diff --git a/crates/agent-gui/src/lib/providers/deepSeekProviderAdapter.ts b/crates/agent-gui/src/lib/providers/deepSeekProviderAdapter.ts
index 91df5fdae..b5c42ddba 100644
--- a/crates/agent-gui/src/lib/providers/deepSeekProviderAdapter.ts
+++ b/crates/agent-gui/src/lib/providers/deepSeekProviderAdapter.ts
@@ -377,6 +377,8 @@ export function attachDeepSeekProviderPayloadAdapter<TOptions extends DeepSeekSt
   },
 ): TOptions {
   const model = params.model;
+  // DeepSeek adapter 只服务实际选中的 chat/anthropic 协议；Responses 由用户配置决定。
+  if (params.providerId === "codex" && model && model.api !== "openai-completions") return options;
   const isDeepSeek =
     params.providerId === "codex"
       ? isDeepSeekCodexTarget({
diff --git a/crates/agent-gui/src/lib/providers/runtime/modelFactory.ts b/crates/agent-gui/src/lib/providers/runtime/modelFactory.ts
index bf1913486..516fb5e7e 100644
--- a/crates/agent-gui/src/lib/providers/runtime/modelFactory.ts
+++ b/crates/agent-gui/src/lib/providers/runtime/modelFactory.ts
@@ -20,7 +20,6 @@ import {
 } from "../anthropicModels";
 import {
   applyDeepSeekModelDefaults,
-  isDeepSeekCodexTarget,
   resolveDeepSeekOpenAICompletionsOverrides,
 } from "../deepSeekProviderAdapter";
 import { isXaiProviderTarget } from "./xaiResponsesPayload";
@@ -334,24 +333,13 @@ export function createModelFromConfig(
 
   if (providerId === "codex" || providerId === "xai") {
     const { baseUrl: normalizedBaseUrl, preferredApi } = normalizeCodexBaseUrl(baseUrl);
-    const isDeepSeekCodex =
-      providerId === "codex" &&
-      isDeepSeekCodexTarget({
-        providerId,
-        baseUrl: normalizedBaseUrl,
-        upstreamBaseUrl,
-        modelId,
-      });
     // 正式 xai 供应商，或 Codex 直连 api.x.ai：固定 Responses（agentic 搜索等）。
     const isXaiTarget = isXaiProviderTarget({
       providerId,
       baseUrl: upstreamBaseUrl?.trim() || baseUrl,
     });
-    const api = isDeepSeekCodex
-      ? "openai-completions"
-      : isXaiTarget
-        ? "openai-responses"
-        : inferCodexApi(requestFormat, preferredApi);
+    // DeepSeek 不再按模型 ID 强制协议；requestFormat 优先，DeepSeek 适配只在最终走 completions 时生效。
+    const api = isXaiTarget ? "openai-responses" : inferCodexApi(requestFormat, preferredApi);
     const responsesCompat =
       api === "openai-responses"
         ? resolveCodexOpenAIResponsesCompat({
diff --git a/crates/agent-gui/test/providers/request-options.test.mjs b/crates/agent-gui/test/providers/request-options.test.mjs
index ca5ad7f5a..9878aed4c 100644
--- a/crates/agent-gui/test/providers/request-options.test.mjs
+++ b/crates/agent-gui/test/providers/request-options.test.mjs
@@ -536,80 +536,6 @@ test("Codex Chat Completions streams forward reasoning effort", async () => {
   assert.equal(captured.options.toolChoice, "auto");
 });
 
-test("DeepSeek Codex models force Chat Completions compat", () => {
-  const model = providers.createModelFromConfig(
-    "codex",
-    "deepseek-v4-pro",
-    "https://api.deepseek.com",
-    "openai-responses",
-  );
-
-  assert.equal(model.api, "openai-completions");
-  assert.equal(model.reasoning, true);
-  assert.equal(model.compat.thinkingFormat, "deepseek");
-  assert.equal(model.compat.requiresReasoningContentOnAssistantMessages, true);
-  assert.equal(model.compat.supportsStrictMode, false);
-  assert.equal(model.compat.maxTokensField, "max_tokens");
-  // 档位来自生成目录：deepseek-v4-pro 只有 high/max（minimal/low/medium=null），
-  // xhigh 目录未声明故不复活；wire 改写只补到已支持档位（high→"high"）。
-  assert.equal(model.thinkingLevelMap.minimal, null);
-  assert.equal(model.thinkingLevelMap.high, "high");
-  assert.equal(model.thinkingLevelMap.xhigh, undefined);
-  assert.equal(model.thinkingLevelMap.max, "max");
-});
-
-test("DeepSeek OpenAI payload adapter injects thinking and reasoning_content", async () => {
-  let captured;
-  const localLoader = createTsModuleLoader({
-    mocks: {
-      "@earendil-works/pi-ai/api/openai-completions": {
-        stream(model, context, options) {
-          captured = { model, context, options };
-          return createMockAssistantStream();
-        },
-      },
-    },
-  });
-  const localProviders = localLoader.loadModule("src/lib/providers/llm.ts");
-  const model = localProviders.createModelFromConfig(
-    "codex",
-    "deepseek-v4-pro",
-    "https://api.deepseek.com",
-    "openai-responses",
-  );
-
-  const result = localProviders.streamSimpleByApi(
-    model,
-    { messages: [] },
-    { reasoning: "minimal", toolChoice: "auto" },
-  );
-  assert.equal(typeof result.result, "function");
-  assert.equal(typeof captured.options.onPayload, "function");
-
-  const adapted = await captured.options.onPayload(
-    {
-      messages: [
-        {
-          role: "assistant",
-          content: null,
-          tool_calls: [
-            {
-              id: "call_1",
-              type: "function",
-              function: { name: "Read", arguments: "{}" },
-            },
-          ],
-        },
-      ],
-    },
-    model,
-  );
-
-  assert.deepEqual(adapted.thinking, { type: "enabled" });
-  assert.equal(adapted.reasoning_effort, "high");
-  assert.equal(adapted.messages[0].reasoning_content, "");
-});
-
 test("DeepSeek Anthropic streamSimpleByApi strips aborted tool calls before conversion", () => {
   const { localProviders, state } = loadProvidersWithCapturedAnthropicStream();
   const model = createDeepSeekAnthropicModel();