Preserve dynamic profiles across tool continuations

README.md

@@ -515,6 +515,28 @@ but never become part of the session's transcript.
 > Otherwise, it throws `SystemLanguageModel.Error.dynamicInstructionsUnavailable`
 > for a session with dynamic instructions.
 
+### Foundation Models 27 request options
+
+`ContextOptions` mirrors Foundation Models 27's schema-in-prompt and reasoning-level
+settings for compatibility-layer request construction. `GenerationOptions` also
+provides the OS 27 `samplingMode` spelling and `ToolCallingMode` values:
+
+```swift
+let context = ContextOptions(
+    includeSchemaInPrompt: true,
+    reasoningLevel: .moderate
+)
+let options = GenerationOptions(
+    samplingMode: .greedy,
+    toolCallingMode: .required
+)
+```
+
+The older `sampling` property and initializer remain source-compatible.
+Tool-calling mode is preserved in Codable transcripts and forwarded by the
+Foundation Models bridge on OS 27. Other model providers can read the same
+option from their request's `GenerationOptions`.
+
 ### Reasoning in the transcript
 
 Reasoning is transcript content, separate from the answer in `response.content`.
@@ -654,6 +676,11 @@ say which API they follow.
 - `DynamicInstructions`, its builder, and `LanguageModelSession.init(model:dynamicInstructions:history:)`:
   [dynamic instructions](#dynamic-instructions),
   which follow the Foundation Models 27 API.
+- `ContextOptions`, `GenerationOptions.samplingMode`, and
+  `GenerationOptions.ToolCallingMode`:
+  [request options](#foundation-models-27-request-options), which follow the
+  Foundation Models 27 API while remaining available on the package's existing
+  deployment targets.
 - `Transcript.Entry.reasoning` and `Transcript.Reasoning`:
   [reasoning in the transcript](#reasoning-in-the-transcript),
   which follows the Foundation Models 27 API.

Sources/AnyLanguageModel/ContextOptions.swift

@@ -0,0 +1,27 @@
+/// Options that configure a model's request context.
+///
+/// This mirrors the Foundation Models 27 request-context surface while keeping
+/// the package available on its existing deployment targets.
+public struct ContextOptions: Sendable, Equatable {
+    /// The amount of reasoning the model should perform for a request.
+    public enum ReasoningLevel: Sendable, Equatable {
+        case light
+        case moderate
+        case deep
+        case custom(String)
+    }
+
+    /// Whether a structured-generation schema should also appear in the prompt.
+    public var includeSchemaInPrompt: Bool?
+
+    /// The amount of reasoning the model should perform.
+    public var reasoningLevel: ReasoningLevel?
+
+    public init(
+        includeSchemaInPrompt: Bool? = nil,
+        reasoningLevel: ReasoningLevel? = nil
+    ) {
+        self.includeSchemaInPrompt = includeSchemaInPrompt
+        self.reasoningLevel = reasoningLevel
+    }
+}

Sources/AnyLanguageModel/DynamicInstructions.swift

@@ -337,7 +337,7 @@ extension Instructions: PrimitiveDynamicInstructions {
     }
 }
 
-private func resolveDynamicInstructions(
+func resolveDynamicInstructions(
     _ dynamicInstructions: any DynamicInstructions
 ) -> ResolvedDynamicInstructions {
     func resolve<Content>(_ content: Content) -> ResolvedDynamicInstructions