diff --git a/open-sse/executors/commandCode.ts b/open-sse/executors/commandCode.ts
index 70453c8419..8906c01e03 100644
--- a/open-sse/executors/commandCode.ts
+++ b/open-sse/executors/commandCode.ts
@@ -145,12 +145,46 @@ function clampMaxTokens(value: unknown): number {
   return Math.max(1, Math.min(Math.floor(numeric), MAX_COMMAND_CODE_TOKENS));
 }
 
+// Reasoning/thinking fields that payload rules or clients may inject and that
+// CommandCode's upstream accepts inside `params`. Without this pass-through,
+// payload-rule overrides on these fields are silently dropped (#2986 follow-up).
+const COMMAND_CODE_PASSTHROUGH_FIELDS = [
+  "reasoning_effort",
+  "reasoning",
+  "thinking",
+  "effort",
+  "output_config",
+  "extra_body",
+] as const;
+
 function buildCommandCodeBody(model: string, body: unknown, stream = false): JsonRecord {
   const input = isRecord(body) ? body : {};
   const converted = convertMessages(input.messages);
   const explicitSystem = typeof input.system === "string" ? input.system : "";
   const system = [converted.system, explicitSystem].filter(Boolean).join("\n\n");
 
+  // Payload rules may rewrite `body.model` (e.g. deepseek-v4-pro-max →
+  // deepseek/deepseek-v4-pro for the command-code provider). Prefer the
+  // rewritten value if present; fall back to the resolved combo model arg.
+  const resolvedModel =
+    typeof input.model === "string" && input.model.trim().length > 0 ? input.model : model;
+
+  const params: JsonRecord = {
+    model: resolvedModel,
+    messages: converted.messages,
+    tools: convertTools(input.tools),
+    system,
+    max_tokens: clampMaxTokens(input.max_tokens ?? input.max_completion_tokens),
+    stream: true,
+  };
+
+  for (const field of COMMAND_CODE_PASSTHROUGH_FIELDS) {
+    const value = input[field];
+    if (value !== undefined && value !== null) {
+      params[field] = value;
+    }
+  }
+
   return {
     config: {
       workingDir: "/workspace",
@@ -167,14 +201,7 @@ function buildCommandCodeBody(model: string, body: unknown, stream = false): Jso
     taste: "",
     skills: "",
     permissionMode: "standard",
-    params: {
-      model,
-      messages: converted.messages,
-      tools: convertTools(input.tools),
-      system,
-      max_tokens: clampMaxTokens(input.max_tokens ?? input.max_completion_tokens),
-      stream: true,
-    },
+    params,
   };
 }
 
diff --git a/tests/unit/command-code-executor.test.ts b/tests/unit/command-code-executor.test.ts
index 32eaefee40..71d00f74cd 100644
--- a/tests/unit/command-code-executor.test.ts
+++ b/tests/unit/command-code-executor.test.ts
@@ -46,7 +46,7 @@ function commandCodeStream(lines: unknown[], { sse = false } = {}) {
   return new Response(text, { status: 200, headers: { "Content-Type": "application/x-ndjson" } });
 }
 
-function toPlainHeaders(headers: any) {
+function toPlainHeaders(headers: Headers | Record<string, string>) {
   if (headers instanceof Headers) return Object.fromEntries(headers.entries());
   return Object.fromEntries(Object.entries(headers).map(([key, value]) => [key, String(value)]));
 }
@@ -90,8 +90,10 @@ test("getExecutor returns the specialized Command Code executor", () => {
   assert.ok(getExecutor("cmd") instanceof CommandCodeExecutor);
 });
 
+type FetchCall = { url: string; init: Record<string, unknown>; body?: unknown };
+
 test("Command Code executor posts wrapped body and required headers to /alpha/generate", async () => {
-  const calls: any[] = [];
+  const calls: FetchCall[] = [];
   globalThis.fetch = async (url, init = {}) => {
     calls.push({ url: String(url), init });
     return commandCodeStream([{ type: "text-delta", text: "hello" }, { type: "finish" }]);
@@ -141,8 +143,66 @@ test("Command Code executor posts wrapped body and required headers to /alpha/ge
   assert.equal(json.choices[0].message.content, "hello");
 });
 
+test("Command Code executor passes reasoning/thinking fields through to params (#2986 follow-up)", async () => {
+  const calls: FetchCall[] = [];
+  globalThis.fetch = async (url, init = {}) => {
+    calls.push({ url: String(url), init });
+    return commandCodeStream([{ type: "text-delta", text: "ok" }, { type: "finish" }]);
+  };
+
+  await getExecutor("command-code").execute({
+    model: "deepseek/deepseek-v4-pro",
+    stream: false,
+    credentials: { apiKey: "cc_test_key" },
+    body: {
+      stream: false,
+      messages: [{ role: "user", content: "Hi" }],
+      reasoning_effort: "high",
+      thinking: { type: "enabled" },
+      effort: "high",
+      output_config: { effort: "high" },
+      extra_body: { enable_thinking: true },
+    },
+  });
+
+  const posted = JSON.parse(String(calls[0].init.body));
+  assert.equal(posted.params.reasoning_effort, "high");
+  assert.deepEqual(posted.params.thinking, { type: "enabled" });
+  assert.equal(posted.params.effort, "high");
+  assert.deepEqual(posted.params.output_config, { effort: "high" });
+  assert.deepEqual(posted.params.extra_body, { enable_thinking: true });
+});
+
+test("Command Code executor honors body.model rewrite from payload rules", async () => {
+  const calls: FetchCall[] = [];
+  globalThis.fetch = async (url, init = {}) => {
+    calls.push({ url: String(url), init });
+    return commandCodeStream([{ type: "text-delta", text: "ok" }, { type: "finish" }]);
+  };
+
+  // Simulate a payload-rule rewrite: combo resolves to "deepseek-v4-pro-max"
+  // (passed as the execute() model arg), but the payload rule overwrites
+  // body.model to "deepseek/deepseek-v4-pro" (the vendor-prefixed form
+  // Command Code's API expects).
+  await getExecutor("command-code").execute({
+    model: "deepseek-v4-pro-max",
+    stream: false,
+    credentials: { apiKey: "cc_test_key" },
+    body: {
+      stream: false,
+      model: "deepseek/deepseek-v4-pro",
+      messages: [{ role: "user", content: "Hi" }],
+      reasoning_effort: "max",
+    },
+  });
+
+  const posted = JSON.parse(String(calls[0].init.body));
+  assert.equal(posted.params.model, "deepseek/deepseek-v4-pro");
+  assert.equal(posted.params.reasoning_effort, "max");
+});
+
 test("Command Code raw NDJSON stream becomes OpenAI chat SSE chunks", async () => {
-  const calls: any[] = [];
+  const calls: FetchCall[] = [];
   globalThis.fetch = async (url, init = {}) => {
     calls.push({ url: String(url), init, body: JSON.parse(String(init.body)) });
     return commandCodeStream([