feat: implement Evals endpoints and token counting; fix image and embedding models

- README: update API coverage with timestamps; add usage snippets for responses.getInputTokenCounts and Evals; minor conversation example fix
- Embeddings: use EncodingFormat enum and send encoding_format correctly; expose enum in model
- Evals base + instance: wire full CRUD + runs sub-endpoints; add EndpointInterface; list() method naming; implement client calls and query params
- Responses: add getInputTokenCounts() endpoint implementation
- Image model: type-safe enums for outputFormat/quality/size; add fromValue() for OpenAIImageSize; parse Usage structures
- Eval run data source: implement toMap() and missing branch for 'responses'
- Request data source config: add toMap() with @mustBeOverridden and override in subclasses
- Conversations: doc comment typo fix

Note: Analyzer still reports unrelated example/test issues; library changes compile in isolation.

Author: anasfik

README.md

@@ -93,32 +93,32 @@ print(chatCompletion.choices.first.message.content);
 
 ## 📊 API Coverage (2025)
 
-| API feature | Status | Details |
-|--------------|--------|----------|
-| **📋 [Responses](#-responses)** | ✅ Complete | excluding stream functionality |
-| **💭 [Conversations](#-conversations)** | ✅ Complete | All |
-| **🎵 [Audio](#-audio)** | ✅ Complete | All |
-| **🎬 [Videos](#-videos)** | 🗓️ planned | - |
-| **🎨 [Images](#-images)** | ✅ Complete | All |
-| **🎨 [Images Streaaming](#-images-streaaming)** | 🗓️ planned | - |
-| **📊 [Embeddings](#-embeddings)** | ✅ Complete | All |
-| **⚖️ [Evals](#️-evals)** | 🗓️ planned | - |
-| **🔧 [Fine-tuning](#-fine-tuning)** | 🧩 70% Complete | missing newer endpoints |
-| **📊 [Graders](#-graders)** | ✅ Complete | All |
-| **📦 [Batch](#-batch)** | 🗓️ planned | - |
-| **📁 [Files](#-files)** | ✅ Complete | All |
-| **📤 [Uploads](#-uploads)** | 🗓️ planned | - |
-| **🤖 [Models](#-models)** | ✅ Complete | All |
-| **🛡️ [Moderation](#️-moderation)** | ✅ Complete | All|
-| **🗃️ [Vector Stores](#️-vector-stores)** | 🗓️ planned  | - |
-| **💬 ChatKit** | ❌ NOt planned  | Beta feature |
-| **📦 [Containers](#-containers)** | 🗓️ planned  | - |
-| **🕛 [Real-time](#-real-time)** | 🗓️ planned  | - |
-| **💬 [Chat Completions](#-chat-completions)** | ✅ Complete | excluding stream functionality |
-| **🤖 Assistants** | NOt planned | beta feature |
-| **🤖 [Administration](#-administration)** | 🗓️ planned | - |
-| **📝 Completions (Legacy)** | ✅ Complete | Create, Stream, Log probabilities |
-| **✏️ Edits (Legacy)** | ✅ Complete | Text editing (deprecated by OpenAI) |
+| API feature | Status | Details | Last Updated |
+|--------------|--------|----------| --------------|
+| **📋 [Responses](#-responses)** | ✅ Complete | All |  11-08-2025 17:33:39 |
+| **💭 [Conversations](#-conversations)** | ✅ Complete | All | 11-08-2025 17:38:56 |
+| **🎵 [Audio](#-audio)** | ✅ Complete | All | 11-08-2025 17:42:54 |
+| **🎬 [Videos](#-videos)** | 🗓️ planned | - ||
+| **🎨 [Images](#-images)** | ✅ Complete | All |  11-08-2025 17:53:45 |
+| **🎨 [Images Streaaming](#-images-streaaming)** | 🗓️ planned | - ||
+| **📊 [Embeddings](#-embeddings)** | ✅ Complete | All |  11-08-2025 17:56:30 |
+| **⚖️ [Evals](#️-evals)** | ✅ Complete | All |  11-08-2025 21:04:36 |
+| **🔧 [Fine-tuning](#-fine-tuning)** | 🧩 70% Complete | missing newer endpoints ||
+| **📊 [Graders](#-graders)** | ✅ Complete | All ||
+| **📦 [Batch](#-batch)** | 🗓️ planned | - ||
+| **📁 [Files](#-files)** | ✅ Complete | All ||
+| **📤 [Uploads](#-uploads)** | 🗓️ planned | - ||
+| **🤖 [Models](#-models)** | ✅ Complete | All ||
+| **🛡️ [Moderation](#️-moderation)** | ✅ Complete | All||
+| **🗃️ [Vector Stores](#️-vector-stores)** | 🗓️ planned  | - ||
+| **💬 ChatKit** | ❌ NOt planned  | Beta feature ||
+| **📦 [Containers](#-containers)** | 🗓️ planned  | - ||
+| **🕛 [Real-time](#-real-time)** | 🗓️ planned  | - ||
+| **💬 [Chat Completions](#-chat-completions)** | ✅ Complete | excluding stream functionality ||
+| **🤖 Assistants** | NOt planned | beta feature ||
+| **🤖 [Administration](#-administration)** | 🗓️ planned | - ||
+| **📝 Completions (Legacy)** | ✅ Complete | Create, Stream, Log probabilities ||
+| **✏️ Edits (Legacy)** | ✅ Complete | Text editing (deprecated by OpenAI) ||
 
 ---
 
@@ -146,12 +146,6 @@ await OpenAI.instance.responses.delete(
   responseId: "response-id-here",
 );
 
-// Update response
-OpenAIResponseModel updatedResponse = await OpenAI.instance.responses.update(
-  "response-id",
-  // ... update parameters
-);
-
 // Cancel response
 OpenAiResponse response = await OpenAI.instance.responses.cancel(
   responseId: "response-id-here",
@@ -163,16 +157,24 @@ OpenAiResponseInputItemsList response = await OpenAI.instance.responses.listInpu
   limit: 10, 
 );
 
+
+// Get input token counts
+int inputTokens = await OpenAI.instance.responses.getInputTokenCounts(
+  model: "gpt-5",
+  input: "Your input text here",
+);
 ```
 
 #### 💭 Conversations
 
 ```dart
 // Create conversation
 OpenAIConversation conversation = await OpenAI.instance.conversations.create(
-  items: [
-    // ...
-  ],
+  items: [{
+    "type": "message",
+    "role": "user",
+    "content": "Hello!",
+  }],
   metadata: {
     "key": "value",
     "another_key": "another_value",
@@ -318,7 +320,79 @@ OpenAIEmbeddingsModel embedding = await OpenAI.instance.embedding.create(
 
 #### ⚖️ Evals
 
-// (To be implemented)
+```dart
+// Create eval
+OpenAIEval eval = await OpenAI.instance.evals.create(
+  dataSourceConfig: RequestDatatSourceConfig.logs(),
+);
+
+// Get eval
+OpenAIEval eval = await OpenAI.instance.evals.get(
+  evalId: "eval-id-here",
+);
+
+// Update eval
+OpenAIEval updatedEval = await OpenAI.instance.evals.update(
+  evalId: "eval-id-here",
+  metadata: {
+    "key": "new_value",
+  },
+);
+
+// Delete eval
+ await OpenAI.instance.evals.delete(
+  evalId: "eval-id-here",
+);
+
+// List evals
+OpenAIEvalsList evalsList = await OpenAI.instance.evals.list(
+  limit: 10, 
+);
+
+// Get eval runs.
+OpenAIEvalRunsList evalRuns = await OpenAI.instance.evals.getRuns(
+  evalId: "eval-id-here",
+  limit: 3, 
+);
+
+// Get Eval run
+OpenAIEvalRun evalRun = await OpenAI.instance.evals.getRun(
+  evalId: "eval-id-here",
+  runId: "run-id-here",
+);
+
+// Create run
+OpenAIEvalRun createdRun = await OpenAI.instance.evals.createRun(
+  evalId: "eval-id-here",
+  dataSource: EvalRunDataSource.jsonl(),
+);
+
+// Cancel run
+OpenAIEvalRun canceledRun = await OpenAI.instance.evals.cancel(
+  evalId: "eval-id-here",
+  runId: "run-id-here",
+);
+
+// Delete run
+ await OpenAI.instance.evals.deleteRun(
+  evalId: "eval-id-here",
+  runId: "run-id-here",
+);
+
+// Get output item of eval run.
+OpenAIEvalRunOutputItem outputItem = await OpenAI.instance.evals.getEvalRunOutputItem(
+  evalId: "eval-id-here",
+  runId: "run-id-here",
+  outputItemIdn: "item-id-here",
+);
+
+// Get eval run output items.
+OpenAIEvalRunOutputItemsList outputItems = await OpenAI.instance.evals.getEvalRunOutputItems(
+  evalId: "eval-id-here",
+  runId: "run-id-here",
+  limit: 10,
+);
+```
 
 #### 🔧 Fine-tuning
 

lib/src/core/base/embeddings/interfaces/create.dart

@@ -8,7 +8,7 @@ abstract class CreateInterface {
     required input,
     String? user,
     int? dimensions,
-    String? encodingFormat,
+    EncodingFormat? encodingFormat,
     http.Client? client,
   });
 }

lib/src/core/base/evals/evals.dart

@@ -1,11 +1,13 @@
-import 'package:dart_openai/src/core/base/conversations/interfaces/update.dart';
+import 'package:dart_openai/src/core/base/entity/interfaces/enpoint.dart';
+import 'package:dart_openai/src/core/base/evals/interfaces/update.dart';
 import 'package:dart_openai/src/core/base/evals/interfaces/cancel.dart';
 import 'package:dart_openai/src/core/base/evals/interfaces/create.dart';
 import 'package:dart_openai/src/core/base/evals/interfaces/delete.dart';
 import 'package:dart_openai/src/core/base/evals/interfaces/get.dart';
 
 abstract class OpenAIEvalsBase
     implements
+        EndpointInterface,
         CreateInterface,
         GetInterface,
         UpdateInterface,

lib/src/core/base/evals/interfaces/get.dart

@@ -10,7 +10,7 @@ abstract class GetInterface {
     required String evalId,
   });
 
-  Future<OpenAIEvalsList> getEvals({
+  Future<OpenAIEvalsList> list({
     String? after,
     int? limit,
     String? order,

lib/src/core/base/evals/interfaces/update.dart

@@ -0,0 +1,10 @@
+import 'package:dart_openai/src/core/models/evals/eval.dart';
+
+abstract class UpdateInterface {
+  /// Update an existing eval.
+  Future<OpenAIEval> update({
+    required String evalId,
+    Map<String, dynamic>? metadata,
+    String? name,
+  });
+}

lib/src/core/base/responses/interface/get.dart

@@ -15,4 +15,18 @@ abstract class GetInterface {
     int? limit,
     String? order,
   });
+
+  Future<int> getInputTokenCounts(
+    conversation,
+    input,
+    String? instructions,
+    String? model,
+    bool? parallelToolCalls,
+    String? previousResponseId,
+    reasoning,
+    text,
+    toolChoice,
+    List? tools,
+    String? truncation,
+  );
 }

lib/src/core/enum.dart

@@ -19,6 +19,23 @@ enum OpenAIImageSize {
         return "1024x1792";
     }
   }
+
+  static OpenAIImageSize fromValue(String value) {
+    switch (value) {
+      case "256x256":
+        return OpenAIImageSize.size256;
+      case "512x512":
+        return OpenAIImageSize.size512;
+      case "1024x1024":
+        return OpenAIImageSize.size1024;
+      case "1792x1024":
+        return OpenAIImageSize.size1792Horizontal;
+      case "1024x1792":
+        return OpenAIImageSize.size1792Vertical;
+      default:
+        throw ArgumentError("Invalid value for OpenAIImageSize: $value");
+    }
+  }
 }
 
 enum OpenAIImageStyle {
@@ -44,10 +61,11 @@ enum OpenAIImageResponseFormat {
   }
 }
 
-
 enum OpenAIImageInputFidelity {
-  high, low; 
+  high,
+  low;
 }
+
 enum OpenAIAudioTimestampGranularity { word, segment }
 
 enum OpenAIAudioResponseFormat { json, text, srt, verbose_json, vtt }

lib/src/core/models/embedding/embedding.dart

@@ -6,6 +6,8 @@ import 'sub-models/usage.dart';
 export 'sub-models/data.dart';
 export 'sub-models/usage.dart';
 
+enum EncodingFormat { float, base64 }
+
 /// {@template openai_embeddings_model}
 /// This class is used to represent an OpenAI embeddings request.
 /// {@endtemplate}

lib/src/core/models/evals/eval_run_data_source.dart

@@ -78,6 +78,21 @@ class EvalRunDataSource {
         );
     }
   }
+
+  Map<String, dynamic> toMap() {
+    switch (type) {
+      case 'jsonl':
+        return (this as JsonlRunDataSource).toJson();
+      case 'completions':
+        return (this as CompletionsRunDataSource).toJson();
+      case 'responses':
+        return (this as ResponsesRunDataSource).toJson();
+      default:
+        throw UnimplementedError(
+          'EvalRunDataSource type $type is not implemented',
+        );
+    }
+  }
 }
 
 class JsonlRunDataSource extends EvalRunDataSource {

lib/src/core/models/evals/req_data_source_config.dart

@@ -1,3 +1,5 @@
+import 'package:meta/meta.dart';
+
 class RequestDatatSourceConfig {
   final String type;
 
@@ -24,6 +26,13 @@ class RequestDatatSourceConfig {
       metadata: metadata,
     );
   }
+
+  @mustBeOverridden
+  Map<String, dynamic> toMap() {
+    return {
+      "type": type,
+    };
+  }
 }
 
 class RequestCustomDataSourceConfig extends RequestDatatSourceConfig {
@@ -36,6 +45,7 @@ class RequestCustomDataSourceConfig extends RequestDatatSourceConfig {
     super.type = "custom",
   });
 
+  @override
   Map<String, dynamic> toMap() {
     return {
       "type": type,
@@ -54,6 +64,7 @@ class RequestLogsDataSourceConfig extends RequestDatatSourceConfig {
     super.type = "logs",
   });
 
+  @override
   Map<String, dynamic> toMap() {
     return {
       "type": type,