refactor(vllm): own qwen thinking payloads

extensions/vllm/api.ts

@@ -5,3 +5,4 @@ export {
   VLLM_PROVIDER_LABEL,
 } from "./defaults.js";
 export { buildVllmProvider } from "./models.js";
+export { createVllmQwenThinkingWrapper, wrapVllmProviderStream } from "./stream.js";

extensions/vllm/index.ts

@@ -10,6 +10,7 @@ import {
   VLLM_MODEL_PLACEHOLDER,
   VLLM_PROVIDER_LABEL,
 } from "./api.js";
+import { wrapVllmProviderStream } from "./stream.js";
 
 const PROVIDER_ID = "vllm";
 
@@ -89,6 +90,7 @@ export default definePluginEntry({
         "vLLM requires authentication to be registered as a provider. " +
         'Set VLLM_API_KEY (any value works) or run "openclaw configure". ' +
         "See: https://docs.openclaw.ai/providers/vllm",
+      wrapStreamFn: wrapVllmProviderStream,
     });
   },
 });

extensions/vllm/stream.test.ts

@@ -0,0 +1,170 @@
+import type { StreamFn } from "@mariozechner/pi-agent-core";
+import type { Context, Model } from "@mariozechner/pi-ai";
+import { describe, expect, it } from "vitest";
+import { createVllmQwenThinkingWrapper, wrapVllmProviderStream } from "./stream.js";
+
+function capturePayload(params: {
+  format: "chat-template" | "top-level";
+  thinkingLevel?: "off" | "low" | "medium" | "high" | "xhigh" | "max";
+  reasoning?: unknown;
+  initialPayload?: Record<string, unknown>;
+  model?: Partial<Model<"openai-completions">>;
+}): Record<string, unknown> {
+  let captured: Record<string, unknown> = {};
+  const baseStreamFn: StreamFn = (_model, _context, options) => {
+    const payload = { ...params.initialPayload };
+    options?.onPayload?.(payload, _model);
+    captured = payload;
+    return {} as ReturnType<StreamFn>;
+  };
+
+  const wrapped = createVllmQwenThinkingWrapper({
+    baseStreamFn,
+    format: params.format,
+    thinkingLevel: params.thinkingLevel ?? "high",
+  });
+  void wrapped(
+    {
+      api: "openai-completions",
+      provider: "vllm",
+      id: "Qwen/Qwen3-8B",
+      reasoning: true,
+      ...params.model,
+    } as Model<"openai-completions">,
+    { messages: [] } as Context,
+    params.reasoning === undefined ? {} : ({ reasoning: params.reasoning } as never),
+  );
+
+  return captured;
+}
+
+describe("createVllmQwenThinkingWrapper", () => {
+  it("maps Qwen chat-template thinking off to chat_template_kwargs", () => {
+    const payload = capturePayload({
+      format: "chat-template",
+      reasoning: "none",
+      initialPayload: {
+        reasoning_effort: "high",
+        reasoning: { effort: "high" },
+        reasoningEffort: "high",
+      },
+    });
+
+    expect(payload).toEqual({
+      chat_template_kwargs: {
+        enable_thinking: false,
+        preserve_thinking: true,
+      },
+    });
+  });
+
+  it("maps Qwen chat-template thinking on to chat_template_kwargs", () => {
+    expect(capturePayload({ format: "chat-template", reasoning: "medium" })).toEqual({
+      chat_template_kwargs: {
+        enable_thinking: true,
+        preserve_thinking: true,
+      },
+    });
+  });
+
+  it("preserves explicit chat-template kwargs while setting enable_thinking", () => {
+    expect(
+      capturePayload({
+        format: "chat-template",
+        thinkingLevel: "off",
+        initialPayload: {
+          chat_template_kwargs: {
+            preserve_thinking: false,
+            force_nonempty_content: true,
+          },
+        },
+      }),
+    ).toEqual({
+      chat_template_kwargs: {
+        enable_thinking: false,
+        preserve_thinking: false,
+        force_nonempty_content: true,
+      },
+    });
+  });
+
+  it("maps Qwen top-level thinking format to enable_thinking", () => {
+    expect(capturePayload({ format: "top-level", thinkingLevel: "off" })).toEqual({
+      enable_thinking: false,
+    });
+    expect(capturePayload({ format: "top-level", thinkingLevel: "high" })).toEqual({
+      enable_thinking: true,
+    });
+  });
+
+  it("skips non-reasoning and non-completions models", () => {
+    expect(capturePayload({ format: "chat-template", model: { reasoning: false } })).toEqual({});
+    expect(
+      capturePayload({ format: "chat-template", model: { api: "openai-responses" as never } }),
+    ).toEqual({});
+  });
+});
+
+describe("wrapVllmProviderStream", () => {
+  it("registers when vLLM Qwen thinking format params are configured", () => {
+    expect(
+      wrapVllmProviderStream({
+        provider: "vllm",
+        modelId: "Qwen/Qwen3-8B",
+        extraParams: { qwenThinkingFormat: "chat-template" },
+        model: {
+          api: "openai-completions",
+          provider: "vllm",
+          id: "Qwen/Qwen3-8B",
+          reasoning: true,
+        } as Model<"openai-completions">,
+        streamFn: undefined,
+      } as never),
+    ).toBeTypeOf("function");
+
+    expect(
+      wrapVllmProviderStream({
+        provider: "vllm",
+        modelId: "Qwen/Qwen3-8B",
+        extraParams: { qwen_thinking_format: "enable_thinking" },
+        model: {
+          api: "openai-completions",
+          provider: "vllm",
+          id: "Qwen/Qwen3-8B",
+          reasoning: true,
+        } as Model<"openai-completions">,
+        streamFn: undefined,
+      } as never),
+    ).toBeTypeOf("function");
+  });
+
+  it("skips unconfigured vLLM and non-vLLM providers", () => {
+    expect(
+      wrapVllmProviderStream({
+        provider: "vllm",
+        modelId: "Qwen/Qwen3-8B",
+        extraParams: {},
+        model: {
+          api: "openai-completions",
+          provider: "vllm",
+          id: "Qwen/Qwen3-8B",
+        } as Model<"openai-completions">,
+        streamFn: undefined,
+      } as never),
+    ).toBeUndefined();
+
+    expect(
+      wrapVllmProviderStream({
+        provider: "openai",
+        modelId: "gpt-5.4",
+        extraParams: { qwenThinkingFormat: "chat-template" },
+        model: {
+          api: "openai-completions",
+          provider: "openai",
+          id: "gpt-5.4",
+        } as Model<"openai-completions">,
+        streamFn: undefined,
+      } as never),
+    ).toBeUndefined();
+  });
+});

extensions/vllm/stream.ts

@@ -0,0 +1,117 @@
+import type { StreamFn } from "@mariozechner/pi-agent-core";
+import { streamSimple } from "@mariozechner/pi-ai";
+import type { ProviderWrapStreamFnContext } from "openclaw/plugin-sdk/plugin-entry";
+import { normalizeProviderId } from "openclaw/plugin-sdk/provider-model-shared";
+import { streamWithPayloadPatch } from "openclaw/plugin-sdk/provider-stream-shared";
+
+type VllmThinkingLevel = ProviderWrapStreamFnContext["thinkingLevel"];
+type VllmQwenThinkingFormat = "chat-template" | "top-level";
+
+function isVllmProviderId(providerId: string): boolean {
+  return normalizeProviderId(providerId) === "vllm";
+}
+
+function normalizeQwenThinkingFormat(value: unknown): VllmQwenThinkingFormat | undefined {
+  if (typeof value !== "string") {
+    return undefined;
+  }
+  const normalized = value.trim().toLowerCase().replace(/_/g, "-");
+  if (
+    normalized === "chat-template" ||
+    normalized === "chat-template-kwargs" ||
+    normalized === "chat-template-kwarg" ||
+    normalized === "chat-template-arguments"
+  ) {
+    return "chat-template";
+  }
+  if (
+    normalized === "top-level" ||
+    normalized === "enable-thinking" ||
+    normalized === "request-body"
+  ) {
+    return "top-level";
+  }
+  return undefined;
+}
+
+function resolveVllmQwenThinkingFormat(
+  extraParams: ProviderWrapStreamFnContext["extraParams"],
+): VllmQwenThinkingFormat | undefined {
+  return normalizeQwenThinkingFormat(
+    extraParams?.qwenThinkingFormat ?? extraParams?.qwen_thinking_format,
+  );
+}
+
+function resolveOpenAICompatibleThinkingEnabled(params: {
+  thinkingLevel: VllmThinkingLevel;
+  options: Parameters<StreamFn>[2];
+}): boolean {
+  const options = (params.options ?? {}) as { reasoningEffort?: unknown; reasoning?: unknown };
+  const raw = options.reasoningEffort ?? options.reasoning ?? params.thinkingLevel ?? "high";
+  if (typeof raw !== "string") {
+    return true;
+  }
+  const normalized = raw.trim().toLowerCase();
+  return normalized !== "off" && normalized !== "none";
+}
+
+function setQwenChatTemplateThinking(payload: Record<string, unknown>, enabled: boolean): void {
+  const existing = payload.chat_template_kwargs;
+  if (existing && typeof existing === "object" && !Array.isArray(existing)) {
+    const next: Record<string, unknown> = {
+      ...(existing as Record<string, unknown>),
+      enable_thinking: enabled,
+    };
+    if (!Object.hasOwn(next, "preserve_thinking")) {
+      next.preserve_thinking = true;
+    }
+    payload.chat_template_kwargs = next;
+    return;
+  }
+  payload.chat_template_kwargs = {
+    enable_thinking: enabled,
+    preserve_thinking: true,
+  };
+}
+
+export function createVllmQwenThinkingWrapper(params: {
+  baseStreamFn: StreamFn | undefined;
+  format: VllmQwenThinkingFormat;
+  thinkingLevel: VllmThinkingLevel;
+}): StreamFn {
+  const underlying = params.baseStreamFn ?? streamSimple;
+  return (model, context, options) => {
+    if (model.api !== "openai-completions" || !model.reasoning) {
+      return underlying(model, context, options);
+    }
+    const enableThinking = resolveOpenAICompatibleThinkingEnabled({
+      thinkingLevel: params.thinkingLevel,
+      options,
+    });
+    return streamWithPayloadPatch(underlying, model, context, options, (payloadObj) => {
+      if (params.format === "chat-template") {
+        setQwenChatTemplateThinking(payloadObj, enableThinking);
+      } else {
+        payloadObj.enable_thinking = enableThinking;
+      }
+      delete payloadObj.reasoning_effort;
+      delete payloadObj.reasoningEffort;
+      delete payloadObj.reasoning;
+    });
+  };
+}
+
+export function wrapVllmProviderStream(ctx: ProviderWrapStreamFnContext): StreamFn | undefined {
+  if (!isVllmProviderId(ctx.provider) || (ctx.model && ctx.model.api !== "openai-completions")) {
+    return undefined;
+  }
+  const format = resolveVllmQwenThinkingFormat(ctx.extraParams);
+  if (!format) {
+    return undefined;
+  }
+  return createVllmQwenThinkingWrapper({
+    baseStreamFn: ctx.streamFn,
+    format,
+    thinkingLevel: ctx.thinkingLevel,
+  });
+}