Merge pull request 'feat(qwen): Alibaba Qwen built-in over Model Studio's OpenAI-compatible mode' (#27)

README.md

@@ -122,6 +122,7 @@ Chains are health-tracked per target:
 |----------|-----------|-------------|------------------|
 | OpenAI (+compatible) | `openai` | `OPENAI_API_KEY` | https://api.openai.com/v1 |
 | Kimi (Moonshot AI) | `kimi` | `KIMI_API_KEY` | https://api.moonshot.ai/v1 |
+| Qwen (Alibaba) | `qwen` | `QWEN_API_KEY` | https://dashscope-intl.aliyuncs.com/compatible-mode/v1 |
 | Anthropic (+compatible) | `anthropic` | `ANTHROPIC_API_KEY` | https://api.anthropic.com |
 | Google (Gemini) | `google` | `GOOGLE_API_KEY` / `GEMINI_API_KEY` | Gemini API (official SDK) |
 | Ollama Cloud | `ollama-cloud` | `OLLAMA_API_KEY` | https://ollama.com |
@@ -134,6 +135,19 @@ the openai client (like llama-swap). The `kimi` built-in defaults to the
 international endpoint; reach the China endpoint (or any other host) with a
 `kimi://` DSN, e.g. `LLM_KCN=kimi://[email protected]/v1`.
 
+Qwen is the same shape: Alibaba Model Studio's OpenAI-compatible mode, reusing
+the openai client. The `qwen` built-in defaults to the international
+(Singapore) host; reach the China host or a workspace-scoped regional one with
+a `qwen://` DSN, e.g.
+`LLM_QCN=qwen://[email protected]/compatible-mode/v1`. Model Studio
+also fronts the same models with an Anthropic-compatible `/v1/messages` shim —
+majordomo does **not** use it, because on that surface `reasoning_effort` is
+dropped, `Request.Schema` stops being enforced, and cached-token accounting
+disappears; see [ADR-0027](docs/adr/0027-qwen-builtin.md). Two Alibaba-side
+quirks are worth knowing: thinking is on by default for some models (e.g.
+`qwen3.7-plus`), and the Qwen3 open-source models require streaming while
+thinking, so buffered `Generate` calls want a Max/Plus model.
+
 OpenAI-compatible / Anthropic-compatible endpoints: construct the provider
 with a name and base URL and register it —
 
@@ -165,7 +179,7 @@ m, _ := reg.Parse("m5/qwen3:30b,m1/qwen3:30b,thinking")
 ```
 
 DSN format: `scheme://[token@]host[/path]`, scheme ∈ `foreman`, `ollama`,
-`ollama-cloud`, `openai`, `kimi`, `anthropic`, `google`/`gemini`, `llama-swap`,
+`ollama-cloud`, `openai`, `kimi`, `qwen`, `anthropic`, `google`/`gemini`, `llama-swap`,
 `llama-swaps`, or any scheme you add with `RegisterScheme`. The token is the
 credential (bearer token / API key); the base URL is always `https://host[/path]`
 — except `llama-swap`, which builds `http://host[:port]` since it's local-first
@@ -420,6 +434,7 @@ to build one.
 |----------------------|:---:|:---:|:---:|:---:|:---:|:---:|:---:|
 | OpenAI (+compatible) | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ |
 | Kimi (Moonshot AI) | ✅ | ✅ | ✅ | ✅ | ✅ | ✅³ | ✅ |
+| Qwen (Alibaba) | ✅ | ✅ | ✅ | ✅ | ✅⁴ | ✅⁴ | ✅ |
 | Anthropic (+compat) | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ |
 | Google (Gemini) | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ |
 | Ollama Cloud | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ |
@@ -444,6 +459,13 @@ probe and management methods on `*llamaswap.Provider`.
 level; whether a call succeeds depends on the Moonshot model — only the vision
 variants (e.g. `moonshot-v1-8k-vision-preview`) accept images.
 
+⁴ Qwen also reuses the openai client (ADR-0027), so both columns are present at
+the client level and gated by the Model Studio model you name: `json_schema`
+structured output is on the Max/Plus families, image inputs on the `qwen-vl-*`
+/ `qwen3-vl-*` models. `reasoning_effort` rides through as a top-level field —
+one reason the built-in speaks OpenAI-compat rather than Model Studio's
+Anthropic-compat shim.
+
 Notes: Ollama has no native tool_choice — `"none"` drops the tools;
 `"required"`/named choices are best-effort ignored there. Ollama Cloud
 ignores the `format` field (verified live), so the provider also states