[Vertex AI] Add presencePenalty and frequencyPenalty (firebase#13899)

Author: andrewheard

FirebaseVertexAI/CHANGELOG.md

@@ -76,6 +76,8 @@
   provided alongside the `blockReason`. (#13891)
 - [added] Added an optional `publicationDate` property that *may* be provided in
   `Citation`. (#13893)
+- [added] Added `presencePenalty` and `frequencyPenalty` parameters to
+  `GenerationConfig`. (#13899)
 
 # 11.3.0
 - [added] Added `Decodable` conformance for `FunctionResponse`. (#13606)

FirebaseVertexAI/Sources/GenerationConfig.swift

@@ -58,6 +58,34 @@ public struct GenerationConfig {
   /// (unbounded).
   public let maxOutputTokens: Int?
 
+  /// Controls the likelihood of repeating the same words or phrases already generated in the text.
+  ///
+  /// Higher values increase the penalty of repetition, resulting in more diverse output. The
+  /// maximum value for `presencePenalty`  is up to, but not including, `2.0`; the minimum value is
+  /// `-2.0`.
+  ///
+  /// > Note: While both `presencePenalty` and ``frequencyPenalty`` discourage repetition,
+  /// > `presencePenalty` applies the same penalty regardless of how many times the word/phrase has
+  /// > already appeared, whereas `frequencyPenalty` increases the penalty for *each* repetition of
+  /// > a word/phrase.
+  ///
+  /// > Important: Supported by `gemini-1.5-pro-002` and` gemini-1.5-flash-002` only.
+  public let presencePenalty: Float?
+
+  /// Controls the likelihood of repeating words, with the penalty increasing for each repetition.
+  ///
+  /// Higher values increase the penalty of repetition, resulting in more diverse output. The
+  /// maximum value for `frequencyPenalty`  is up to, but not including, `2.0`; the minimum value is
+  /// `-2.0`.
+  ///
+  /// > Note: While both `frequencyPenalty` and ``presencePenalty`` discourage repetition,
+  /// > `frequencyPenalty` increases the penalty for *each* repetition of a word/phrase, whereas
+  /// > `presencePenalty` applies the same penalty regardless of how many times the word/phrase has
+  /// > already appeared.
+  ///
+  /// > Important: Supported by `gemini-1.5-pro-002` and` gemini-1.5-flash-002` only.
+  public let frequencyPenalty: Float?
+
   /// A set of up to 5 `String`s that will stop output generation. If
   /// specified, the API will stop at the first appearance of a stop sequence.
   /// The stop sequence will not be included as part of the response.
@@ -88,11 +116,14 @@ public struct GenerationConfig {
   /// - Parameter topK: See ``topK``
   /// - Parameter candidateCount: See ``candidateCount``
   /// - Parameter maxOutputTokens: See ``maxOutputTokens``
+  /// - Parameter presencePenalty: See ``presencePenalty``
+  /// - Parameter frequencyPenalty: See ``frequencyPenalty``
   /// - Parameter stopSequences: See ``stopSequences``
   /// - Parameter responseMIMEType: See ``responseMIMEType``
   /// - Parameter responseSchema: See ``responseSchema``
   public init(temperature: Float? = nil, topP: Float? = nil, topK: Int? = nil,
               candidateCount: Int? = nil, maxOutputTokens: Int? = nil,
+              presencePenalty: Float? = nil, frequencyPenalty: Float? = nil,
               stopSequences: [String]? = nil, responseMIMEType: String? = nil,
               responseSchema: Schema? = nil) {
     // Explicit init because otherwise if we re-arrange the above variables it changes the API
@@ -102,6 +133,8 @@ public struct GenerationConfig {
     self.topK = topK
     self.candidateCount = candidateCount
     self.maxOutputTokens = maxOutputTokens
+    self.presencePenalty = presencePenalty
+    self.frequencyPenalty = frequencyPenalty
     self.stopSequences = stopSequences
     self.responseMIMEType = responseMIMEType
     self.responseSchema = responseSchema

FirebaseVertexAI/Tests/Unit/GenerationConfigTests.swift

@@ -47,6 +47,8 @@ final class GenerationConfigTests: XCTestCase {
     let topK = 40
     let candidateCount = 2
     let maxOutputTokens = 256
+    let presencePenalty: Float = 0.5
+    let frequencyPenalty: Float = 0.75
     let stopSequences = ["END", "DONE"]
     let responseMIMEType = "application/json"
     let generationConfig = GenerationConfig(
@@ -55,6 +57,8 @@ final class GenerationConfigTests: XCTestCase {
       topK: topK,
       candidateCount: candidateCount,
       maxOutputTokens: maxOutputTokens,
+      presencePenalty: presencePenalty,
+      frequencyPenalty: frequencyPenalty,
       stopSequences: stopSequences,
       responseMIMEType: responseMIMEType,
       responseSchema: .array(items: .string())
@@ -66,7 +70,9 @@ final class GenerationConfigTests: XCTestCase {
     XCTAssertEqual(json, """
     {
       "candidateCount" : \(candidateCount),
+      "frequencyPenalty" : \(frequencyPenalty),
       "maxOutputTokens" : \(maxOutputTokens),
+      "presencePenalty" : \(presencePenalty),
       "responseMIMEType" : "\(responseMIMEType)",
       "responseSchema" : {
         "items" : {