diff --git a/.agents/docs/mcppls-integration.md b/.agents/docs/mcppls-integration.md
index 3e85850..d3a0695 100644
--- a/.agents/docs/mcppls-integration.md
+++ b/.agents/docs/mcppls-integration.md
@@ -43,7 +43,7 @@ mcppls 侧**没有** `extensionDependencies`：依赖是单向的。
 | `mcppls.collectReport` | 收集诊断报告 | none |
 | `mcppls.exportDiagnosticBundle` | 导出诊断包（服务器命令 `mcppls.exportBundle`） | none |
 | `mcppls.runBuildToolInTerminal` | 在集成终端运行构建工具 | confirm |
-| `mcppls.turnOffOtherCppFeatures` / `mcppls.restoreOtherCppFeatures` | 关闭/恢复其它 C++ 扩展的语言特性（**会写别的扩展自己的设置**，由 mcppls 执行） | confirm |
+| `mcppls.turnOffOtherCppFeatures` / `mcppls.restoreOtherCppFeatures` | 关闭/恢复其它 C++ 扩展的语言特性（**会写别的扩展自己的设置**，由 mcppls 执行；它自己先问作用范围，关掉问题即不执行）。0.7.0 起是两条能力，不再共用一条候选链 | none |
 | `mcppls.turnOnInWorkspace` / `mcppls.turnOffInWorkspace` | 在本工作区启用/停用 C++ Modules（**会写 `mcppls.enable`**，由 mcppls 执行） | confirm |
 | `mcppls.installCommandLineTools` | macOS 命令行工具 | confirm |
 | `mcppls.review.run` / `mcppls.review.clear` | Review Changes（**服务器广告**的命令，服务器运行后才存在；受 `mcppls.ai.enabled` 约束） | none |
@@ -120,6 +120,7 @@ VS Code 命令，重名会让 mcppls 的语言客户端启动失败。mcppls 因
 | `serverCommands(): string[]` | ✅（服务器未运行时为空数组） | 判断服务器是否广告了某命令 |
 | `environment()` | ✅ | version / vscode / appName / appHost / uiKind / platform / remote |
 | `waitForState()` | ✅ | 需要等待某个状态时使用 |
+| `otherCppFeatures(): { active: { extensionId, displayName, settable }[]; canRestore }` | ✅（mcppls 0.0.16 起） | 「其他 C++ 语言服务」一行：哪些在工作、mcppls 能否恢复。缺失、抛错或形状不对时退回本地只读检测（`src/mcppls/otherCppFeatures.ts`，同三个候选），`canRestore` 为 false |
 | 计数器类（`notificationCount` 等） | ❌ 非测试模式下返回 `-1`/`0` | **不使用** |
 
 **使用纪律**（写进 `mcpp-vscode/src/mcppls/state.ts`，并有单测与 e2e 覆盖）：
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 54ad9ff..9d41f52 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,50 @@
+## 0.7.0 - 2026-10-14
+
+`build.mcpp` is C++ again, compiled by C++ Modules as the build program it is, and the project
+view says when another C++ language service is answering the same files.
+
+### Changed
+
+- **`build.mcpp` is a `cpp` document.** 0.6.0 gave it a language of its own, `mcpp-build`.
+  VS Code prefers a filename match over an extension match, so that hid the file from C++
+  Modules, which selects `cpp`: the build program got a line-by-line text check instead of a
+  compiler. The `mcpp-build` language, its grammar and its language configuration are gone;
+  this extension's build-script help now registers on `cpp` documents named `build.mcpp`, and
+  the C++ module grammar is injected into `source.cpp` only.
+- **While C++ Modules serves `build.mcpp`, it answers what it answers better**: the
+  `unknownSymbol` check and the module names after `import` (completion and hover) are left to
+  it. The SPEC-007 rule checks, the `mcpp::…` directive completion and hover, and the snippets
+  stay. "Serves" means the extension is installed and enabled and `mcppls.enable` is not
+  `false` here; the open files are re-checked when that changes.
+- **`unknownSymbol` reads the file's imports** when it does run: `import mcpp.rules.qt;` makes
+  `mcpp::rules::…` a name the snapshot cannot judge, so it is no longer reported
+  (`unknown mcpp::rules` on every Qt build program).
+- The diagnostics' owner is `mcpp-build-script` (was `mcpp-build`).
+- The build-script snapshot and the `mcpp.toml` schema are regenerated from mcpp 2026.10.11.1.
+  The schema generator reads the `[build]` keys from mcpp's key registry, where 2026.10.11.1
+  moved them.
+
+### Added
+
+- **Project → Basics → Language service → "Other C++ language services".** While C/C++
+  IntelliSense, clangd or ccls is active next to C++ Modules, the row shows a warning and their
+  names, and one click runs C++ Modules' own **Turn Off Other C++ Language Services** (it asks
+  whether for this workspace or everywhere, and writes the other extensions' own settings).
+  With none, the row is a dimmed check mark, "Only C++ Modules is serving C++". When C++
+  Modules remembers what it turned off, the row's context menu offers **Restore**. The list is
+  C++ Modules' own answer (0.0.16+); with an older one, a read-only look at the same three
+  extensions.
+- `mcpp.languageServer.restoreConflicts` ("C++ Modules: Restore Other C++ Language Services").
+  `mcpp.languageServer.manageConflicts` is now titled "Turn Off Other C++ Language Services",
+  which is what it always ran.
+
+### Migrating
+
+- A setting written for the old language id, `"[mcpp-build]": { … }` in `settings.json`, no
+  longer applies. Move it under `"[cpp]"`.
+- Turning other C++ services off or restoring them no longer asks a second time in this
+  extension: C++ Modules' command asks where to act, and closing that question does nothing.
+
 ## 0.6.0 - 2026-10-02
 
 The sidebar was reorganised around one rule: **the body shows state, the actions sit
diff --git a/README.md b/README.md
index 2855e55..403e047 100644
--- a/README.md
+++ b/README.md
@@ -52,7 +52,7 @@ Opening a project never runs `mcpp` on its own and never downloads a toolchain.
 
 - **mcpp CLI and tasks** — build, run, test, clean, the quick menu, toolchains: [docs/commands.md](docs/commands.md).
 - **`mcpp.toml` editing** — structural completion, hovers, go-to-definition, seven structural diagnostics, no formatting: [docs/mcpp-toml.md](docs/mcpp-toml.md).
-- **`build.mcpp` intelligence** — completion and hovers for `mcpp::…` and `import`, seven SPEC-007 diagnostics, never a spurious "module not found": [docs/build-script.md](docs/build-script.md).
+- **`build.mcpp` help** — `build.mcpp` is a `cpp` file that C++ Modules compiles as the build program; this extension adds the `mcpp::…` directive completion, hovers and snippets and the SPEC-007 rule checks no compiler makes: [docs/build-script.md](docs/build-script.md).
 - **Libraries** — browse the package index already on this machine, offline; the detail page shows the real example code, the version matrix, and whether the workspace already depends on it.
 - **Cache views and cleanup** — project artifacts and the shared build cache, previewed before anything is deleted: [docs/cache.md](docs/cache.md).
 - **C++ Modules** — the other extension's state and actions, in the project view and the status-bar menu, forwarded not reimplemented: [docs/commands.md](docs/commands.md).
diff --git a/README.zh-CN.md b/README.zh-CN.md
index 64351c0..cf422be 100644
--- a/README.zh-CN.md
+++ b/README.zh-CN.md
@@ -52,7 +52,7 @@ C++ 模块语义——诊断、补全、悬停、定义、引用、模块图—
 
 - **mcpp CLI 与任务** —— 构建、运行、测试、清理、快捷菜单、工具链：[docs/commands.md](docs/commands.md)。
 - **`mcpp.toml` 编辑** —— 结构补全、悬停、跳转与七条结构诊断，不做格式化：[docs/mcpp-toml.md](docs/mcpp-toml.md)。
-- **`build.mcpp` 智能** —— `mcpp::…` 与 `import` 的补全悬停、七条 SPEC-007 诊断，且永不误报「模块找不到」：[docs/build-script.md](docs/build-script.md)。
+- **`build.mcpp` 辅助** —— `build.mcpp` 是普通的 `cpp` 文件，由 C++ Modules 当作构建程序编译；本扩展补上 `mcpp::…` 指令的补全、悬停、代码片段，以及编译器不会检查的 SPEC-007 规则：[docs/build-script.md](docs/build-script.md)。
 - **库生态** —— 离线浏览本机已刷新的包索引；详情页展示真实示例代码、版本矩阵，以及工程是否已依赖它。
 - **缓存视图与清理** —— 工程产物与共享缓存，删除前一律先给出预览：[docs/cache.md](docs/cache.md)。
 - **C++ Modules** —— 对方扩展的状态与操作，集中在工程视图与状态栏快捷菜单，只转发不重写：[docs/commands.md](docs/commands.md)。
diff --git a/data/buildscript-api.json b/data/buildscript-api.json
index f8e1027..3cb51b1 100644
--- a/data/buildscript-api.json
+++ b/data/buildscript-api.json
@@ -1,6 +1,6 @@
 {
-  "sourceVersion": "2026.10.3.1",
-  "sourceCommit": "74bcb859e60afc71ad759540d2de5344dda400e9",
+  "sourceVersion": "2026.10.11.1",
+  "sourceCommit": "3fb2d0cc89296c527fcda710792b67bb7a481bed",
   "protocolVersion": 15,
   "cacheEpoch": 3,
   "roles": [
@@ -118,7 +118,8 @@
       "rules": [
         "R2.1",
         "R3.3",
-        "R3.6"
+        "R3.6",
+        "R3.9"
       ],
       "docsUrl": null
     },
@@ -131,7 +132,7 @@
       "mustExist": false,
       "since": 4,
       "rules": [],
-      "docsUrl": "https://github.com/mcpp-community/mcpp/blob/74bcb859e60afc71ad759540d2de5344dda400e9/docs/30-build-mcpp.md#runner-how-the-artifact-is-executed-20268192"
+      "docsUrl": "https://github.com/mcpp-community/mcpp/blob/3fb2d0cc89296c527fcda710792b67bb7a481bed/docs/30-build-mcpp.md#runner-how-the-artifact-is-executed-20268192"
     },
     {
       "wire": "runner-named",
@@ -262,7 +263,7 @@
         "R2.1",
         "R9.4"
       ],
-      "docsUrl": "https://github.com/mcpp-community/mcpp/blob/74bcb859e60afc71ad759540d2de5344dda400e9/docs/30-build-mcpp.md#warning-succeeding-and-still-being-heard-20268212"
+      "docsUrl": "https://github.com/mcpp-community/mcpp/blob/3fb2d0cc89296c527fcda710792b67bb7a481bed/docs/30-build-mcpp.md#warning-succeeding-and-still-being-heard-20268212"
     },
     {
       "wire": "diagnostic",
@@ -294,6 +295,7 @@
         "R3.5",
         "R3.7",
         "R3.8",
+        "R3.9",
         "R5.1",
         "R5.3",
         "R6.4",
@@ -312,7 +314,7 @@
       "rules": [
         "R2.1"
       ],
-      "docsUrl": "https://github.com/mcpp-community/mcpp/blob/74bcb859e60afc71ad759540d2de5344dda400e9/docs/30-build-mcpp.md#the-probe-channel-fact-floor-2026952"
+      "docsUrl": "https://github.com/mcpp-community/mcpp/blob/3fb2d0cc89296c527fcda710792b67bb7a481bed/docs/30-build-mcpp.md#the-probe-channel-fact-floor-2026952"
     },
     {
       "wire": "floor",
@@ -325,7 +327,7 @@
       "rules": [
         "R2.1"
       ],
-      "docsUrl": "https://github.com/mcpp-community/mcpp/blob/74bcb859e60afc71ad759540d2de5344dda400e9/docs/30-build-mcpp.md#the-probe-channel-fact-floor-2026952"
+      "docsUrl": "https://github.com/mcpp-community/mcpp/blob/3fb2d0cc89296c527fcda710792b67bb7a481bed/docs/30-build-mcpp.md#the-probe-channel-fact-floor-2026952"
     },
     {
       "wire": "pack-format",
@@ -374,7 +376,7 @@
         "R9.2",
         "R9.5"
       ],
-      "docsUrl": "https://github.com/mcpp-community/mcpp/blob/74bcb859e60afc71ad759540d2de5344dda400e9/docs/30-build-mcpp.md#deploying-what-the-program-generated-deploy-20269123-protocol-11"
+      "docsUrl": "https://github.com/mcpp-community/mcpp/blob/3fb2d0cc89296c527fcda710792b67bb7a481bed/docs/30-build-mcpp.md#deploying-what-the-program-generated-deploy-20269123-protocol-11"
     },
     {
       "wire": "runtime-search-dir",
diff --git a/data/i18n/zh-cn.json b/data/i18n/zh-cn.json
index ce3bb1b..a326dd4 100644
--- a/data/i18n/zh-cn.json
+++ b/data/i18n/zh-cn.json
@@ -467,5 +467,9 @@
   "Could not write the clipboard.": "无法写入剪贴板。",
   "The workspace is not trusted; mcpp itself was not probed.": "工作区未受信任；未探测 mcpp 本身。",
   "This workspace is not trusted, so mcpp is not run; the versions below come from the descriptor's text.": "工作区未受信任，因此不运行 mcpp；下面的版本来自描述符文本。",
-  "The workspace is not trusted; the other registries were not searched.": "工作区未受信任；未搜索其他 registry。"
+  "The workspace is not trusted; the other registries were not searched.": "工作区未受信任；未搜索其他 registry。",
+  "Only C++ Modules is serving C++": "仅 C++ Modules 在提供 C++ 语言服务",
+  "No other C++ language service (C/C++, clangd, ccls) is active, so no result is shown twice.": "没有其他 C++ 语言服务（C/C++、clangd、ccls）在工作，结果不会重复出现。",
+  "Other C++ language services": "其他 C++ 语言服务",
+  "They answer the same C++ files, so results appear twice. Click to turn their C++ language features off; C++ Modules asks whether for this workspace or everywhere.": "它们也在处理同一批 C++ 文件，结果会出现两次。点击即可关闭它们的 C++ 语言功能；C++ Modules 会询问只对本工作区还是对所有地方生效。"
 }
diff --git a/data/toml-schema.json b/data/toml-schema.json
index bd44b66..c5fe572 100644
--- a/data/toml-schema.json
+++ b/data/toml-schema.json
@@ -1,6 +1,6 @@
 {
-  "sourceVersion": "2026.10.3.1",
-  "sourceCommit": "74bcb859e60afc71ad759540d2de5344dda400e9",
+  "sourceVersion": "2026.10.11.1",
+  "sourceCommit": "3fb2d0cc89296c527fcda710792b67bb7a481bed",
   "sections": [
     {
       "header": "[build]",
@@ -690,6 +690,11 @@
           "key": "soname",
           "type": "string"
         },
+        {
+          "key": "windows_auto_export",
+          "type": "string",
+          "unmodelled": true
+        },
         {
           "key": "windows_code_page",
           "type": "enum",
@@ -778,7 +783,7 @@
       "header": "[workspace]",
       "name": "workspace",
       "plane": "unclassified",
-      "doc": "https://github.com/mcpp-community/mcpp/blob/main/docs/04-mcpp-toml.md",
+      "doc": "https://github.com/mcpp-community/mcpp/blob/main/docs/04-mcpp-toml.md#218-workspace--tables-a-workspace-shares-202610101",
       "deprecatedBy": null
     },
     {
diff --git a/docs/build-script.md b/docs/build-script.md
index 9913d9d..ee10298 100644
--- a/docs/build-script.md
+++ b/docs/build-script.md
@@ -1,38 +1,35 @@
 # Editing `build.mcpp`
 
 `build.mcpp` is mcpp's build program: C++ that the engine compiles and runs to produce the
-build graph. It gets its own language id, `mcpp-build` (exact filename `build.mcpp`), with the
-TextMate grammar `source.mcpp-build` from `syntaxes/mcpp-build.tmLanguage.json`; the module
-grammar `source.cpp.mcpp-modules` is injected into both `source.cpp` and `source.mcpp-build`.
-
-## Why it is not handed to the C++ language service
-
-Measured on a real mcppls payload with clangd 23.1.0, handing `build.mcpp` to the C++ language
-service fails for **both** `import std;` and `import mcpp;`:
-
-```text
-$ mcppls check build.mcpp --payload <payload>
-root      …/examples/11-features/greeter
-database  6 entries, 2 standard library units, 0 left out
-module    build.mcpp:2: module 'mcpp' not found
-E [module_not_found] Line 1: module 'std' not found
-E Failed to build module mcpp; due to Don't get the module unit for module mcpp
-clangd    exit 3
-
-$ mcppls check src/main.cpp --payload <payload>
-database  6 entries, 2 standard library units, 0 left out
-clangd    exit 0
-```
-
-The reason is in the build database: `mcpp emit build-database --spec compile-commands --format
-json` lists 6 records and **none of them is `build.mcpp`** — it only appears under `data.watch`.
-mcpp deliberately does not put the build program into the compilation database, and mcppls's
-model has no `build.mcpp` (it handles `target/.build-mcpp/deps/…`). So this is not "only `mcpp`
-is missing": `std` fails too, and VS Code has no public API to filter a diagnostic another
-extension published.
-
-**Therefore `build.mcpp` stays in its own language id and the C++ language service never sees
-it.** This extension analyses the file itself, and it never reports any import as missing.
+build graph. **It is an ordinary `cpp` document** (this extension declares the filename for the
+`cpp` language, and C++ Modules associates `.mcpp` with `cpp` too); the module grammar
+`source.cpp.mcpp-modules` is injected into `source.cpp`.
+
+## Who answers what
+
+C++ Modules (mcppls, 0.0.12 and later) compiles `build.mcpp` as the build program it is: against
+the modules it really imports, `mcpp`, `std` and the plugins named in
+`[build-dependencies]`, with the toolchain the build uses. Its completion, hover, navigation and
+diagnostics are a compiler's. This extension adds what no compiler says:
+
+| | C++ Modules serves the file | C++ Modules is disabled or switched off here |
+| --- | --- | --- |
+| SPEC-007 rule checks (six of the seven rules below) | this extension | this extension |
+| `unknownSymbol` | off — the compiler's answer replaces it | this extension, import-aware |
+| `mcpp::…` directive completion and hover, snippets | this extension | this extension |
+| Module names after `import` (completion, hover) | C++ Modules | this extension |
+
+"Serves" is read without asking anything of the language server: the C++ Modules extension is
+installed and enabled, and `mcppls.enable` is not `false` for the workspace. When that changes
+(the extension is enabled, disabled, or switched off for the workspace) the open `build.mcpp`
+files are re-checked at once.
+
+Up to 0.6.0 this extension gave `build.mcpp` a language id of its own, `mcpp-build`. VS Code
+prefers a filename match over an extension match, so that hid the file from C++ Modules, which
+selects `cpp` documents: the build program got a line-by-line text check instead of a compiler,
+and `import mcpp.rules.qt;` followed by `mcpp::rules::qt::…` was reported as an unknown name.
+A setting written for that language (`"[mcpp-build]": { … }`) no longer applies; write it under
+`"[cpp]"`.
 
 ## What this extension provides
 
@@ -42,19 +39,20 @@ work in an untrusted workspace.
 
 ### Completion
 
-Registered for the `mcpp-build` language in `src/buildscript/providers.ts`.
+Registered for `cpp` documents named `build.mcpp`, in `src/buildscript/providers.ts`.
 
 - After `mcpp::` (or `mcpp::pre`): directive names, from the 31 entries in the snapshot's
   `directives` array, with `-` rewritten to `_` (so the wire name `link-flag` offers
   `link_flag`). Kind: function.
-- After `import ` or `export import `: the concrete module names from the known-module table
-  (the `prefix.*` patterns are not offered as literal text). Kind: module, with the module's
-  description as documentation.
+- After `import ` or `export import `, only while C++ Modules does not serve the file: the
+  concrete module names from the known-module table (the `prefix.*` patterns are not offered as
+  literal text). Kind: module, with the module's description as documentation.
 
 ### Hover
 
-- On a known module name in an `import`: the module name and its description (for a
-  `prefix.*` match, the concrete name the user wrote is shown).
+- On a known module name in an `import`, only while C++ Modules does not serve the file: the
+  module name and its description (for a `prefix.*` match, the concrete name the user wrote is
+  shown).
 - On `mcpp::<name>`: the wire spelling (`mcpp:<wire>=`), `slot`, `scope`, `since protocol`, the
   SPEC-007 rules and a link into mcpp's `docs/30-build-mcpp.md`.
 
@@ -78,7 +76,7 @@ diagnostic's `code`; `source` is `mcpp`.
 
 | Code | What it flags | SPEC-007 |
 | --- | --- | --- |
-| `mcpp.buildscript.unknownSymbol` | An `mcpp::<name>` that is not a directive, an action role or a typed-API name in the snapshot | §2 |
+| `mcpp.buildscript.unknownSymbol` | An `mcpp::<name>` that is not a directive, an action role or a typed-API name in the snapshot, and not a namespace the file imports (`import mcpp.rules.qt;` covers `mcpp::rules::…`). Only while C++ Modules does not serve the file | §2 |
 | `mcpp.buildscript.roleLiteral` | `role = "<known role>"`; use `mcpp::roles::<role>` so an engine that does not know it refuses to compile | R3.6 |
 | `mcpp.buildscript.prepareNeedsOutputDir` | A `prepare` action with no `output_dir(…)` | R3.3 |
 | `mcpp.buildscript.rpathInLinkFlag` | `-Wl,-rpath` in `link_flag`; use `mcpp::runtime_search_dir(…)` | R4.4 |
@@ -113,8 +111,8 @@ the raw-string and block-comment state carries across lines.
 
 | Field | Value |
 | --- | --- |
-| `sourceVersion` | `2026.10.1.3` |
-| `sourceCommit` | `4d81d062` |
+| `sourceVersion` | `2026.10.11.1` |
+| `sourceCommit` | `3fb2d0cc` |
 | `protocolVersion` | `15` |
 | `cacheEpoch` | `3` |
 | `roles` | `source`, `check`, `object`, `artifact`, `prepare` |
diff --git a/docs/commands.md b/docs/commands.md
index 0c96bbb..b3d7902 100644
--- a/docs/commands.md
+++ b/docs/commands.md
@@ -77,11 +77,21 @@ behaviour. The capability table is `src/mcppls/contract.ts`, the probe is
 | `mcpp.languageServer.collectReport` | `command.mcpp.languageServer.collectReport.title` | `mcppls.collectReport` | none |
 | `mcpp.languageServer.exportDiagnosticBundle` | `command.mcpp.languageServer.exportDiagnosticBundle.title` | `mcppls.exportDiagnosticBundle` | none |
 | `mcpp.languageServer.runBuildToolInTerminal` | `command.mcpp.languageServer.runBuildToolInTerminal.title` | `mcppls.runBuildToolInTerminal` | confirm |
-| `mcpp.languageServer.manageConflicts` | `command.mcpp.languageServer.manageConflicts.title` | `mcppls.turnOffOtherCppFeatures` / `mcppls.restoreOtherCppFeatures`, called with `true` | confirm |
+| `mcpp.languageServer.manageConflicts` | `command.mcpp.languageServer.manageConflicts.title` | `mcppls.turnOffOtherCppFeatures` (it asks where: this workspace or user settings) | none |
+| `mcpp.languageServer.restoreConflicts` | `command.mcpp.languageServer.restoreConflicts.title` | `mcppls.restoreOtherCppFeatures` | none |
 | `mcpp.languageServer.toggleInWorkspace` | `command.mcpp.languageServer.toggleInWorkspace.title` | `mcppls.turnOffInWorkspace` / `mcppls.turnOnInWorkspace`, called with `!mcppls.enable` | confirm |
 | `mcpp.languageServer.installTools` | `command.mcpp.languageServer.installTools.title` | `mcppls.installCommandLineTools` | confirm |
 | `mcpp.languageServer.reviewChanges` | `command.mcpp.languageServer.reviewChanges.title` | `mcppls.review.run` / `mcppls.review.clear`, called with `false` | none |
 
+**Project → Basics → Language service** carries one row for the other C++ language services
+(C/C++ IntelliSense, clangd, ccls). While one is active it shows a warning and their names, and
+clicking it runs `mcpp.languageServer.manageConflicts`; with none it is a dimmed check mark,
+"Only C++ Modules is serving C++", with nothing to click. When mcppls remembers settings it
+turned off, the row's context menu offers `mcpp.languageServer.restoreConflicts`. The list comes
+from mcppls itself (`otherCppFeatures()` on its extension API, 0.0.16+) and, from an older
+mcppls, from a read-only look at the same three extensions and their settings. This extension
+never writes those settings: mcppls's command does, at their own keys.
+
 `refresh` for the build path uses a candidate chain
 (`mcppls.reloadBuildDescription`, then `mcppls.restartServer`) and is single-flight, so two
 builds cannot restart the language server twice. `mcpp.languageService.refreshAfterBuild` is
diff --git a/l10n/bundle.l10n.zh-cn.json b/l10n/bundle.l10n.zh-cn.json
index ae2ad3e..a326dd4 100644
--- a/l10n/bundle.l10n.zh-cn.json
+++ b/l10n/bundle.l10n.zh-cn.json
@@ -363,7 +363,6 @@
   "Workspace settings": "工作区设置",
   "added": "已添加",
   "convention {0}": "约定 {0}",
-  "dev": "dev",
   "dev dependency": "dev 依赖",
   "git · {0}": "git · {0}",
   "host default": "host 默认",
@@ -460,5 +459,17 @@
   "{0}{1}": "{0}{1}",
   "{0}–{1} day(s)": "{0}–{1} 天",
   "{0}–{1} day(s) ago": "{0}–{1} 天前",
-  "✓ Has examples": "✓ 有示例"
+  "✓ Has examples": "✓ 有示例",
+  "Bring it into your code": "在代码里引入",
+  "Copy": "复制",
+  "Copied to the clipboard.": "已复制到剪贴板。",
+  "Copying…": "复制中…",
+  "Could not write the clipboard.": "无法写入剪贴板。",
+  "The workspace is not trusted; mcpp itself was not probed.": "工作区未受信任；未探测 mcpp 本身。",
+  "This workspace is not trusted, so mcpp is not run; the versions below come from the descriptor's text.": "工作区未受信任，因此不运行 mcpp；下面的版本来自描述符文本。",
+  "The workspace is not trusted; the other registries were not searched.": "工作区未受信任；未搜索其他 registry。",
+  "Only C++ Modules is serving C++": "仅 C++ Modules 在提供 C++ 语言服务",
+  "No other C++ language service (C/C++, clangd, ccls) is active, so no result is shown twice.": "没有其他 C++ 语言服务（C/C++、clangd、ccls）在工作，结果不会重复出现。",
+  "Other C++ language services": "其他 C++ 语言服务",
+  "They answer the same C++ files, so results appear twice. Click to turn their C++ language features off; C++ Modules asks whether for this workspace or everywhere.": "它们也在处理同一批 C++ 文件，结果会出现两次。点击即可关闭它们的 C++ 语言功能；C++ Modules 会询问只对本工作区还是对所有地方生效。"
 }
diff --git a/package-lock.json b/package-lock.json
index 0156104..562b7fd 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "mcpp-vscode",
-  "version": "0.6.0",
+  "version": "0.7.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "mcpp-vscode",
-      "version": "0.6.0",
+      "version": "0.7.0",
       "license": "Apache-2.0",
       "devDependencies": {
         "@types/mocha": "^10.0.10",
diff --git a/package.json b/package.json
index f90d2ad..1e279de 100644
--- a/package.json
+++ b/package.json
@@ -2,7 +2,7 @@
   "name": "mcpp-vscode",
   "displayName": "%displayName%",
   "description": "%description%",
-  "version": "0.6.0",
+  "version": "0.7.0",
   "publisher": "mcpp-community",
   "license": "Apache-2.0",
   "icon": "media/logo.png",
@@ -22,8 +22,7 @@
   ],
   "activationEvents": [
     "workspaceContains:mcpp.toml",
-    "onLanguage:mcpp-toml",
-    "onLanguage:mcpp-build"
+    "onLanguage:mcpp-toml"
   ],
   "categories": [
     "Programming Languages",
@@ -71,6 +70,12 @@
           "command": "mcpp.openMcpplsSettings",
           "when": "false"
         }
+      ],
+      "view/item/context": [
+        {
+          "command": "mcpp.languageServer.restoreConflicts",
+          "when": "view == mcpp.project && viewItem =~ /^mcppOtherCppFeatures.*Restorable$/"
+        }
       ]
     },
     "commands": [
@@ -246,6 +251,11 @@
         "title": "%command.mcpp.languageServer.manageConflicts.title%",
         "category": "%category%"
       },
+      {
+        "command": "mcpp.languageServer.restoreConflicts",
+        "title": "%command.mcpp.languageServer.restoreConflicts.title%",
+        "category": "%category%"
+      },
       {
         "command": "mcpp.languageServer.toggleInWorkspace",
         "title": "%command.mcpp.languageServer.toggleInWorkspace.title%",
@@ -990,15 +1000,10 @@
     },
     "languages": [
       {
-        "id": "mcpp-build",
-        "aliases": [
-          "mcpp build script",
-          "build.mcpp"
-        ],
+        "id": "cpp",
         "filenames": [
           "build.mcpp"
-        ],
-        "configuration": "./syntaxes/mcpp-build-language-configuration.json"
+        ]
       },
       {
         "id": "mcpp-toml",
@@ -1020,11 +1025,6 @@
       }
     },
     "grammars": [
-      {
-        "language": "mcpp-build",
-        "scopeName": "source.mcpp-build",
-        "path": "./syntaxes/mcpp-build.tmLanguage.json"
-      },
       {
         "language": "mcpp-toml",
         "scopeName": "source.toml.mcpp",
@@ -1033,8 +1033,7 @@
       {
         "scopeName": "source.cpp.mcpp-modules",
         "injectTo": [
-          "source.cpp",
-          "source.mcpp-build"
+          "source.cpp"
         ],
         "path": "./syntaxes/mcpp-modules.tmLanguage.json"
       }
diff --git a/package.nls.json b/package.nls.json
index 2108ab2..eef1192 100644
--- a/package.nls.json
+++ b/package.nls.json
@@ -16,12 +16,13 @@
   "command.mcpp.languageServer.collectReport.title": "C++ Modules: Collect a Diagnostic Report",
   "command.mcpp.languageServer.exportDiagnosticBundle.title": "C++ Modules: Export a Diagnostic Bundle",
   "command.mcpp.languageServer.installTools.title": "C++ Modules: Install Command Line Tools",
-  "command.mcpp.languageServer.manageConflicts.title": "C++ Modules: Manage Other C++ Language Features",
+  "command.mcpp.languageServer.manageConflicts.title": "C++ Modules: Turn Off Other C++ Language Services",
   "command.mcpp.languageServer.openLogFolder.title": "Open the C++ Modules log folder",
   "command.mcpp.languageServer.refreshState.title": "C++ Modules: Refresh This View",
   "command.mcpp.languageServer.resetWorkspaceCache.title": "C++ Modules: Reset This Workspace's Cache",
   "command.mcpp.languageServer.restart.title": "C++ Modules: Restart the Language Server",
   "command.mcpp.languageServer.restartEngine.title": "C++ Modules: Restart the Semantic Engine",
+  "command.mcpp.languageServer.restoreConflicts.title": "C++ Modules: Restore Other C++ Language Services",
   "command.mcpp.languageServer.revealBundle.title": "Show the last diagnostic bundle",
   "command.mcpp.languageServer.reviewChanges.title": "C++ Modules: Review Workspace Changes",
   "command.mcpp.languageServer.runBuildToolInTerminal.title": "C++ Modules: Run the Build Tool in a Terminal",
diff --git a/package.nls.zh-cn.json b/package.nls.zh-cn.json
index 7236cee..33cc3ad 100644
--- a/package.nls.zh-cn.json
+++ b/package.nls.zh-cn.json
@@ -16,12 +16,13 @@
   "command.mcpp.languageServer.collectReport.title": "C++ Modules: 收集诊断报告",
   "command.mcpp.languageServer.exportDiagnosticBundle.title": "C++ Modules: 导出诊断包",
   "command.mcpp.languageServer.installTools.title": "C++ Modules: 安装命令行工具",
-  "command.mcpp.languageServer.manageConflicts.title": "C++ Modules: 处理其它 C++ 语言特性",
+  "command.mcpp.languageServer.manageConflicts.title": "C++ Modules: 关闭其他 C++ 语言服务",
   "command.mcpp.languageServer.openLogFolder.title": "打开 C++ Modules 日志目录",
   "command.mcpp.languageServer.refreshState.title": "C++ Modules: 刷新此视图",
   "command.mcpp.languageServer.resetWorkspaceCache.title": "C++ Modules: 重置本工作区缓存",
   "command.mcpp.languageServer.restart.title": "C++ Modules: 重启语言服务",
   "command.mcpp.languageServer.restartEngine.title": "C++ Modules: 重启语义引擎",
+  "command.mcpp.languageServer.restoreConflicts.title": "C++ Modules: 恢复其他 C++ 语言服务",
   "command.mcpp.languageServer.revealBundle.title": "显示最近一次诊断包",
   "command.mcpp.languageServer.reviewChanges.title": "C++ Modules: 审查工作区改动",
   "command.mcpp.languageServer.runBuildToolInTerminal.title": "C++ Modules: 在终端运行构建工具",
diff --git a/src/buildscript/analysis.ts b/src/buildscript/analysis.ts
index 4f4af8e..c2d15e2 100644
--- a/src/buildscript/analysis.ts
+++ b/src/buildscript/analysis.ts
@@ -411,9 +411,35 @@ function findActionBlocks(masked: readonly MaskedLine[]): ActionBlock[] {
  *
  * `lines` are the file's lines without their terminators (`text.split(/\r?\n/)`).
  */
+export interface AnalysisOptions {
+  /**
+   * Whether rule 1 (`unknownSymbol`) runs. Off while C++ Modules (mcppls) serves
+   * `build.mcpp`: it compiles the file against the modules it really imports,
+   * so its answer replaces this guess. Default on.
+   */
+  unknownSymbols?: boolean;
+}
+
+/**
+ * The namespaces under `mcpp::` that the file's own imports bring in:
+ * `import mcpp.rules.qt;` makes `mcpp::rules::…` a name this snapshot cannot
+ * judge, so rule 1 leaves it alone. Comments and strings are already masked.
+ */
+function importedNamespaces(masked: readonly MaskedLine[]): Set<string> {
+  const namespaces = new Set<string>();
+  const imported = /\bimport\s+mcpp\.([A-Za-z_][A-Za-z0-9_]*)/g;
+  for (const line of masked) {
+    for (let match = imported.exec(line.code); match !== null; match = imported.exec(line.code)) {
+      namespaces.add(match[1]);
+    }
+  }
+  return namespaces;
+}
+
 export function analyseBuildScript(
   lines: readonly string[],
   severity: Exclude<Severity, "off">,
+  options: AnalysisOptions = {},
 ): BuildScriptDiagnostic[] {
   const masked: MaskedLine[] = [];
   const state: ScanState = { blockComment: false, rawDelim: null };
@@ -433,11 +459,12 @@ export function analyseBuildScript(
     });
   };
 
-  // 1. `mcpp::<name>` that the engine does not have.
-  for (let i = 0; i < masked.length; i += 1) {
+  // 1. `mcpp::<name>` that the engine does not have, and no import of the file brings in.
+  const imported = options.unknownSymbols === false ? undefined : importedNamespaces(masked);
+  for (let i = 0; imported !== undefined && i < masked.length; i += 1) {
     const symbols = /\bmcpp::([A-Za-z_][A-Za-z0-9_]*)/g;
     for (let match = symbols.exec(masked[i].code); match !== null; match = symbols.exec(masked[i].code)) {
-      if (KNOWN_SYMBOLS.has(match[1])) {
+      if (KNOWN_SYMBOLS.has(match[1]) || imported.has(match[1])) {
         continue;
       }
       report(
diff --git a/src/buildscript/modules.ts b/src/buildscript/modules.ts
index d4f255f..a626743 100644
--- a/src/buildscript/modules.ts
+++ b/src/buildscript/modules.ts
@@ -2,9 +2,9 @@
  * The modules a `build.mcpp` can legitimately `import`, and a scanner that finds
  * the import sites in one.
  *
- * §3.2.2 of the plugin-optimisation plan: `build.mcpp` keeps its own
- * `mcpp-build` language id and the C++ language service never sees it, so this
- * extension is the only thing that can explain what an import means. The rule is
+ * Since 0.7.0 `build.mcpp` is a `cpp` document and C++ Modules (mcppls)
+ * compiles it as the build program it is; while it serves the file it explains
+ * the imports itself, and this table is used only when it does not. The rule is
  * absolute — **we never report "module not found"**. This module therefore only
  * *recognises*; it never validates, because a build program's imports are
  * resolved by mcpp's own module graph (`docs/specs/build-plugins.md` §9,
diff --git a/src/buildscript/providers.ts b/src/buildscript/providers.ts
index df1f428..0e63778 100644
--- a/src/buildscript/providers.ts
+++ b/src/buildscript/providers.ts
@@ -2,9 +2,11 @@
  * The one-line integration point for `build.mcpp` intelligence.
  *
  * `src/extension.ts` stays the only assembly point: it calls this function with
- * its real context and a severity reader, and gets completion, hover and
- * diagnostics for the `mcpp-build` language id in return. The severity reader is
- * the one switch `src/extension.ts` already owns; the four boolean switches
+ * its real context, a severity reader and a "does C++ Modules serve this
+ * file" reader, and gets completion, hover and diagnostics for `build.mcpp`
+ * in return. `build.mcpp` is an ordinary `cpp` document (C++ Modules compiles
+ * it like any other unit), so the providers register on the `cpp` language with
+ * a `build.mcpp` filename pattern. The severity reader is the one switch `src/extension.ts` already owns; the four boolean switches
  * (`mcpp.buildScript.{intelligence,diagnostics,snippets,imports.knownModules}`)
  * are resolved here through `settings.ts`, because that file is the only place
  * this extension can be told about them.
@@ -18,7 +20,12 @@
  * disappears, while hover keeps recognising `std`/`std.compat`/`mcpp.*` and
  * diagnostics never report any import as missing.
  *
- * This build registers no document-symbol provider for `mcpp-build`, so there is
+ * While C++ Modules serves the file, what it answers better is left to it: the
+ * `unknownSymbol` rule (it compiles the file against the modules it really
+ * imports) and the known-module completion and hover after `import`. The
+ * SPEC-007 rule checks and the snippets stay: no compiler says those.
+ *
+ * This build registers no document-symbol provider for `build.mcpp`, so there is
  * nothing there to suppress; if one is added it must consult `intelligence` too.
  *
  * Everything shown comes from `api.ts` (the generated snapshot), `modules.ts` or
@@ -40,7 +47,14 @@ import { snippetsForScope } from "./snippets";
 // here rather than injected.
 const vscodeApi = require("vscode") as typeof vscode;
 
-const LANGUAGE = "mcpp-build";
+const LANGUAGE = "cpp";
+const FILE_NAME = "build.mcpp";
+const SELECTOR: vscode.DocumentFilter = { language: LANGUAGE, pattern: `**/${FILE_NAME}` };
+
+/** `build.mcpp` by name, as a `cpp` document. */
+function isBuildScript(document: vscode.TextDocument): boolean {
+  return document.languageId === LANGUAGE && document.uri.path.split("/").pop() === FILE_NAME;
+}
 
 const VS_SEVERITY: Record<"error" | "warning" | "info", vscode.DiagnosticSeverity> = {
   error: vscodeApi.DiagnosticSeverity.Error,
@@ -51,8 +65,10 @@ const VS_SEVERITY: Record<"error" | "warning" | "info", vscode.DiagnosticSeverit
 function toVscodeDiagnostics(
   document: vscode.TextDocument,
   severity: "warning" | "info",
+  servedByMcppls: boolean,
 ): vscode.Diagnostic[] {
-  return analyseBuildScript(document.getText().split(/\r?\n/), severity).map((entry) => {
+  const options = { unknownSymbols: !servedByMcppls };
+  return analyseBuildScript(document.getText().split(/\r?\n/), severity, options).map((entry) => {
     const diagnostic = new vscodeApi.Diagnostic(
       // The analyser reports 1-based line/column; `vscode.Position` is 0-based.
       new vscodeApi.Range(
@@ -88,13 +104,14 @@ function markdown(lines: readonly string[]): vscode.MarkdownString {
 export function registerBuildScriptProviders(
   context: { subscriptions: { push(...items: unknown[]): unknown } },
   severity: () => "warning" | "info" | "off",
+  servedByMcppls: () => boolean,
 ): void {
-  const selector: vscode.DocumentSelector = { language: LANGUAGE };
-  const collection = vscodeApi.languages.createDiagnosticCollection(LANGUAGE);
+  const selector: vscode.DocumentSelector = SELECTOR;
+  const collection = vscodeApi.languages.createDiagnosticCollection("mcpp-build-script");
   const contributions = () => buildScriptContributions(read, severity);
 
   const refresh = (document: vscode.TextDocument): void => {
-    if (document.languageId !== LANGUAGE) {
+    if (!isBuildScript(document)) {
       return;
     }
     const { diagnosticSeverity } = contributions();
@@ -102,7 +119,12 @@ export function registerBuildScriptProviders(
       collection.delete(document.uri);
       return;
     }
-    collection.set(document.uri, toVscodeDiagnostics(document, diagnosticSeverity));
+    collection.set(document.uri, toVscodeDiagnostics(document, diagnosticSeverity, servedByMcppls()));
+  };
+  const refreshAll = (): void => {
+    for (const document of vscodeApi.workspace.textDocuments) {
+      refresh(document);
+    }
   };
 
   const completion = vscodeApi.languages.registerCompletionItemProvider(selector, {
@@ -116,8 +138,9 @@ export function registerBuildScriptProviders(
       const afterImport = /\b(?:export\s+)?import\s+([A-Za-z0-9_.]*)$/.exec(before);
       if (afterImport !== null) {
         // Only the *list* is optional. Recognition itself (`knownModule`, hover,
-        // the no-diagnostic rule) is unconditional.
-        if (!completesKnownModules) {
+        // the no-diagnostic rule) is unconditional. C++ Modules completes module
+        // names from what the build can really see, so it answers instead.
+        if (!completesKnownModules || servedByMcppls()) {
           return undefined;
         }
         return knownModules()
@@ -173,7 +196,8 @@ export function registerBuildScriptProviders(
       }
       const lines = document.getText().split(/\r?\n/);
 
-      for (const site of scanImports(lines)) {
+      // An import's hover is C++ Modules' while it serves the file.
+      for (const site of servedByMcppls() ? [] : scanImports(lines)) {
         if (
           site.line === position.line &&
           position.character >= site.startCharacter &&
@@ -213,9 +237,15 @@ export function registerBuildScriptProviders(
     vscodeApi.workspace.onDidOpenTextDocument(refresh),
     vscodeApi.workspace.onDidChangeTextDocument((event) => refresh(event.document)),
     vscodeApi.workspace.onDidCloseTextDocument((document) => collection.delete(document.uri)),
+    // Whether C++ Modules serves the file can change at any time: installed,
+    // enabled, or switched off for this workspace.
+    vscodeApi.extensions.onDidChange(refreshAll),
+    vscodeApi.workspace.onDidChangeConfiguration((event) => {
+      if (event.affectsConfiguration("mcppls.enable") || event.affectsConfiguration("mcpp.buildScript")) {
+        refreshAll();
+      }
+    }),
   ];
-  for (const document of vscodeApi.workspace.textDocuments) {
-    refresh(document);
-  }
+  refreshAll();
   context.subscriptions.push(...subscriptions);
 }
diff --git a/src/buildscript/settings.ts b/src/buildscript/settings.ts
index 86c095a..258cb91 100644
--- a/src/buildscript/settings.ts
+++ b/src/buildscript/settings.ts
@@ -28,7 +28,7 @@ export type DiagnosticSeveritySetting = Exclude<Severity, "error">;
  */
 export type SettingsReader = <T>(key: string) => T;
 
-/** What the `mcpp-build` providers contribute, given the current settings. */
+/** What the `build.mcpp` providers contribute, given the current settings. */
 export interface BuildScriptContributions {
   /** Completion and hover for `mcpp::` symbols and known module names. */
   intelligence: boolean;
diff --git a/src/commands/ids.ts b/src/commands/ids.ts
index fc08ce9..f0a5b12 100644
--- a/src/commands/ids.ts
+++ b/src/commands/ids.ts
@@ -49,7 +49,9 @@ export const LANGUAGE_SERVER_COMMANDS = {
   revealBundle: "mcpp.languageServer.revealBundle",
   openLogFolder: "mcpp.languageServer.openLogFolder",
   runBuildToolInTerminal: "mcpp.languageServer.runBuildToolInTerminal",
+  /** Turns the other C++ language services off (the id is from 0.6.0). */
   manageConflicts: "mcpp.languageServer.manageConflicts",
+  restoreConflicts: "mcpp.languageServer.restoreConflicts",
   toggleInWorkspace: "mcpp.languageServer.toggleInWorkspace",
   installTools: "mcpp.languageServer.installTools",
   reviewChanges: "mcpp.languageServer.reviewChanges",
diff --git a/src/extension.ts b/src/extension.ts
index db251be..f4ab0ec 100644
--- a/src/extension.ts
+++ b/src/extension.ts
@@ -19,6 +19,7 @@ import { describeState } from "./mcppls/state";
 import {
   languageServerEnabled,
   languageServerInstalled,
+  languageServerServes,
   languageServerVersion,
   readLanguageServerState,
 } from "./mcppls/stateSource";
@@ -423,7 +424,7 @@ export async function activate(extensionContext: vscode.ExtensionContext): Promi
       return "off";
     }
     return read<"warning" | "info" | "off">("mcpp.buildScript.diagnostics.severity");
-  });
+  }, languageServerServes);
 
   extensionContext.subscriptions.push(
     output,
diff --git a/src/mcppls/bridge.ts b/src/mcppls/bridge.ts
index 55a7738..8ff8369 100644
--- a/src/mcppls/bridge.ts
+++ b/src/mcppls/bridge.ts
@@ -99,7 +99,7 @@ export function createLanguageServerBridge(environment: CapabilityEnvironment):
     refreshLanguageServerAfterBuild,
     ...forwarded,
     // The two commands whose *argument* selects the direction.
-    manageConflicts: (restore = false) => invoke("manageConflicts", restore),
+    manageConflicts: (restore = false) => invoke(restore ? "restoreOtherCppFeatures" : "turnOffOtherCppFeatures"),
     toggleInWorkspace: (enable) => invoke("toggleInWorkspace", enable),
     reviewChanges: (clear = false) => invoke("review", clear),
   };
diff --git a/src/mcppls/contract.ts b/src/mcppls/contract.ts
index 67bbffa..923b682 100644
--- a/src/mcppls/contract.ts
+++ b/src/mcppls/contract.ts
@@ -172,15 +172,28 @@ export const CAPABILITIES: readonly Capability[] = [
     degradedHint: "Installed C++ Modules does not offer this action.",
     confirmHint: "The build tool runs in an integrated terminal, with its normal side effects.",
   },
+  // Two capabilities, not one with a candidate chain: a chain is for a renamed
+  // command, and "turn off" falling back to "restore" would do the opposite.
+  // `danger: "none"` because mcppls's own command asks where to act (this
+  // workspace or user settings) and does nothing when that question is closed;
+  // the settings it writes are the other extensions' own keys, never `mcppls.*`.
   {
-    key: "manageConflicts",
+    key: "turnOffOtherCppFeatures",
     kind: "forward",
-    title: "Manage other C++ language features",
-    commands: ["mcppls.turnOffOtherCppFeatures", "mcppls.restoreOtherCppFeatures"],
+    title: "Turn off other C++ language services",
+    commands: ["mcppls.turnOffOtherCppFeatures"],
     required: false,
-    danger: "confirm",
-    degradedHint: "Installed C++ Modules does not offer conflict handling.",
-    confirmHint: "This changes settings belonging to other C++ extensions, at their own keys. C++ Modules performs the change.",
+    danger: "none",
+    degradedHint: "Installed C++ Modules does not offer this; turn the other extension's language features off in its own settings.",
+  },
+  {
+    key: "restoreOtherCppFeatures",
+    kind: "forward",
+    title: "Restore other C++ language services",
+    commands: ["mcppls.restoreOtherCppFeatures"],
+    required: false,
+    danger: "none",
+    degradedHint: "Installed C++ Modules does not offer this; turn the other extension's language features on in its own settings.",
   },
   {
     key: "toggleInWorkspace",
diff --git a/src/mcppls/otherCppFeatures.ts b/src/mcppls/otherCppFeatures.ts
new file mode 100644
index 0000000..827b2e6
--- /dev/null
+++ b/src/mcppls/otherCppFeatures.ts
@@ -0,0 +1,107 @@
+/**
+ * Which other C++ language services are serving next to C++ Modules, normalised.
+ *
+ * Pure, like `./state.ts`: no `vscode`, nothing here throws. Two sources:
+ *
+ * - **mcppls's own answer** (0.0.16+): `otherCppFeatures()` on the object its
+ *   `activate()` returned. It uses the same candidate table and the same "is it
+ *   active" decision as mcppls's own turn-off command, and it knows whether that
+ *   command has something to restore. Preferred whenever it is there.
+ * - **A local, read-only fallback** for an older mcppls: the same three
+ *   candidates, read from the installed extensions and their settings. It can
+ *   never know what mcppls remembered, so `canRestore` is `false`.
+ *
+ * Either way this extension only *reads*. Turning a service off or restoring it
+ * is mcppls's command (`mcppls.turnOffOtherCppFeatures`, which asks where), and
+ * the settings it writes are the other extensions' own, never `mcppls.*`.
+ */
+
+export interface OtherCppService {
+  extensionId: string;
+  displayName: string;
+  /** `true` when a setting turns its language features off; `false` (ccls) means disabling the extension. */
+  settable: boolean;
+}
+
+export interface OtherCppFeatures {
+  active: OtherCppService[];
+  /** mcppls remembers settings it changed and can put them back. */
+  canRestore: boolean;
+  /** Who answered: mcppls itself, or this extension's local read. */
+  source: "mcppls" | "local";
+}
+
+/** A candidate the local read knows; `section`/`key`/`off` is how its language features are turned off. */
+interface Candidate {
+  extensionId: string;
+  displayName: string;
+  setting?: { section: string; key: string; off: unknown };
+}
+
+/** The same three mcppls checks (its `conflictCandidates.ts`), for when it cannot be asked. */
+export const OTHER_CPP_CANDIDATES: readonly Candidate[] = [
+  { extensionId: "ms-vscode.cpptools", displayName: "C/C++", setting: { section: "C_Cpp", key: "intelliSenseEngine", off: "disabled" } },
+  { extensionId: "llvm-vs-code-extensions.vscode-clangd", displayName: "clangd", setting: { section: "clangd", key: "enable", off: false } },
+  { extensionId: "ccls-project.ccls", displayName: "ccls" },
+];
+
+/** The settings whose change can make a candidate active or inactive. */
+export const OTHER_CPP_SETTINGS: readonly string[] = OTHER_CPP_CANDIDATES.flatMap((candidate) =>
+  candidate.setting === undefined ? [] : [`${candidate.setting.section}.${candidate.setting.key}`],
+);
+
+/**
+ * The local read. `installed` answers for installed *and enabled* extensions
+ * (`vscode.extensions.getExtension`); `value` is the effective setting.
+ */
+export function localOtherCppFeatures(
+  installed: (extensionId: string) => boolean,
+  value: (section: string, key: string) => unknown,
+): OtherCppFeatures {
+  const active = OTHER_CPP_CANDIDATES.filter(
+    (candidate) =>
+      installed(candidate.extensionId) &&
+      (candidate.setting === undefined || value(candidate.setting.section, candidate.setting.key) !== candidate.setting.off),
+  ).map((candidate) => ({
+    extensionId: candidate.extensionId,
+    displayName: candidate.displayName,
+    settable: candidate.setting !== undefined,
+  }));
+  return { active, canRestore: false, source: "local" };
+}
+
+function isRecord(value: unknown): value is Record<string, unknown> {
+  return typeof value === "object" && value !== null && !Array.isArray(value);
+}
+
+function service(value: unknown): OtherCppService | undefined {
+  if (!isRecord(value) || typeof value.extensionId !== "string" || value.extensionId.length === 0) {
+    return undefined;
+  }
+  return {
+    extensionId: value.extensionId,
+    displayName: typeof value.displayName === "string" && value.displayName.length > 0 ? value.displayName : value.extensionId,
+    settable: value.settable !== false,
+  };
+}
+
+/**
+ * mcppls's answer, or `undefined` when the object has no such function, it
+ * throws, or what it returns has the wrong shape — the caller then reads locally.
+ */
+export function otherCppFeaturesFromExports(exportsValue: unknown): OtherCppFeatures | undefined {
+  if (!isRecord(exportsValue) || typeof exportsValue.otherCppFeatures !== "function") {
+    return undefined;
+  }
+  let answer: unknown;
+  try {
+    answer = (exportsValue.otherCppFeatures as () => unknown).call(exportsValue);
+  } catch {
+    return undefined;
+  }
+  if (!isRecord(answer) || !Array.isArray(answer.active)) {
+    return undefined;
+  }
+  const active = answer.active.map(service).filter((entry): entry is OtherCppService => entry !== undefined);
+  return { active, canRestore: answer.canRestore === true, source: "mcppls" };
+}
diff --git a/src/mcppls/stateSource.ts b/src/mcppls/stateSource.ts
index a63e92d..7dd74b6 100644
--- a/src/mcppls/stateSource.ts
+++ b/src/mcppls/stateSource.ts
@@ -16,6 +16,7 @@ import * as vscode from "vscode";
 
 import { read } from "../config/access";
 import { MCPPLS_EXTENSION_ID } from "./contract";
+import { localOtherCppFeatures, otherCppFeaturesFromExports, type OtherCppFeatures } from "./otherCppFeatures";
 import { readStateFromExports, type McpplsStateView } from "./state";
 
 /** Why a state read did not happen. The view prints it verbatim. */
@@ -43,6 +44,15 @@ export function languageServerEnabled(): boolean {
   return vscode.workspace.getConfiguration("mcppls").get<boolean>("enable", true) !== false;
 }
 
+/**
+ * Whether C++ Modules serves this workspace's C++ files, `build.mcpp` included:
+ * installed and enabled in VS Code, and not switched off here (`mcppls.enable`).
+ * Read-only, like everything else in this file.
+ */
+export function languageServerServes(): boolean {
+  return languageServerInstalled() && languageServerEnabled();
+}
+
 export function readLanguageServerState(): McpplsStateView {
   const extension = dependency();
   const meta = {
@@ -69,3 +79,22 @@ export function readLanguageServerState(): McpplsStateView {
     };
   }
 }
+
+/**
+ * The other C++ language services serving next to C++ Modules: mcppls's own
+ * answer when it gives one (and reading its exports is allowed), else a local
+ * read-only look at the same three candidates.
+ */
+export function readOtherCppFeatures(): OtherCppFeatures {
+  const extension = dependency();
+  if (extension !== undefined && extension.isActive && read<boolean>("mcpp.languageService.readState") !== false) {
+    const answer = otherCppFeaturesFromExports(extension.exports);
+    if (answer !== undefined) {
+      return answer;
+    }
+  }
+  return localOtherCppFeatures(
+    (extensionId) => vscode.extensions.getExtension(extensionId) !== undefined,
+    (section, key) => vscode.workspace.getConfiguration(section).get(key),
+  );
+}
diff --git a/src/views/languageServerView.ts b/src/views/languageServerView.ts
index 6baa138..1ac83f3 100644
--- a/src/views/languageServerView.ts
+++ b/src/views/languageServerView.ts
@@ -36,7 +36,9 @@ import {
   languageServerInstalled,
   languageServerVersion,
   readLanguageServerState,
+  readOtherCppFeatures,
 } from "../mcppls/stateSource";
+import { OTHER_CPP_SETTINGS } from "../mcppls/otherCppFeatures";
 import { PollTimer } from "../mcppls/timers";
 import { refreshTimerDecision } from "../cache/cacheState";
 import type { LanguageServiceBlock } from "./models";
@@ -162,6 +164,7 @@ export function registerLanguageServerCommands(
       enabled: languageServerEnabled(),
       version: languageServerVersion(),
       state: readLanguageServerState(),
+      otherCppFeatures: languageServerInstalled() ? readOtherCppFeatures() : undefined,
     };
   };
 
@@ -279,7 +282,8 @@ export function registerLanguageServerCommands(
   // answer is the zip's path, and the caller has to keep it.
   forward(LANGUAGE_SERVER_COMMANDS.runBuildToolInTerminal, "runBuildTool");
   forward(LANGUAGE_SERVER_COMMANDS.installTools, "installTools");
-  forward(LANGUAGE_SERVER_COMMANDS.manageConflicts, "manageConflicts", () => [true]);
+  forward(LANGUAGE_SERVER_COMMANDS.manageConflicts, "turnOffOtherCppFeatures");
+  forward(LANGUAGE_SERVER_COMMANDS.restoreConflicts, "restoreOtherCppFeatures");
   forward(LANGUAGE_SERVER_COMMANDS.reviewChanges, "review", () => [false]);
   forward(LANGUAGE_SERVER_COMMANDS.toggleInWorkspace, "toggleInWorkspace", () => [!languageServerEnabled()]);
 
@@ -310,7 +314,9 @@ export function registerLanguageServerCommands(
       if (
         event.affectsConfiguration("mcppls.enable") ||
         event.affectsConfiguration("mcpp.views.languageServer") ||
-        event.affectsConfiguration("mcpp.languageService")
+        event.affectsConfiguration("mcpp.languageService") ||
+        // Another C++ service turned on or off, by mcppls's command or by hand.
+        OTHER_CPP_SETTINGS.some((setting) => event.affectsConfiguration(setting))
       ) {
         refresh();
         applyTimer();
diff --git a/src/views/models.ts b/src/views/models.ts
index 95028d1..e65c4ad 100644
--- a/src/views/models.ts
+++ b/src/views/models.ts
@@ -49,9 +49,9 @@ export interface TreeNode {
   /**
    * A `ThemeColor` id the icon is drawn in, e.g. `"charts.blue"`.
    *
-   * Only ids the colour registry always carries are used (`charts.*`), and a
-   * theme that omits one leaves the icon in the normal foreground colour rather
-   * than making the row unreadable — colour is a hint here, never the state.
+   * Only ids the colour registry always carries are used (`charts.*`,
+   * `disabledForeground`), and a theme that omits one leaves the icon in the
+   * normal foreground colour rather than making the row unreadable — colour is a hint here, never the state.
    */
   iconColor?: string;
   /** Consumed by `when` clauses in package.json for inline actions. */
@@ -526,6 +526,11 @@ export interface LanguageServiceBlock {
     state?: string;
     issues?: readonly LanguageServiceIssue[];
   };
+  /** Other C++ language services serving next to it (C/C++, clangd, ccls). */
+  otherCppFeatures?: {
+    active: readonly { extensionId: string; displayName: string; settable: boolean }[];
+    canRestore: boolean;
+  };
 }
 
 /** The provider line the block always carries, so "who owns this" stays answerable. */
@@ -818,6 +823,9 @@ function languageServiceChildren(block: LanguageServiceBlock): TreeNode[] {
       icon: "beaker",
     },
   ];
+  if (block.otherCppFeatures !== undefined) {
+    nodes.push(otherCppFeaturesNode(block.otherCppFeatures));
+  }
 
   (state?.issues ?? []).forEach((issue, index) => {
     nodes.push({
@@ -850,6 +858,38 @@ function languageServiceChildren(block: LanguageServiceBlock): TreeNode[] {
   return nodes;
 }
 
+/**
+ * 「其他 C++ 语言服务」: another service answering the same files shows every
+ * result twice, so while one is active the row says which and one click hands
+ * the decision to mcppls (`mcppls.turnOffOtherCppFeatures`, which asks where).
+ * With none, the row stays as a quiet, dimmed confirmation and does nothing.
+ * When mcppls remembers settings it changed, the row's context menu offers to
+ * put them back (`package.json`: `viewItem =~ /Restorable$/`).
+ */
+function otherCppFeaturesNode(features: NonNullable<LanguageServiceBlock["otherCppFeatures"]>): TreeNode {
+  const restorable = features.canRestore ? "Restorable" : "";
+  if (features.active.length === 0) {
+    return {
+      id: "project.languageService.otherCppFeatures",
+      label: plain("Only C++ Modules is serving C++"),
+      icon: "pass",
+      iconColor: "disabledForeground",
+      tooltip: plain("No other C++ language service (C/C++, clangd, ccls) is active, so no result is shown twice."),
+      contextValue: `mcppOtherCppFeatures${restorable}`,
+    };
+  }
+  const label = plain("Other C++ language services");
+  return {
+    id: "project.languageService.otherCppFeatures",
+    label,
+    description: { key: "{0}", args: [features.active.map((entry) => entry.displayName).join(", ")] },
+    icon: "warning",
+    tooltip: plain("They answer the same C++ files, so results appear twice. Click to turn their C++ language features off; C++ Modules asks whether for this workspace or everywhere."),
+    contextValue: `mcppOtherCppFeatures${restorable}`,
+    command: { command: "mcpp.languageServer.manageConflicts", title: label },
+  };
+}
+
 function actionNode(action: ActionRow): TreeNode {
   const label = plain(action.label);
   return {
diff --git a/syntaxes/mcpp-build-language-configuration.json b/syntaxes/mcpp-build-language-configuration.json
deleted file mode 100644
index b49c932..0000000
--- a/syntaxes/mcpp-build-language-configuration.json
+++ /dev/null
@@ -1,25 +0,0 @@
-{
-  "comments": {
-    "lineComment": "//",
-    "blockComment": ["/*", "*/"]
-  },
-  "brackets": [
-    ["{", "}"],
-    ["[", "]"],
-    ["(", ")"]
-  ],
-  "autoClosingPairs": [
-    {"open": "{", "close": "}"},
-    {"open": "[", "close": "]"},
-    {"open": "(", "close": ")"},
-    {"open": "\"", "close": "\""},
-    {"open": "'", "close": "'"}
-  ],
-  "surroundingPairs": [
-    ["{", "}"],
-    ["[", "]"],
-    ["(", ")"],
-    ["\"", "\""],
-    ["'", "'"]
-  ]
-}
diff --git a/syntaxes/mcpp-build.tmLanguage.json b/syntaxes/mcpp-build.tmLanguage.json
deleted file mode 100644
index 3635680..0000000
--- a/syntaxes/mcpp-build.tmLanguage.json
+++ /dev/null
@@ -1,10 +0,0 @@
-{
-  "$schema": "https://raw.githubusercontent.com/martinring/tmlanguage/master/tmlanguage.json",
-  "name": "mcpp build script",
-  "scopeName": "source.mcpp-build",
-  "patterns": [
-    {
-      "include": "source.cpp"
-    }
-  ]
-}
diff --git a/syntaxes/mcpp-modules.tmLanguage.json b/syntaxes/mcpp-modules.tmLanguage.json
index 28c69e3..39bd45d 100644
--- a/syntaxes/mcpp-modules.tmLanguage.json
+++ b/syntaxes/mcpp-modules.tmLanguage.json
@@ -2,7 +2,7 @@
   "$schema": "https://raw.githubusercontent.com/martinring/tmlanguage/master/tmlanguage.json",
   "name": "mcpp C++ Modules",
   "scopeName": "source.cpp.mcpp-modules",
-  "injectionSelector": "L:source.cpp, L:source.mcpp-build",
+  "injectionSelector": "L:source.cpp",
   "patterns": [
     {
       "include": "#module-declaration"
diff --git a/test/artifacts.test.ts b/test/artifacts.test.ts
index d710dbd..f3b39f3 100644
--- a/test/artifacts.test.ts
+++ b/test/artifacts.test.ts
@@ -1,5 +1,5 @@
 import assert from "node:assert/strict";
-import { readdirSync, readFileSync } from "node:fs";
+import { existsSync, readdirSync, readFileSync } from "node:fs";
 import path from "node:path";
 import test from "node:test";
 
@@ -68,7 +68,6 @@ test("declares mcpp-language-server as the C++ modules language service", () =>
   assert.deepEqual(manifest.activationEvents, [
     "workspaceContains:mcpp.toml",
     "onLanguage:mcpp-toml",
-    "onLanguage:mcpp-build",
   ]);
   assert.equal(manifest.capabilities?.untrustedWorkspaces?.supported, "limited");
   assert.equal(manifest.capabilities?.untrustedWorkspaces?.description, "%untrustedWorkspaces.description%");
@@ -348,31 +347,36 @@ test("shows editor title buttons only inside mcpp projects", () => {
   assert.ok(!commands.some((command) => command.command === "mcpp.inProject"));
 });
 
-test("ships syntax-only C++ highlighting for the exact build.mcpp filename", () => {
+test("build.mcpp is a cpp document, not a language of its own", () => {
   const manifest = JSON.parse(readFileSync(path.join(root, "package.json"), "utf8")) as PackageManifest;
   const associations = manifest.contributes?.configurationDefaults?.["files.associations"] as
     | Record<string, string>
     | undefined;
-  const language = manifest.contributes?.languages?.find((item) => item.id === "mcpp-build");
-  const grammar = manifest.contributes?.grammars?.find((item) => item.language === "mcpp-build");
-
+  // 0.6.0 claimed `build.mcpp` as `mcpp-build`. A filename match beats an
+  // extension match in VS Code, so that hid the file from C++ Modules (which
+  // selects `cpp`), and the build program got a text check instead of a compiler.
+  const languages = manifest.contributes?.languages ?? [];
+  assert.equal(languages.find((item) => item.id === "mcpp-build"), undefined);
+  assert.deepEqual(languages.find((item) => item.id === "cpp"), { id: "cpp", filenames: ["build.mcpp"] });
+  assert.equal(manifest.contributes?.grammars?.find((item) => item.language === "mcpp-build"), undefined);
   assert.equal(associations?.["build.mcpp"], undefined);
   assert.equal(associations?.["*.mcpp"], undefined);
-  assert.deepEqual(language, {
-    id: "mcpp-build",
-    aliases: ["mcpp build script", "build.mcpp"],
-    filenames: ["build.mcpp"],
-    configuration: "./syntaxes/mcpp-build-language-configuration.json",
-  });
-  assert.deepEqual(grammar, {
-    language: "mcpp-build",
-    scopeName: "source.mcpp-build",
-    path: "./syntaxes/mcpp-build.tmLanguage.json",
-  });
+  assert.ok(!existsSync(path.join(root, "syntaxes/mcpp-build.tmLanguage.json")));
+  assert.ok(!existsSync(path.join(root, "syntaxes/mcpp-build-language-configuration.json")));
+});
 
-  const grammarText = readFileSync(path.join(root, "syntaxes/mcpp-build.tmLanguage.json"), "utf8");
-  const grammarDocument = JSON.parse(grammarText) as { patterns?: Array<{ include?: string }> };
-  assert.ok(grammarDocument.patterns?.some((pattern) => pattern.include === "source.cpp"));
+test("restoring other C++ services is offered only on a row that says it can be", () => {
+  const manifest = JSON.parse(readFileSync(path.join(root, "package.json"), "utf8")) as {
+    contributes?: { menus?: Record<string, Array<{ command: string; when?: string }>> };
+  };
+  const entries = manifest.contributes?.menus?.["view/item/context"] ?? [];
+  const restore = entries.find((entry) => entry.command === "mcpp.languageServer.restoreConflicts");
+  assert.ok(restore?.when?.includes("view == mcpp.project"));
+  const pattern = /viewItem =~ \/(.*)\/$/.exec(restore?.when ?? "");
+  assert.ok(pattern, "the menu matches the row's contextValue");
+  const matches = new RegExp(pattern[1]);
+  assert.ok(matches.test("mcppOtherCppFeaturesRestorable"));
+  assert.ok(!matches.test("mcppOtherCppFeatures"));
 });
 
 test("ships TOML highlighting for the exact mcpp.toml filename", () => {
@@ -424,7 +428,7 @@ test("ships an injection grammar with module-specific scopes", () => {
   const grammar = manifest.contributes?.grammars?.find((item) => item.scopeName === "source.cpp.mcpp-modules");
   assert.deepEqual(grammar, {
     scopeName: "source.cpp.mcpp-modules",
-    injectTo: ["source.cpp", "source.mcpp-build"],
+    injectTo: ["source.cpp"],
     path: "./syntaxes/mcpp-modules.tmLanguage.json",
   });
 
@@ -433,7 +437,7 @@ test("ships an injection grammar with module-specific scopes", () => {
     injectionSelector?: string;
     repository?: Record<string, unknown>;
   };
-  assert.match(grammarDocument.injectionSelector ?? "", /source\.mcpp-build/);
+  assert.equal(grammarDocument.injectionSelector, "L:source.cpp");
   for (const key of ["module-declaration", "import-declaration", "module-name"]) {
     assert.ok(grammarDocument.repository?.[key], `missing grammar rule: ${key}`);
   }
diff --git a/test/buildscript/analysis.test.ts b/test/buildscript/analysis.test.ts
index ea3cb4b..96358cd 100644
--- a/test/buildscript/analysis.test.ts
+++ b/test/buildscript/analysis.test.ts
@@ -197,3 +197,37 @@ test("each rule id is the SPEC-007 code the plan names", () => {
     "mcpp.buildscript.actionNeedsRole",
   ]);
 });
+
+test("rule 1 leaves a namespace the file imports to the module that brings it", () => {
+  // The qt-demo shape: `import mcpp.rules.qt;` and then `mcpp::rules::qt::…`.
+  const lines = [
+    "import std;",
+    "import mcpp;",
+    "import mcpp.rules.qt;",
+    "",
+    "int main() {",
+    "    auto qt = mcpp::rules::qt::options{};",
+    "    mcpp::rules::qt::apply(qt);",
+    "    mcpp::nope();",
+    "}",
+  ];
+  assert.deepEqual(codes(lines), [DIAGNOSTIC_CODES.unknownSymbol]);
+  assert.match(analyseBuildScript(lines, "warning")[0].message, /mcpp::nope/);
+});
+
+test("rule 1 does not count an import that is commented out", () => {
+  const lines = ["// import mcpp.rules.qt;", "int main() { mcpp::rules::qt::apply(); }"];
+  assert.deepEqual(codes(lines), [DIAGNOSTIC_CODES.unknownSymbol]);
+});
+
+test("with rule 1 off, the SPEC-007 rule checks still run", () => {
+  const lines = [
+    "import mcpp;",
+    "int main() {",
+    "    mcpp::nope();",
+    '    mcpp::link_flag("-Wl,-rpath,/opt/lib");',
+    "}",
+  ];
+  const found = analyseBuildScript(lines, "warning", { unknownSymbols: false }).map((entry) => entry.code);
+  assert.deepEqual(found, [DIAGNOSTIC_CODES.rpathInLinkFlag]);
+});
diff --git a/test/commands/ids.test.ts b/test/commands/ids.test.ts
index eebe552..ed3713d 100644
--- a/test/commands/ids.test.ts
+++ b/test/commands/ids.test.ts
@@ -68,6 +68,7 @@ test("the C++ Modules group lists every id it registers", () => {
     "mcpp.languageServer.openLogFolder",
     "mcpp.languageServer.runBuildToolInTerminal",
     "mcpp.languageServer.manageConflicts",
+    "mcpp.languageServer.restoreConflicts",
     "mcpp.languageServer.toggleInWorkspace",
     "mcpp.languageServer.installTools",
     "mcpp.languageServer.reviewChanges",
diff --git a/test/e2e/fixtures/project/build.mcpp b/test/e2e/fixtures/project/build.mcpp
new file mode 100644
index 0000000..a2a79f8
--- /dev/null
+++ b/test/e2e/fixtures/project/build.mcpp
@@ -0,0 +1,9 @@
+import std;
+import mcpp;
+import mcpp.rules.qt;
+
+int main() {
+    auto qt = mcpp::rules::qt::options{};
+    mcpp::link_flag("-Wl,-rpath,/opt/lib");
+    return 0;
+}
diff --git a/test/e2e/runTest.ts b/test/e2e/runTest.ts
index fe0cae7..7c0596b 100644
--- a/test/e2e/runTest.ts
+++ b/test/e2e/runTest.ts
@@ -41,6 +41,7 @@ async function runVariant(repositoryRoot: string, fixtureRoot: string, variant:
   writeFileSync(join(mcpplsStub, "extension.js"), stubExtensionJs(variant));
   copyFileSync(join(fixtureRoot, "project/mcpp.toml"), join(workspaceDir, "mcpp.toml"));
   copyFileSync(join(fixtureRoot, "project/main.cpp"), join(workspaceDir, "main.cpp"));
+  copyFileSync(join(fixtureRoot, "project/build.mcpp"), join(workspaceDir, "build.mcpp"));
 
   // `MCPP_E2E_CODE` runs the suite against an already-installed VS Code, which is
   // what makes the Extension Host tests runnable without the 135 MB download.
diff --git a/test/e2e/suite/extension.e2e.ts b/test/e2e/suite/extension.e2e.ts
index 2dde6c1..481cd99 100644
--- a/test/e2e/suite/extension.e2e.ts
+++ b/test/e2e/suite/extension.e2e.ts
@@ -124,4 +124,24 @@ suite(`mcpp extension smoke (mcppls stub: ${STUB})`, () => {
   test("opening the settings panel does not throw", async () => {
     await vscode.commands.executeCommand("mcpp.openSettings");
   });
+
+  test("build.mcpp opens as cpp, and C++ Modules is left the names it answers", async () => {
+    const workspaceFolder = vscode.workspace.workspaceFolders?.[0];
+    assert.ok(workspaceFolder, "the fixture workspace should be open");
+    const uri = vscode.Uri.joinPath(workspaceFolder.uri, "build.mcpp");
+    const document = await vscode.workspace.openTextDocument(uri);
+    assert.equal(document.languageId, "cpp", "build.mcpp must reach the C++ language service");
+
+    // The stub is installed and enabled, so the rule checks run and `unknownSymbol` does not.
+    const deadline = Date.now() + 10_000;
+    let codes: string[] = [];
+    while (Date.now() < deadline) {
+      codes = vscode.languages.getDiagnostics(uri).map((diagnostic) => String(diagnostic.code));
+      if (codes.length > 0) {
+        break;
+      }
+      await new Promise((resolvePromise) => setTimeout(resolvePromise, 100));
+    }
+    assert.deepEqual(codes, ["mcpp.buildscript.rpathInLinkFlag"]);
+  });
 });
diff --git a/test/mcppls/bridge.test.ts b/test/mcppls/bridge.test.ts
index 20cbf54..f732696 100644
--- a/test/mcppls/bridge.test.ts
+++ b/test/mcppls/bridge.test.ts
@@ -133,13 +133,23 @@ test("coalesces concurrent build refresh requests into one call", async () => {
   assert.deepEqual(calls, ["mcppls.reloadBuildDescription"]);
 });
 
-test("directional commands pass their argument through", async () => {
+test("turning other C++ services off and restoring them are two commands, never one falling back to the other", async () => {
   const { bridge, calls } = harness();
+  await bridge.manageConflicts();
   await bridge.manageConflicts(true);
+  assert.deepEqual(calls, [
+    { command: "mcppls.turnOffOtherCppFeatures", args: [] },
+    { command: "mcppls.restoreOtherCppFeatures", args: [] },
+  ]);
+  assert.equal(bridge.dangerOf("turnOffOtherCppFeatures"), "none");
+  assert.equal(bridge.dangerOf("restoreOtherCppFeatures"), "none");
+});
+
+test("directional commands pass their argument through", async () => {
+  const { bridge, calls } = harness();
   await bridge.toggleInWorkspace(false);
   await bridge.reviewChanges(true);
   assert.deepEqual(calls, [
-    { command: "mcppls.turnOffOtherCppFeatures", args: [true] },
     { command: "mcppls.turnOffInWorkspace", args: [false] },
     { command: "mcppls.review.run", args: [true] },
   ]);
diff --git a/test/mcppls/otherCppFeatures.test.ts b/test/mcppls/otherCppFeatures.test.ts
new file mode 100644
index 0000000..8f18ecd
--- /dev/null
+++ b/test/mcppls/otherCppFeatures.test.ts
@@ -0,0 +1,69 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+
+import {
+  OTHER_CPP_SETTINGS,
+  localOtherCppFeatures,
+  otherCppFeaturesFromExports,
+} from "../../src/mcppls/otherCppFeatures";
+
+const installed = (...ids: string[]) => (id: string) => ids.includes(id);
+const settings = (values: Record<string, unknown>) => (section: string, key: string) => values[`${section}.${key}`];
+
+test("the local read finds each candidate that is installed and not turned off", () => {
+  const found = localOtherCppFeatures(
+    installed("ms-vscode.cpptools", "llvm-vs-code-extensions.vscode-clangd", "ccls-project.ccls"),
+    settings({ "C_Cpp.intelliSenseEngine": "default" }),
+  );
+  assert.deepEqual(found, {
+    active: [
+      { extensionId: "ms-vscode.cpptools", displayName: "C/C++", settable: true },
+      { extensionId: "llvm-vs-code-extensions.vscode-clangd", displayName: "clangd", settable: true },
+      { extensionId: "ccls-project.ccls", displayName: "ccls", settable: false },
+    ],
+    canRestore: false,
+    source: "local",
+  });
+});
+
+test("the local read leaves out what is turned off by its own setting, or not installed", () => {
+  const found = localOtherCppFeatures(
+    installed("ms-vscode.cpptools", "llvm-vs-code-extensions.vscode-clangd"),
+    settings({ "C_Cpp.intelliSenseEngine": "disabled", "clangd.enable": false }),
+  );
+  assert.deepEqual(found.active, []);
+  assert.deepEqual(OTHER_CPP_SETTINGS, ["C_Cpp.intelliSenseEngine", "clangd.enable"]);
+});
+
+test("mcppls's own answer is taken as it is, including whether it can restore", () => {
+  const exportsValue = {
+    otherCppFeatures: () => ({
+      active: [{ extensionId: "llvm-vs-code-extensions.vscode-clangd", displayName: "clangd", settable: true }],
+      canRestore: true,
+    }),
+  };
+  assert.deepEqual(otherCppFeaturesFromExports(exportsValue), {
+    active: [{ extensionId: "llvm-vs-code-extensions.vscode-clangd", displayName: "clangd", settable: true }],
+    canRestore: true,
+    source: "mcppls",
+  });
+});
+
+test("an older mcppls, a throwing one, or a malformed answer means the local read is used", () => {
+  assert.equal(otherCppFeaturesFromExports(undefined), undefined);
+  assert.equal(otherCppFeaturesFromExports({ lastStatus: () => undefined }), undefined);
+  assert.equal(
+    otherCppFeaturesFromExports({
+      otherCppFeatures: () => {
+        throw new Error("boom");
+      },
+    }),
+    undefined,
+  );
+  assert.equal(otherCppFeaturesFromExports({ otherCppFeatures: () => ({ active: "clangd" }) }), undefined);
+  // Entries without an id are dropped rather than rendered as blanks.
+  assert.deepEqual(
+    otherCppFeaturesFromExports({ otherCppFeatures: () => ({ active: [{}, { extensionId: "x.y" }] }) }),
+    { active: [{ extensionId: "x.y", displayName: "x.y", settable: true }], canRestore: false, source: "mcppls" },
+  );
+});
diff --git a/test/views/projectLayout.test.ts b/test/views/projectLayout.test.ts
index 546a81f..1c4378a 100644
--- a/test/views/projectLayout.test.ts
+++ b/test/views/projectLayout.test.ts
@@ -414,3 +414,47 @@ test("the standalone C++ Modules view is gone", () => {
   assert.doesNotMatch(source, /createTreeView/);
   assert.match(source, /export function registerLanguageServerCommands\(/);
 });
+
+test("other C++ language services: active ones are named and one click turns them off", () => {
+  const block: LanguageServiceBlock = {
+    ...HEALTHY,
+    otherCppFeatures: {
+      active: [
+        { extensionId: "ms-vscode.cpptools", displayName: "C/C++", settable: true },
+        { extensionId: "llvm-vs-code-extensions.vscode-clangd", displayName: "clangd", settable: true },
+      ],
+      canRestore: false,
+    },
+  };
+  const service = find(buildProjectTree({ root: "/w" }, { languageService: block }), "project.languageService");
+  // Right under the provider, so "who answers my C++ files" reads top to bottom.
+  assert.deepEqual(ids(service?.children ?? []).slice(0, 3), [
+    "project.languageService.status",
+    "project.languageService.provider",
+    "project.languageService.otherCppFeatures",
+  ]);
+  const row = find(service?.children ?? [], "project.languageService.otherCppFeatures");
+  assert.equal(text(row?.label), "Other C++ language services");
+  assert.equal(text(row?.description), "C/C++, clangd");
+  assert.equal(row?.icon, "warning");
+  assert.equal(row?.iconColor, undefined);
+  assert.equal(row?.command?.command, "mcpp.languageServer.manageConflicts");
+  assert.equal(row?.contextValue, "mcppOtherCppFeatures");
+});
+
+test("other C++ language services: with none, the row is a dimmed confirmation with nothing to click", () => {
+  const block: LanguageServiceBlock = { ...HEALTHY, otherCppFeatures: { active: [], canRestore: true } };
+  const service = find(buildProjectTree({ root: "/w" }, { languageService: block }), "project.languageService");
+  const row = find(service?.children ?? [], "project.languageService.otherCppFeatures");
+  assert.equal(text(row?.label), "Only C++ Modules is serving C++");
+  assert.equal(row?.icon, "pass");
+  assert.equal(row?.iconColor, "disabledForeground");
+  assert.equal(row?.command, undefined);
+  // What mcppls turned off can still be put back, from the row's context menu.
+  assert.equal(row?.contextValue, "mcppOtherCppFeaturesRestorable");
+});
+
+test("other C++ language services: no row when there is nothing to read", () => {
+  const service = find(buildProjectTree({ root: "/w" }, { languageService: HEALTHY }), "project.languageService");
+  assert.equal(find(service?.children ?? [], "project.languageService.otherCppFeatures"), undefined);
+});
diff --git a/tools/generate-toml-schema.mjs b/tools/generate-toml-schema.mjs
index ad402f7..bfd4167 100644
--- a/tools/generate-toml-schema.mjs
+++ b/tools/generate-toml-schema.mjs
@@ -12,6 +12,8 @@
 //                                       checks (`kKnownPackageKeys`, ...). A
 //                                       section mcpp stops accepting therefore
 //                                       disappears from the schema.
+//   modules/manifest/src/key_registry.cppm — the [build] keys, once the parser
+//                                       reads them from the registry.
 //   mcpp.toml                         — [package] version -> sourceVersion.
 //   git rev-parse --short HEAD        — sourceCommit (or "unknown").
 //
@@ -60,6 +62,7 @@ const DOC_BASE = "https://github.com/mcpp-community/mcpp/blob/main/docs/04-mcpp-
 const SPEC_FILE = "docs/specs/manifest-semantics.md";
 const FIELD_DOC_FILE = "docs/04-mcpp-toml.md";
 const PARSER_FILE = "modules/manifest/src/toml.cppm";
+const REGISTRY_FILE = "modules/manifest/src/key_registry.cppm";
 
 function fail(message) {
   process.stderr.write(`generate-toml-schema: ${message}\n`);
@@ -460,7 +463,15 @@ function extractStringArray(parserText, arrayName) {
   const block = new RegExp(
     `(?:static\\s+)?constexpr\\s+std::string_view\\s+${arrayName}\\s*\\[\\]\\s*=\\s*\\{([\\s\\S]*?)\\};`,
   ).exec(parserText);
-  if (!block) fail(`${PARSER_FILE}: key list ${arrayName}[] not found`);
+  if (!block) {
+    // mcpp 2026.10.11+ states the [build] keys once, in the key registry, and the
+    // parser reads them from there: `const auto kKnownBuildKeys = registry_keys("build");`.
+    const fromRegistry = new RegExp(
+      `\\b${arrayName}\\s*=\\s*registry_keys\\(\\s*"([^"]+)"\\s*\\)`,
+    ).exec(parserText);
+    if (!fromRegistry) fail(`${PARSER_FILE}: key list ${arrayName}[] not found`);
+    return registryKeys(fromRegistry[1]);
+  }
   const values = [];
   const literal = /"([^"]*)"/g;
   let match;
@@ -471,6 +482,22 @@ function extractStringArray(parserText, arrayName) {
   return values;
 }
 
+// The keys of one table in mcpp's key registry: every `{"<table>", "<key>", …}`
+// row of `kKeyRegistry`, the table-as-a-whole row (`""`) left out.
+function registryKeys(table) {
+  const text = readSource(REGISTRY_FILE);
+  const block = /kKeyRegistry\s*\[\]\s*=\s*\{([\s\S]*?)\n\};/.exec(text);
+  if (!block) fail(`${REGISTRY_FILE}: kKeyRegistry[] not found`);
+  const values = [];
+  const row = /\{\s*"([^"]*)"\s*,\s*"([^"]*)"/g;
+  let match;
+  while ((match = row.exec(block[1])) !== null) {
+    if (match[1] === table && match[2] !== "") values.push(match[2]);
+  }
+  if (values.length === 0) fail(`${REGISTRY_FILE}: no keys for table ${table}`);
+  return values;
+}
+
 // ─── assemble ───────────────────────────────────────────────────────────────
 
 function buildKey(section, key) {