sessionId = entry?.sessionId;
               const rawMessages =
                 sessionId && storePath
@@ -4687,10 +4719,22 @@ export async function startGatewayServer(
                 sliced,
                 MAX_CHAT_HISTORY_MESSAGES_BYTES,
               ).items;
-              const thinkingLevel =
-                entry?.thinkingLevel ??
-                loadConfig().agent?.thinkingDefault ??
-                "off";
+              let thinkingLevel = entry?.thinkingLevel;
+              if (!thinkingLevel) {
+                const configured = cfg.agent?.thinkingDefault;
+                if (configured) {
+                  thinkingLevel = configured;
+                } else {
+                  const { provider, model } = resolveSessionModelRef(cfg, entry);
+                  const catalog = await loadGatewayModelCatalog();
+                  thinkingLevel = resolveThinkingDefault({
+                    cfg,
+                    provider,
+                    model,
+                    catalog,
+                  });
+                }
+              }
               respond(true, {
                 sessionKey,
                 sessionId,