diff --git a/Sources/OpenLessCore/LLMProviderRegistry.swift b/Sources/OpenLessCore/LLMProviderRegistry.swift
new file mode 100644
index 00000000..6c65d896
--- /dev/null
+++ b/Sources/OpenLessCore/LLMProviderRegistry.swift
@@ -0,0 +1,94 @@
+import Foundation
+
+/// LLM provider 预设注册表。
+///
+/// 集中维护"用户能开箱即用的供应商列表"——豆包(Ark)、OpenAI、阿里通义 DashScope、
+/// DeepSeek、Moonshot——以及 baseURL / model / 帮助文案。UI 层用它生成添加 provider
+/// 的下拉菜单与帮助提示，运行期则用它兜底未填写的 baseURL / displayName。
+///
+/// `customProviderId` 是占位常量，不是真正的"id"：用户在添加自定义 provider 时由 UI 收集
+/// 一个 slug 写入 schema；这里仅用来在添加 sheet 中区分"预设 vs 自定义"。
+public enum LLMProviderRegistry {
+    /// 单条预设记录。
+    public struct Preset: Sendable, Hashable {
+        public let providerId: String
+        public let displayName: String
+        public let defaultBaseURL: URL
+        /// 预设的默认 model。Ark 故意留空——endpoint id 必须由用户在控制台拿到再填。
+        public let defaultModel: String
+        /// "怎么拿到 API Key" 的提示文案，UI 在帮助 disclosure 里展示。
+        public let helpText: String
+        /// 供应商 API Key 页面（可选）。UI 给一个"打开"按钮。
+        public let docsURL: URL?
+
+        public init(
+            providerId: String,
+            displayName: String,
+            defaultBaseURL: URL,
+            defaultModel: String,
+            helpText: String,
+            docsURL: URL?
+        ) {
+            self.providerId = providerId
+            self.displayName = displayName
+            self.defaultBaseURL = defaultBaseURL
+            self.defaultModel = defaultModel
+            self.helpText = helpText
+            self.docsURL = docsURL
+        }
+    }
+
+    /// 5 家 OpenAI 兼容供应商的开箱即用预设。
+    /// 顺序即为 UI 添加菜单里的展示顺序——第一个是 Ark（老用户迁移过来的默认）。
+    public static let presets: [Preset] = [
+        Preset(
+            providerId: "ark",
+            displayName: "豆包 (Ark)",
+            defaultBaseURL: URL(string: "https://ark.cn-beijing.volces.com/api/v3")!,
+            defaultModel: "",
+            helpText: "在火山引擎方舟控制台创建 endpoint 并把 endpoint id 填到 Model；API Key 在「我的 API Key」页生成。",
+            docsURL: URL(string: "https://www.volcengine.com/docs/82379/1099475")
+        ),
+        Preset(
+            providerId: "openai",
+            displayName: "OpenAI",
+            defaultBaseURL: URL(string: "https://api.openai.com/v1")!,
+            defaultModel: "gpt-4o-mini",
+            helpText: "platform.openai.com 创建 API key；推荐 gpt-4o-mini（性价比）或 gpt-4o（高质量）。需国外网络。",
+            docsURL: URL(string: "https://platform.openai.com/api-keys")
+        ),
+        Preset(
+            providerId: "aliyun-dashscope",
+            displayName: "阿里通义 (DashScope)",
+            defaultBaseURL: URL(string: "https://dashscope.aliyuncs.com/compatible-mode/v1")!,
+            defaultModel: "qwen-turbo",
+            helpText: "百炼控制台「API-KEY 管理」生成 sk-...；推荐 qwen-turbo（快）或 qwen-plus（强）。",
+            docsURL: URL(string: "https://help.aliyun.com/zh/model-studio/get-api-key")
+        ),
+        Preset(
+            providerId: "deepseek",
+            displayName: "DeepSeek",
+            defaultBaseURL: URL(string: "https://api.deepseek.com/v1")!,
+            defaultModel: "deepseek-chat",
+            helpText: "platform.deepseek.com 创建 API key；推荐 deepseek-chat。",
+            docsURL: URL(string: "https://platform.deepseek.com/api_keys")
+        ),
+        Preset(
+            providerId: "moonshot",
+            displayName: "Moonshot 月之暗面",
+            defaultBaseURL: URL(string: "https://api.moonshot.cn/v1")!,
+            defaultModel: "moonshot-v1-8k",
+            helpText: "platform.moonshot.cn 创建 API key；推荐 moonshot-v1-8k（短）或 moonshot-v1-32k（长）。",
+            docsURL: URL(string: "https://platform.moonshot.cn/console/api-keys")
+        ),
+    ]
+
+    /// 自定义 provider 的占位 id（不是真实 providerId，仅用于 UI 添加菜单）。
+    public static let customProviderId = "custom"
+    public static let customDisplayName = "自定义 OpenAI 兼容"
+
+    /// 根据 providerId 查预设；未知 id 返回 nil（自定义 provider 通常落到这里）。
+    public static func preset(for providerId: String) -> Preset? {
+        presets.first { $0.providerId == providerId }
+    }
+}
diff --git a/Sources/OpenLessPersistence/CredentialsError.swift b/Sources/OpenLessPersistence/CredentialsError.swift
index f12a2746..6069f41a 100644
--- a/Sources/OpenLessPersistence/CredentialsError.swift
+++ b/Sources/OpenLessPersistence/CredentialsError.swift
@@ -18,4 +18,8 @@ public enum CredentialsError: Error, Sendable, Equatable {
 
     /// 写入 v1 文件失败。携带目标 URL 和失败描述。
     case writeFailed(URL, String)
+
+    /// 试图删除当前 active 的 LLM provider。携带 providerId。
+    /// 调用方必须先把 active 切到别的 provider 再调 `removeLLMProvider`。
+    case cannotRemoveActiveProvider(String)
 }
diff --git a/Sources/OpenLessPersistence/CredentialsSchemaV1.swift b/Sources/OpenLessPersistence/CredentialsSchemaV1.swift
index 64cd2803..c3503858 100644
--- a/Sources/OpenLessPersistence/CredentialsSchemaV1.swift
+++ b/Sources/OpenLessPersistence/CredentialsSchemaV1.swift
@@ -34,12 +34,13 @@ public struct CredentialsSchemaV1: Codable, Sendable, Equatable {
 public struct CredentialsProviders: Codable, Sendable, Equatable {
     /// ASR 类别：providerId → provider 配置。M1 仅有 `volcengine`。
     public var asr: [String: CredentialsProviderASRVolcengine]
-    /// LLM 类别：providerId → provider 配置。M1 仅有 `ark`。
-    public var llm: [String: CredentialsProviderLLMArk]
+    /// LLM 类别：providerId → provider 配置。
+    /// 任意 OpenAI 兼容供应商（ark / openai / aliyun-dashscope / deepseek / moonshot / 自定义）共用一份 entry。
+    public var llm: [String: CredentialsProviderLLMEntry]
 
     public init(
         asr: [String: CredentialsProviderASRVolcengine] = [:],
-        llm: [String: CredentialsProviderLLMArk] = [:]
+        llm: [String: CredentialsProviderLLMEntry] = [:]
     ) {
         self.asr = asr
         self.llm = llm
@@ -84,44 +85,80 @@ public struct CredentialsProviderASRVolcengine: Codable, Sendable, Equatable {
     }
 }
 
-/// Ark (Doubao) chat-completions 凭据。
+/// 通用 OpenAI 兼容 LLM provider 凭据条目。
 ///
-/// 自定义编码：nil 字段直接省略。
-public struct CredentialsProviderLLMArk: Codable, Sendable, Equatable {
+/// 同一份结构覆盖 Ark / OpenAI / DashScope / DeepSeek / Moonshot 以及用户自定义条目；
+/// 需要呈现给 UI 的"友好名"放在 `displayName`（自定义时由用户指定，预设条目可缺省让 UI 兜底）。
+///
+/// 自定义编码：nil 字段直接省略；空 dict 的 `extraHeaders` 同样省略，保持 JSON 干净。
+public struct CredentialsProviderLLMEntry: Codable, Sendable, Equatable, Hashable {
+    /// 用户给该条目设置的展示名（自定义条目必填；预设条目允许 nil 由 UI 用 registry 兜底）。
+    public var displayName: String?
     public var apiKey: String?
+    /// 字符串而不是 URL：编辑过程中用户输入可能是非法 URL，schema 不在这里早 fail。
     public var baseURL: String?
     public var model: String?
+    /// 该 provider 的 temperature 覆盖；为空时使用 `OpenAICompatibleConfig` 的默认值。
+    public var temperature: Double?
+    public var extraHeaders: [String: String]?
 
-    public init(apiKey: String? = nil, baseURL: String? = nil, model: String? = nil) {
+    public init(
+        displayName: String? = nil,
+        apiKey: String? = nil,
+        baseURL: String? = nil,
+        model: String? = nil,
+        temperature: Double? = nil,
+        extraHeaders: [String: String]? = nil
+    ) {
+        self.displayName = displayName
         self.apiKey = apiKey
         self.baseURL = baseURL
         self.model = model
+        self.temperature = temperature
+        self.extraHeaders = extraHeaders
     }
 
     /// 是否所有字段都是空 / nil。
     public var isAllEmpty: Bool {
-        isNilOrEmpty(apiKey) && isNilOrEmpty(baseURL) && isNilOrEmpty(model)
+        isNilOrEmpty(displayName)
+            && isNilOrEmpty(apiKey)
+            && isNilOrEmpty(baseURL)
+            && isNilOrEmpty(model)
+            && temperature == nil
+            && (extraHeaders?.isEmpty ?? true)
     }
 
     private enum CodingKeys: String, CodingKey {
-        case apiKey, baseURL, model
+        case displayName, apiKey, baseURL, model, temperature, extraHeaders
     }
 
     public func encode(to encoder: Encoder) throws {
         var c = encoder.container(keyedBy: CodingKeys.self)
+        try c.encodeIfPresent(displayName, forKey: .displayName)
         try c.encodeIfPresent(apiKey, forKey: .apiKey)
         try c.encodeIfPresent(baseURL, forKey: .baseURL)
         try c.encodeIfPresent(model, forKey: .model)
+        try c.encodeIfPresent(temperature, forKey: .temperature)
+        if let headers = extraHeaders, !headers.isEmpty {
+            try c.encode(headers, forKey: .extraHeaders)
+        }
     }
 
     public init(from decoder: Decoder) throws {
         let c = try decoder.container(keyedBy: CodingKeys.self)
+        displayName = try c.decodeIfPresent(String.self, forKey: .displayName)
         apiKey = try c.decodeIfPresent(String.self, forKey: .apiKey)
         baseURL = try c.decodeIfPresent(String.self, forKey: .baseURL)
         model = try c.decodeIfPresent(String.self, forKey: .model)
+        temperature = try c.decodeIfPresent(Double.self, forKey: .temperature)
+        extraHeaders = try c.decodeIfPresent([String: String].self, forKey: .extraHeaders)
     }
 }
 
+/// 兼容别名：B-2 时期叫 `CredentialsProviderLLMArk`。
+/// 通用化后所有 LLM provider 共用同一类型。保留 typealias 让外部代码继续编译。
+public typealias CredentialsProviderLLMArk = CredentialsProviderLLMEntry
+
 // MARK: - Active selection
 
 /// 当前激活的 provider。M1 默认 `volcengine` / `ark`。
diff --git a/Sources/OpenLessPersistence/CredentialsVault.swift b/Sources/OpenLessPersistence/CredentialsVault.swift
index 9f511bb8..b5898882 100644
--- a/Sources/OpenLessPersistence/CredentialsVault.swift
+++ b/Sources/OpenLessPersistence/CredentialsVault.swift
@@ -1,4 +1,5 @@
 import Foundation
+import OpenLessCore
 
 /// 开发期凭据存储：JSON 文件，路径 `~/.openless/credentials.json`，权限 0600。
 ///
@@ -81,19 +82,20 @@ public final class CredentialsVault: @unchecked Sendable {
     }
 
     /// 一次性把所有账号读出来；调用方在内存里持有，避免每次会话都打 IO。
+    /// snapshot 跟随当前 active provider；切换 active LLM 后再次调用会反映新的 provider 字段。
     public func snapshot() -> CredentialsSnapshot {
         lock.lock()
         defer { lock.unlock() }
         loadIfNeededLocked()
-        let volc = schema.providers.asr[defaultActiveASRProviderId]
-        let ark = schema.providers.llm[defaultActiveLLMProviderId]
+        let volc = schema.providers.asr[schema.active.asr]
+        let llm = schema.providers.llm[schema.active.llm]
         return CredentialsSnapshot(
             volcengineAppKey: volc?.appKey,
             volcengineAccessKey: volc?.accessKey,
             volcengineResourceId: volc?.resourceId,
-            arkApiKey: ark?.apiKey,
-            arkModelId: ark?.model,
-            arkEndpoint: ark?.baseURL
+            arkApiKey: llm?.apiKey,
+            arkModelId: llm?.model,
+            arkEndpoint: llm?.baseURL
         )
     }
 
@@ -261,19 +263,24 @@ public final class CredentialsVault: @unchecked Sendable {
     // MARK: - 账号 key → v1 字段路由
 
     private func readAccountLocked(_ account: String) -> String? {
+        // ASR 路径锁定到 active ASR provider；LLM 路径锁定到 active LLM provider。
+        // 一旦用户在 LLM 设置页切换 active（比如从 ark 切到 deepseek），老 UI 通过
+        // `ark.*` 账号 key 看到的就是 deepseek 的字段——这是预期行为。
+        let activeASR = schema.active.asr
+        let activeLLM = schema.active.llm
         switch account {
         case CredentialAccount.volcengineAppKey:
-            return schema.providers.asr[defaultActiveASRProviderId]?.appKey
+            return schema.providers.asr[activeASR]?.appKey
         case CredentialAccount.volcengineAccessKey:
-            return schema.providers.asr[defaultActiveASRProviderId]?.accessKey
+            return schema.providers.asr[activeASR]?.accessKey
         case CredentialAccount.volcengineResourceId:
-            return schema.providers.asr[defaultActiveASRProviderId]?.resourceId
+            return schema.providers.asr[activeASR]?.resourceId
         case CredentialAccount.arkApiKey:
-            return schema.providers.llm[defaultActiveLLMProviderId]?.apiKey
+            return schema.providers.llm[activeLLM]?.apiKey
         case CredentialAccount.arkModelId:
-            return schema.providers.llm[defaultActiveLLMProviderId]?.model
+            return schema.providers.llm[activeLLM]?.model
         case CredentialAccount.arkEndpoint:
-            return schema.providers.llm[defaultActiveLLMProviderId]?.baseURL
+            return schema.providers.llm[activeLLM]?.baseURL
         default:
             return nil
         }
@@ -319,26 +326,179 @@ public final class CredentialsVault: @unchecked Sendable {
     }
 
     private func mutateVolc(_ apply: (inout CredentialsProviderASRVolcengine) -> Void) {
-        var existing = schema.providers.asr[defaultActiveASRProviderId] ?? CredentialsProviderASRVolcengine()
+        // 老路径：`volcengine.*` 账号 key 始终路由到 active ASR provider。
+        // M1 active.asr 永远是 "volcengine"，未来加供应商时这里也无需再改。
+        let key = schema.active.asr
+        var existing = schema.providers.asr[key] ?? CredentialsProviderASRVolcengine()
         apply(&existing)
         if existing.isAllEmpty {
-            schema.providers.asr.removeValue(forKey: defaultActiveASRProviderId)
+            schema.providers.asr.removeValue(forKey: key)
         } else {
-            schema.providers.asr[defaultActiveASRProviderId] = existing
+            schema.providers.asr[key] = existing
         }
     }
 
-    private func mutateArk(_ apply: (inout CredentialsProviderLLMArk) -> Void) {
-        var existing = schema.providers.llm[defaultActiveLLMProviderId] ?? CredentialsProviderLLMArk()
+    private func mutateArk(_ apply: (inout CredentialsProviderLLMEntry) -> Void) {
+        // 老路径：`ark.*` 账号 key 始终路由到 active LLM provider。
+        // 这让 SettingsHubTab 等老 UI 在新 schema 下保持原本的"豆包"语义。
+        let key = schema.active.llm
+        var existing = schema.providers.llm[key] ?? CredentialsProviderLLMEntry()
         apply(&existing)
         if existing.isAllEmpty {
-            schema.providers.llm.removeValue(forKey: defaultActiveLLMProviderId)
+            schema.providers.llm.removeValue(forKey: key)
         } else {
-            schema.providers.llm[defaultActiveLLMProviderId] = existing
+            schema.providers.llm[key] = existing
         }
     }
 }
 
+// MARK: - 多 LLM provider 支持（B-3）
+
+extension CredentialsVault {
+    /// 当前选中的 LLM provider id；getter 同时承担"loadIfNeeded"。
+    public var activeLLMProviderId: String {
+        get {
+            lock.lock()
+            defer { lock.unlock() }
+            loadIfNeededLocked()
+            return schema.active.llm
+        }
+        set {
+            lock.lock()
+            defer { lock.unlock() }
+            loadIfNeededLocked()
+            guard schema.active.llm != newValue else { return }
+            schema.active.llm = newValue
+            try? writeLocked()
+        }
+    }
+
+    /// 列出所有已配置的 LLM provider id（包含还没填 apiKey 的占位条目）。
+    /// 用于设置页的 picker；当前 active 即便条目不存在也会被列出，避免"切换-删除"流程把用户卡死。
+    public var configuredLLMProviderIds: [String] {
+        lock.lock()
+        defer { lock.unlock() }
+        loadIfNeededLocked()
+        var ids = Set(schema.providers.llm.keys)
+        ids.insert(schema.active.llm)
+        return ids.sorted()
+    }
+
+    /// 读出某个 provider 的完整 OpenAICompatibleConfig；缺 apiKey 也仍然返回（让 UI 显示空表单）。
+    /// baseURL / displayName 缺省时用 registry 兜底；都没兜底则返回 nil。
+    public func llmProviderConfig(for providerId: String) -> OpenAICompatibleConfig? {
+        lock.lock()
+        defer { lock.unlock() }
+        loadIfNeededLocked()
+        let entry = schema.providers.llm[providerId]
+        let preset = LLMProviderRegistry.preset(for: providerId)
+
+        let displayName: String
+        if let stored = entry?.displayName, !stored.isEmpty {
+            displayName = stored
+        } else if let preset {
+            displayName = preset.displayName
+        } else {
+            displayName = providerId
+        }
+
+        let baseURL: URL
+        if let stored = entry?.baseURL,
+           !stored.isEmpty,
+           let parsed = URL(string: stored.trimmingCharacters(in: .whitespacesAndNewlines)) {
+            baseURL = parsed
+        } else if let preset {
+            baseURL = preset.defaultBaseURL
+        } else {
+            // 自定义 provider 又没填 baseURL：无法构造 config。
+            return nil
+        }
+
+        let model = entry?.model ?? preset?.defaultModel ?? ""
+        let apiKey = entry?.apiKey ?? ""
+        let temperature = entry?.temperature ?? 0.3
+        let extraHeaders = entry?.extraHeaders ?? [:]
+
+        return OpenAICompatibleConfig(
+            providerId: providerId,
+            displayName: displayName,
+            baseURL: baseURL,
+            apiKey: apiKey,
+            model: model,
+            extraHeaders: extraHeaders,
+            temperature: temperature
+        )
+    }
+
+    /// 写一份完整的 OpenAICompatibleConfig 到对应 provider id 下。
+    /// - 预设 provider：与 registry 默认值相同的 baseURL / displayName 不写盘（保持 JSON 简洁，
+    ///   未来 registry 调整时不会被旧文件锁死）。
+    /// - 自定义 provider：所有字段都写入（包括 displayName，因为没有 registry 可以兜底）。
+    public func setLLMProviderConfig(_ config: OpenAICompatibleConfig) {
+        lock.lock()
+        defer { lock.unlock() }
+        loadIfNeededLocked()
+
+        let preset = LLMProviderRegistry.preset(for: config.providerId)
+        var entry = schema.providers.llm[config.providerId] ?? CredentialsProviderLLMEntry()
+
+        // displayName：与 preset 相同就不写，UI 始终从 registry 拿。
+        if let preset, preset.displayName == config.displayName {
+            entry.displayName = nil
+        } else {
+            let trimmed = config.displayName.trimmingCharacters(in: .whitespacesAndNewlines)
+            entry.displayName = trimmed.isEmpty ? nil : trimmed
+        }
+
+        // baseURL：与 preset.defaultBaseURL 相同就不写。
+        if let preset, preset.defaultBaseURL == config.baseURL {
+            entry.baseURL = nil
+        } else {
+            entry.baseURL = config.baseURL.absoluteString
+        }
+
+        // model：与 preset.defaultModel 相同 / 为空 → 视为"未覆盖"，不写盘。
+        if let preset, !preset.defaultModel.isEmpty, preset.defaultModel == config.model {
+            entry.model = nil
+        } else {
+            let trimmed = config.model.trimmingCharacters(in: .whitespacesAndNewlines)
+            entry.model = trimmed.isEmpty ? nil : trimmed
+        }
+
+        // apiKey：空字符串 → nil，避免落出 `"apiKey": ""`。
+        let trimmedKey = config.apiKey.trimmingCharacters(in: .whitespacesAndNewlines)
+        entry.apiKey = trimmedKey.isEmpty ? nil : trimmedKey
+
+        // temperature：默认 0.3 视为未覆盖。
+        entry.temperature = config.temperature == 0.3 ? nil : config.temperature
+
+        // extraHeaders：空 dict 收敛成 nil。
+        entry.extraHeaders = config.extraHeaders.isEmpty ? nil : config.extraHeaders
+
+        if entry.isAllEmpty {
+            schema.providers.llm.removeValue(forKey: config.providerId)
+        } else {
+            schema.providers.llm[config.providerId] = entry
+        }
+        try? writeLocked()
+    }
+
+    /// 删除某个 LLM provider；不允许删 active provider。
+    /// 需要先把 `activeLLMProviderId` 切到别的 id，再删旧条目。
+    public func removeLLMProvider(_ providerId: String) throws {
+        lock.lock()
+        defer { lock.unlock() }
+        loadIfNeededLocked()
+
+        if schema.active.llm == providerId {
+            throw CredentialsError.cannotRemoveActiveProvider(providerId)
+        }
+        guard schema.providers.llm[providerId] != nil else { return }
+        schema.providers.llm.removeValue(forKey: providerId)
+        try writeLocked()
+    }
+}
+
 // MARK: - 时间戳工具
 
 /// 紧凑 ISO8601 时间戳，例如 `20260429T103045`。固定 UTC，避免 DST。
diff --git a/Sources/OpenLessPolish/DoubaoPolishClient.swift b/Sources/OpenLessPolish/DoubaoPolishClient.swift
deleted file mode 100644
index c638b35c..00000000
--- a/Sources/OpenLessPolish/DoubaoPolishClient.swift
+++ /dev/null
@@ -1,137 +0,0 @@
-import Foundation
-import OpenLessCore
-
-public enum PolishError: Error, Sendable {
-    case credentialsMissing
-    case requestFailed(String)
-    case decodeFailed
-    case modelReturnedEmpty
-}
-
-@available(*, deprecated, message: "Use OpenAICompatibleLLMProvider with Ark config; this class will be removed after the provider migration ships.")
-public final class DoubaoPolishClient: @unchecked Sendable {
-    private let credentials: ArkCredentials
-    private let logger: (@Sendable (String) -> Void)?
-    private let session: URLSession
-
-    public init(
-        credentials: ArkCredentials,
-        logger: (@Sendable (String) -> Void)? = nil,
-        session: URLSession = .shared
-    ) {
-        self.credentials = credentials
-        self.logger = logger
-        self.session = session
-    }
-
-    public func polish(
-        rawTranscript: RawTranscript,
-        mode: PolishMode,
-        referenceExamples: [PolishReferenceExample] = [],
-        dictionaryEntries: [DictionaryEntry] = []
-    ) async throws -> FinalText {
-        guard !rawTranscript.text.isEmpty else {
-            return FinalText(text: "", mode: mode)
-        }
-
-        var request = URLRequest(url: Self.chatCompletionsURL(from: credentials.endpoint))
-        request.httpMethod = "POST"
-        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
-        request.setValue("Bearer \(credentials.apiKey)", forHTTPHeaderField: "Authorization")
-        // 之前 30s 太短：DeepSeek V3.2 / R1 等模型即使关思考首 token 也可能 5-10s。
-        // 改成 10 分钟，等同"无上限"——polish 本身一定不会真挂这么久。
-        request.timeoutInterval = 600
-
-        let body: [String: Any] = [
-            "model": credentials.modelId,
-            "stream": false,
-            "temperature": 0.3,
-            // 关掉深度思考：V3.2 / R1 / Doubao Thinking 等模型默认会先生成一段"思考过程"
-            // 再给最终答案，对"整理一段口语"这种短任务是浪费——延迟 + 成本都翻几倍。
-            // 不支持 thinking 字段的模型（如 Doubao 普通版）会忽略这个参数。
-            "thinking": ["type": "disabled"],
-            "messages": [
-                ["role": "system", "content": PolishPrompts.systemPrompt(for: mode)],
-                ["role": "user", "content": PolishPrompts.userPrompt(
-                    for: rawTranscript.text,
-                    referenceExamples: referenceExamples,
-                    dictionaryEntries: dictionaryEntries
-                )],
-            ],
-        ]
-        request.httpBody = try JSONSerialization.data(withJSONObject: body)
-
-        if let httpBody = request.httpBody, let bodyStr = String(data: httpBody, encoding: .utf8) {
-            logger?("[polish] request body: \(bodyStr.prefix(500))")
-        }
-
-        let (data, response) = try await session.data(for: request)
-        guard let http = response as? HTTPURLResponse else {
-            throw PolishError.requestFailed("not http")
-        }
-        let respPreview = String(data: data, encoding: .utf8) ?? "<no body>"
-        logger?("[polish] HTTP \(http.statusCode) response: \(respPreview.prefix(500))")
-        guard (200..<300).contains(http.statusCode) else {
-            throw PolishError.requestFailed("HTTP \(http.statusCode): \(respPreview.prefix(300))")
-        }
-        guard let json = try JSONSerialization.jsonObject(with: data) as? [String: Any],
-              let choices = json["choices"] as? [[String: Any]],
-              let first = choices.first,
-              let message = first["message"] as? [String: Any],
-              let content = message["content"] as? String else {
-            throw PolishError.decodeFailed
-        }
-        let trimmed = PolishOutputCleaner.clean(content)
-        guard !trimmed.isEmpty else { throw PolishError.modelReturnedEmpty }
-        return FinalText(text: trimmed, mode: mode)
-    }
-
-    /// Coding Plan 文档给的是 base URL `https://ark.cn-beijing.volces.com/api/coding/v3`，
-    /// OpenAI SDK 会自动追加 `/chat/completions`。我们裸 URLRequest 得手动补。
-    /// 用户已经填好完整 URL（含 /chat/completions）时不重复追加。
-    static func chatCompletionsURL(from endpoint: URL) -> URL {
-        let s = endpoint.absoluteString
-        if s.hasSuffix("/chat/completions") {
-            return endpoint
-        }
-        let trimmed = s.hasSuffix("/") ? String(s.dropLast()) : s
-        return URL(string: trimmed + "/chat/completions") ?? endpoint
-    }
-}
-
-enum PolishOutputCleaner {
-    private static let leadingBoilerplatePatterns: [String] = [
-        #"(?s)^根据[你您]?(?:给的|提供的)?内容[，,\s]*(?:我)?(?:已经|已)?(?:整理|优化)(?:好|完成)?(?:如下)?[：:\s]*"#,
-        #"(?s)^以下(?:是|为)?(?:整理|优化|结构化整理)后?的?内容(?:如下)?[：:\s]*"#,
-        #"(?s)^(?:整理|优化|结构化整理)(?:后?的?内容)?(?:如下)?[：:\s]*"#,
-    ]
-
-    static func clean(_ content: String) -> String {
-        var output = content.trimmingCharacters(in: .whitespacesAndNewlines)
-        output = stripMarkdownFence(from: output)
-
-        var changed = true
-        while changed {
-            changed = false
-            for pattern in leadingBoilerplatePatterns {
-                if let range = output.range(of: pattern, options: .regularExpression),
-                   range.lowerBound == output.startIndex {
-                    output.removeSubrange(range)
-                    output = output.trimmingCharacters(in: .whitespacesAndNewlines)
-                    changed = true
-                }
-            }
-        }
-
-        return output
-    }
-
-    private static func stripMarkdownFence(from text: String) -> String {
-        guard text.hasPrefix("```"), text.hasSuffix("```") else { return text }
-        var lines = text.components(separatedBy: .newlines)
-        guard lines.count >= 2 else { return text }
-        lines.removeFirst()
-        lines.removeLast()
-        return lines.joined(separator: "\n").trimmingCharacters(in: .whitespacesAndNewlines)
-    }
-}
diff --git a/Sources/OpenLessPolish/OpenAICompatibleLLMProvider.swift b/Sources/OpenLessPolish/OpenAICompatibleLLMProvider.swift
index 0c690f90..da10df7d 100644
--- a/Sources/OpenLessPolish/OpenAICompatibleLLMProvider.swift
+++ b/Sources/OpenLessPolish/OpenAICompatibleLLMProvider.swift
@@ -144,6 +144,8 @@ public final class OpenAICompatibleLLMProvider: LLMProvider, @unchecked Sendable
         guard let content = message["content"] as? String else {
             throw LLMError.parseError("message.content is not a string")
         }
-        return content
+        // 即便 prompt 明令禁止"根据您给的内容，整理如下..."这类引导句，部分模型仍会顽固加；
+        // 客户端再扫一道，让插入到光标位置的永远是干净正文。
+        return PolishOutputCleaner.clean(content)
     }
 }
diff --git a/Sources/OpenLessPolish/PolishOutputCleaner.swift b/Sources/OpenLessPolish/PolishOutputCleaner.swift
new file mode 100644
index 00000000..bb386df7
--- /dev/null
+++ b/Sources/OpenLessPolish/PolishOutputCleaner.swift
@@ -0,0 +1,48 @@
+import Foundation
+
+/// 清理 LLM 返回内容里常见的"引导套话"和 markdown 代码栅栏。
+///
+/// 即使我们在 prompt 里明确禁止"根据您给的内容，整理如下"等开场白，仍有部分模型会顽固加上；
+/// 在客户端再扫一遍确保插入到光标位置的就是干净正文。
+///
+/// 这是公共类型——之前藏在 DoubaoPolishClient 内部，B-3 抽成独立文件后被
+/// `OpenAICompatibleLLMProvider` 复用，并保留 `PolishOutputCleanerTests` 直接测试入口。
+public enum PolishOutputCleaner {
+    /// 已知会被加在正文最前面的引导套话正则集合（顺序无关，循环匹配）。
+    private static let leadingBoilerplatePatterns: [String] = [
+        #"(?s)^根据[你您]?(?:给的|提供的)?内容[，,\s]*(?:我)?(?:已经|已)?(?:整理|优化)(?:好|完成)?(?:如下)?[：:\s]*"#,
+        #"(?s)^以下(?:是|为)?(?:整理|优化|结构化整理)后?的?内容(?:如下)?[：:\s]*"#,
+        #"(?s)^(?:整理|优化|结构化整理)(?:后?的?内容)?(?:如下)?[：:\s]*"#,
+    ]
+
+    public static func clean(_ content: String) -> String {
+        var output = content.trimmingCharacters(in: .whitespacesAndNewlines)
+        output = stripMarkdownFence(from: output)
+
+        // 多模型可能叠加多次套话；循环到不再变化为止。
+        var changed = true
+        while changed {
+            changed = false
+            for pattern in leadingBoilerplatePatterns {
+                if let range = output.range(of: pattern, options: .regularExpression),
+                   range.lowerBound == output.startIndex {
+                    output.removeSubrange(range)
+                    output = output.trimmingCharacters(in: .whitespacesAndNewlines)
+                    changed = true
+                }
+            }
+        }
+
+        return output
+    }
+
+    /// 去掉首尾的 ```...``` 围栏（含语言标记行如 ```text）。
+    private static func stripMarkdownFence(from text: String) -> String {
+        guard text.hasPrefix("```"), text.hasSuffix("```") else { return text }
+        var lines = text.components(separatedBy: .newlines)
+        guard lines.count >= 2 else { return text }
+        lines.removeFirst()
+        lines.removeLast()
+        return lines.joined(separator: "\n").trimmingCharacters(in: .whitespacesAndNewlines)
+    }
+}
diff --git a/Tests/OpenLessCoreTests/LLMProviderRegistryTests.swift b/Tests/OpenLessCoreTests/LLMProviderRegistryTests.swift
new file mode 100644
index 00000000..23dffab7
--- /dev/null
+++ b/Tests/OpenLessCoreTests/LLMProviderRegistryTests.swift
@@ -0,0 +1,86 @@
+import XCTest
+@testable import OpenLessCore
+
+/// LLMProviderRegistry 的静态健康检查：5 家供应商各 1 条，id 不重复，URL 合法。
+///
+/// 这些断言看起来很无聊，但 registry 直接被设置 UI 和 vault 兜底逻辑用，
+/// 漏一条都会变成"用户加不了 provider / baseURL 解不出来"的运行期 bug。
+final class LLMProviderRegistryTests: XCTestCase {
+
+    func test_presets_haveExpectedCount() {
+        // Arrange
+        let presets = LLMProviderRegistry.presets
+
+        // Act / Assert
+        XCTAssertEqual(presets.count, 5, "B-3 计划列出的预设是 ark / openai / aliyun-dashscope / deepseek / moonshot")
+    }
+
+    func test_presets_includeAllExpectedProviderIds() {
+        // Arrange
+        let expected: Set<String> = ["ark", "openai", "aliyun-dashscope", "deepseek", "moonshot"]
+
+        // Act
+        let actualIds = Set(LLMProviderRegistry.presets.map(\.providerId))
+
+        // Assert
+        XCTAssertEqual(actualIds, expected)
+    }
+
+    func test_presets_haveUniqueProviderIds() {
+        // Arrange
+        let ids = LLMProviderRegistry.presets.map(\.providerId)
+
+        // Act / Assert
+        XCTAssertEqual(Set(ids).count, ids.count, "providerId 必须唯一，否则 vault 会被互相覆盖")
+    }
+
+    func test_presets_haveValidBaseURLs() {
+        for preset in LLMProviderRegistry.presets {
+            // Arrange
+            let url = preset.defaultBaseURL
+
+            // Act / Assert：URL 必须是 https + 有 host
+            XCTAssertEqual(url.scheme, "https", "preset \(preset.providerId) 的 baseURL 必须是 https，避免网络层降级")
+            XCTAssertNotNil(url.host, "preset \(preset.providerId) 的 baseURL 必须有 host")
+        }
+    }
+
+    func test_arkPreset_hasEmptyDefaultModel() {
+        // Ark 的 defaultModel 故意留空——endpoint id 是用户在控制台拿到的 hash，
+        // 不能预设。如果哪天默认填了一个看起来像 model 的字符串，UI 会误导用户。
+        let ark = LLMProviderRegistry.preset(for: "ark")
+        XCTAssertNotNil(ark)
+        XCTAssertEqual(ark?.defaultModel, "")
+    }
+
+    func test_nonArkPresets_haveDefaultModel() {
+        // OpenAI / DeepSeek / Moonshot / DashScope 都给了一个开箱即用的 model。
+        for preset in LLMProviderRegistry.presets where preset.providerId != "ark" {
+            XCTAssertFalse(preset.defaultModel.isEmpty, "preset \(preset.providerId) 应当有 defaultModel")
+        }
+    }
+
+    func test_presets_haveNonEmptyHelpText() {
+        for preset in LLMProviderRegistry.presets {
+            XCTAssertFalse(preset.helpText.isEmpty, "preset \(preset.providerId) 的 helpText 不能为空")
+        }
+    }
+
+    func test_preset_lookup_returnsRegistered() {
+        for preset in LLMProviderRegistry.presets {
+            let resolved = LLMProviderRegistry.preset(for: preset.providerId)
+            XCTAssertEqual(resolved, preset)
+        }
+    }
+
+    func test_preset_lookup_unknownReturnsNil() {
+        XCTAssertNil(LLMProviderRegistry.preset(for: "no-such-provider-xyz"))
+    }
+
+    func test_customSentinels_areDistinctFromPresetIds() {
+        // 添加 sheet 用 customProviderId 区分"预设 vs 自定义"——它必须不在预设列表里，
+        // 否则会被点击事件混淆。
+        let presetIds = Set(LLMProviderRegistry.presets.map(\.providerId))
+        XCTAssertFalse(presetIds.contains(LLMProviderRegistry.customProviderId))
+    }
+}
diff --git a/Tests/OpenLessPersistenceTests/CredentialsVaultMultiProviderTests.swift b/Tests/OpenLessPersistenceTests/CredentialsVaultMultiProviderTests.swift
new file mode 100644
index 00000000..1f3f42c6
--- /dev/null
+++ b/Tests/OpenLessPersistenceTests/CredentialsVaultMultiProviderTests.swift
@@ -0,0 +1,253 @@
+import XCTest
+import OpenLessCore
+@testable import OpenLessPersistence
+
+/// CredentialsVault 多 LLM provider 扩展（B-3）的集成测试。
+///
+/// 用例策略与 CredentialsMigrationTests 一致：每个 case 独立 temp 目录，
+/// 通过 vault 的 public API 验证多 provider 行为。
+final class CredentialsVaultMultiProviderTests: XCTestCase {
+
+    // MARK: - 辅助
+
+    private func makeTempDirectory() -> URL {
+        let dir = FileManager.default.temporaryDirectory
+            .appendingPathComponent("openless-multi-provider-\(UUID().uuidString)", isDirectory: true)
+        try? FileManager.default.createDirectory(at: dir, withIntermediateDirectories: true)
+        addTeardownBlock {
+            try? FileManager.default.removeItem(at: dir)
+        }
+        return dir
+    }
+
+    /// 写一份 v0 字典文件（点号风格 key），让 vault 自动迁移。
+    private func writeV0File(_ dict: [String: String], to dir: URL) throws {
+        let url = dir.appendingPathComponent("credentials.json")
+        let data = try JSONSerialization.data(withJSONObject: dict, options: [.prettyPrinted])
+        try data.write(to: url)
+    }
+
+    // MARK: - active provider id
+
+    func test_freshInstall_activeLLMProviderId_defaultsToArk() {
+        // Arrange
+        let dir = makeTempDirectory()
+
+        // Act
+        let vault = CredentialsVault(directoryURL: dir)
+        let active = vault.activeLLMProviderId
+
+        // Assert：B-2 的默认 active.llm 是 "ark"，B-3 改成多 provider 后语义不变。
+        XCTAssertEqual(active, "ark")
+    }
+
+    func test_v0Migrated_activeLLMProviderId_isArk() throws {
+        // Arrange：典型迁移场景——从 v0 翻译过来 active.llm 应是 ark。
+        let dir = makeTempDirectory()
+        try writeV0File([
+            "ark.api_key": "sk-ark",
+            "ark.model_id": "deepseek-v3-2"
+        ], to: dir)
+
+        // Act
+        let vault = CredentialsVault(directoryURL: dir)
+
+        // Assert
+        XCTAssertEqual(vault.activeLLMProviderId, "ark")
+    }
+
+    func test_setActive_persists() throws {
+        // Arrange
+        let dir = makeTempDirectory()
+
+        // 先写一个 deepseek provider 进去（可以是空字段）。
+        let vault = CredentialsVault(directoryURL: dir)
+        vault.setLLMProviderConfig(OpenAICompatibleConfig(
+            providerId: "deepseek",
+            displayName: "DeepSeek",
+            baseURL: URL(string: "https://api.deepseek.com/v1")!,
+            apiKey: "sk-deepseek",
+            model: "deepseek-chat"
+        ))
+
+        // Act
+        vault.activeLLMProviderId = "deepseek"
+
+        // Assert：内存视图
+        XCTAssertEqual(vault.activeLLMProviderId, "deepseek")
+
+        // 再开一个新 vault 实例确认落盘。
+        let vault2 = CredentialsVault(directoryURL: dir)
+        XCTAssertEqual(vault2.activeLLMProviderId, "deepseek")
+    }
+
+    // MARK: - configuredLLMProviderIds
+
+    func test_configuredIds_emptyVault_returnsActive() {
+        // Arrange
+        let dir = makeTempDirectory()
+
+        // Act
+        let vault = CredentialsVault(directoryURL: dir)
+        let ids = vault.configuredLLMProviderIds
+
+        // Assert：vault 没有任何条目时，至少要返回 active id（picker 不能空）。
+        XCTAssertEqual(ids, ["ark"])
+    }
+
+    func test_configuredIds_returnsAllConfigured() throws {
+        // Arrange
+        let dir = makeTempDirectory()
+        let vault = CredentialsVault(directoryURL: dir)
+        vault.setLLMProviderConfig(OpenAICompatibleConfig(
+            providerId: "ark",
+            displayName: "豆包 (Ark)",
+            baseURL: URL(string: "https://ark.cn-beijing.volces.com/api/v3")!,
+            apiKey: "ark-key",
+            model: "ep-1"
+        ))
+        vault.setLLMProviderConfig(OpenAICompatibleConfig(
+            providerId: "openai",
+            displayName: "OpenAI",
+            baseURL: URL(string: "https://api.openai.com/v1")!,
+            apiKey: "sk-openai",
+            model: "gpt-4o-mini"
+        ))
+        vault.setLLMProviderConfig(OpenAICompatibleConfig(
+            providerId: "deepseek",
+            displayName: "DeepSeek",
+            baseURL: URL(string: "https://api.deepseek.com/v1")!,
+            apiKey: "sk-deepseek",
+            model: "deepseek-chat"
+        ))
+
+        // Act
+        let ids = vault.configuredLLMProviderIds
+
+        // Assert：3 家全在；顺序 sorted。
+        XCTAssertEqual(ids, ["ark", "deepseek", "openai"])
+    }
+
+    // MARK: - setLLMProviderConfig / llmProviderConfig 往返
+
+    func test_setAndGetConfig_roundTrips() {
+        // Arrange
+        let dir = makeTempDirectory()
+        let vault = CredentialsVault(directoryURL: dir)
+        let cfg = OpenAICompatibleConfig(
+            providerId: "deepseek",
+            displayName: "DeepSeek",
+            baseURL: URL(string: "https://api.deepseek.com/v1")!,
+            apiKey: "sk-deep-12345",
+            model: "deepseek-chat",
+            extraHeaders: ["X-Custom": "value"],
+            temperature: 0.5
+        )
+
+        // Act
+        vault.setLLMProviderConfig(cfg)
+        let back = vault.llmProviderConfig(for: "deepseek")
+
+        // Assert：所有字段都应一一回读。
+        XCTAssertEqual(back?.providerId, cfg.providerId)
+        XCTAssertEqual(back?.displayName, cfg.displayName)
+        XCTAssertEqual(back?.baseURL, cfg.baseURL)
+        XCTAssertEqual(back?.apiKey, cfg.apiKey)
+        XCTAssertEqual(back?.model, cfg.model)
+        XCTAssertEqual(back?.temperature, cfg.temperature)
+        XCTAssertEqual(back?.extraHeaders, cfg.extraHeaders)
+    }
+
+    func test_getConfig_unknownProvider_returnsNilWithoutPreset() {
+        // Arrange
+        let dir = makeTempDirectory()
+
+        // Act
+        let vault = CredentialsVault(directoryURL: dir)
+        let cfg = vault.llmProviderConfig(for: "unknown-no-preset-xyz")
+
+        // Assert：自定义 + 没有任何条目 + 没有预设 → 兜不出 baseURL，应返回 nil。
+        XCTAssertNil(cfg)
+    }
+
+    func test_getConfig_presetWithoutEntry_usesPresetDefaults() {
+        // Arrange
+        let dir = makeTempDirectory()
+
+        // Act
+        let vault = CredentialsVault(directoryURL: dir)
+        // openai 没有 entry，但有 preset；llmProviderConfig 应 fall back 到 preset 的 baseURL。
+        let cfg = vault.llmProviderConfig(for: "openai")
+
+        // Assert
+        XCTAssertNotNil(cfg)
+        XCTAssertEqual(cfg?.baseURL.absoluteString, "https://api.openai.com/v1")
+        XCTAssertEqual(cfg?.displayName, "OpenAI")
+        XCTAssertEqual(cfg?.model, "gpt-4o-mini")
+        XCTAssertEqual(cfg?.apiKey, "")
+    }
+
+    // MARK: - removeLLMProvider
+
+    func test_removeLLMProvider_blocksDeletingActive() throws {
+        // Arrange
+        let dir = makeTempDirectory()
+        let vault = CredentialsVault(directoryURL: dir)
+
+        // Act / Assert：默认 active 是 ark，不能删。
+        XCTAssertThrowsError(try vault.removeLLMProvider("ark")) { err in
+            guard case CredentialsError.cannotRemoveActiveProvider(let id) = err else {
+                XCTFail("应该抛 cannotRemoveActiveProvider，实际：\(err)")
+                return
+            }
+            XCTAssertEqual(id, "ark")
+        }
+    }
+
+    func test_removeLLMProvider_removesNonActive() throws {
+        // Arrange
+        let dir = makeTempDirectory()
+        let vault = CredentialsVault(directoryURL: dir)
+        vault.setLLMProviderConfig(OpenAICompatibleConfig(
+            providerId: "deepseek",
+            displayName: "DeepSeek",
+            baseURL: URL(string: "https://api.deepseek.com/v1")!,
+            apiKey: "sk",
+            model: "deepseek-chat"
+        ))
+
+        // Act
+        try vault.removeLLMProvider("deepseek")
+
+        // Assert
+        XCTAssertNil(vault.llmProviderConfig(for: "deepseek")?.apiKey == "sk" ? () : ()) // sanity
+        let ids = vault.configuredLLMProviderIds
+        XCTAssertFalse(ids.contains("deepseek"))
+    }
+
+    func test_removeLLMProvider_unknownIdIsNoop() {
+        // Arrange
+        let dir = makeTempDirectory()
+        let vault = CredentialsVault(directoryURL: dir)
+
+        // Act / Assert：删一个根本不在的 id 不应抛错。
+        XCTAssertNoThrow(try vault.removeLLMProvider("never-existed"))
+    }
+
+    // MARK: - 兼容老 API
+
+    func test_legacyArkAccount_routesToActive() throws {
+        // Arrange
+        let dir = makeTempDirectory()
+        let vault = CredentialsVault(directoryURL: dir)
+
+        // 通过老 API 写入。
+        try vault.set("legacy-key", for: CredentialAccount.arkApiKey)
+
+        // Act：新的 multi-provider API 应能读出来。
+        let cfg = vault.llmProviderConfig(for: "ark")
+
+        // Assert
+        XCTAssertEqual(cfg?.apiKey, "legacy-key")
+    }
+}