[Platform] Support model size variants

Author: OskarStark

src/platform/doc/index.rst

@@ -67,6 +67,24 @@ supports a specific feature, like ``Capability::INPUT_AUDIO`` or ``Capability::O
 **Options** are additional parameters that can be passed to the model, like ``temperature`` or ``max_tokens``, and are
 usually defined by the specific models and their documentation.
 
+**Model Size Variants**
+
+For providers like Ollama, you can specify model size variants using a colon notation (e.g., ``qwen3:32b``, ``llama3:7b``).
+If the exact model name with size variant is not found in the catalog, the system will automatically fall back to the base
+model name (``qwen3``, ``llama3``) and use its capabilities while preserving the full model name for the provider.
+
+You can also combine size variants with query parameters::
+
+    use Symfony\AI\Platform\Bridge\Ollama\ModelCatalog;
+
+    $catalog = new ModelCatalog();
+
+    // Get model with size variant
+    $model = $catalog->getModel('qwen3:32b');
+
+    // Get model with size variant and query parameters
+    $model = $catalog->getModel('qwen3:32b?temperature=0.5&top_p=0.9');
+
 **Supported Models & Platforms**
 
 * **Language Models**

src/platform/src/ModelCatalog/AbstractModelCatalog.php

@@ -32,15 +32,16 @@ public function getModel(string $modelName): Model
             throw new InvalidArgumentException('Model name cannot be empty.');
         }
 
-        $parsed = self::parseModelName($modelName);
+        $parsed = $this->parseModelName($modelName);
         $actualModelName = $parsed['name'];
+        $catalogKey = $parsed['catalogKey'];
         $options = $parsed['options'];
 
-        if (!isset($this->models[$actualModelName])) {
+        if (!isset($this->models[$catalogKey])) {
             throw new ModelNotFoundException(\sprintf('Model "%s" not found.', $actualModelName));
         }
 
-        $modelConfig = $this->models[$actualModelName];
+        $modelConfig = $this->models[$catalogKey];
         $modelClass = $modelConfig['class'];
 
         if (!class_exists($modelClass)) {
@@ -65,12 +66,13 @@ public function getModels(): array
 
     /**
      * Extracts model name and options from a model name string that may contain query parameters.
+     * Also resolves size variants (e.g., "model:23b") to their base model for catalog lookup.
      *
      * @param string $modelName The model name, potentially with query parameters (e.g., "model-name?param=value&other=123")
      *
-     * @return array{name: string, options: array<string, mixed>} An array containing the model name and parsed options
+     * @return array{name: string, catalogKey: string, options: array<string, mixed>} An array containing the model name, catalog lookup key, and parsed options
      */
-    protected static function parseModelName(string $modelName): array
+    protected function parseModelName(string $modelName): array
     {
         $options = [];
         $actualModelName = $modelName;
@@ -87,8 +89,18 @@ protected static function parseModelName(string $modelName): array
             $options = self::convertNumericStrings($options);
         }
 
+        // Determine catalog key: try exact match first, then fall back to base model
+        $catalogKey = $actualModelName;
+        if (!isset($this->models[$actualModelName]) && str_contains($actualModelName, ':')) {
+            $baseModelName = explode(':', $actualModelName, 2)[0];
+            if (isset($this->models[$baseModelName])) {
+                $catalogKey = $baseModelName;
+            }
+        }
+
         return [
             'name' => $actualModelName,
+            'catalogKey' => $catalogKey,
             'options' => $options,
         ];
     }

src/platform/tests/Bridge/Ollama/ModelCatalogTest.php

@@ -30,6 +30,7 @@ public static function modelsProvider(): iterable
         yield 'llama3' => ['llama3', Ollama::class, [Capability::INPUT_MESSAGES, Capability::OUTPUT_TEXT, Capability::OUTPUT_STRUCTURED, Capability::TOOL_CALLING]];
         yield 'mistral' => ['mistral', Ollama::class, [Capability::INPUT_MESSAGES, Capability::OUTPUT_TEXT, Capability::OUTPUT_STRUCTURED, Capability::TOOL_CALLING]];
         yield 'qwen3' => ['qwen3', Ollama::class, [Capability::INPUT_MESSAGES, Capability::OUTPUT_TEXT, Capability::OUTPUT_STRUCTURED, Capability::TOOL_CALLING]];
+        yield 'qwen3:32b' => ['qwen3:32b', Ollama::class, [Capability::INPUT_MESSAGES, Capability::OUTPUT_TEXT, Capability::OUTPUT_STRUCTURED, Capability::TOOL_CALLING]];
         yield 'qwen' => ['qwen', Ollama::class, [Capability::INPUT_MESSAGES, Capability::OUTPUT_TEXT, Capability::OUTPUT_STRUCTURED, Capability::TOOL_CALLING]];
         yield 'qwen2' => ['qwen2', Ollama::class, [Capability::INPUT_MESSAGES, Capability::OUTPUT_TEXT, Capability::OUTPUT_STRUCTURED, Capability::TOOL_CALLING]];
         yield 'qwen2.5' => ['qwen2.5', Ollama::class, [Capability::INPUT_MESSAGES, Capability::OUTPUT_TEXT, Capability::OUTPUT_STRUCTURED, Capability::TOOL_CALLING]];
@@ -45,6 +46,7 @@ public static function modelsProvider(): iterable
         yield 'nomic-embed-text' => ['nomic-embed-text', Ollama::class, [Capability::INPUT_MESSAGES, Capability::OUTPUT_TEXT, Capability::OUTPUT_STRUCTURED, Capability::INPUT_MULTIPLE]];
         yield 'bge-m3' => ['bge-m3', Ollama::class, [Capability::INPUT_MESSAGES, Capability::OUTPUT_TEXT, Capability::OUTPUT_STRUCTURED, Capability::INPUT_MULTIPLE]];
         yield 'all-minilm' => ['all-minilm', Ollama::class, [Capability::INPUT_MESSAGES, Capability::OUTPUT_TEXT, Capability::OUTPUT_STRUCTURED, Capability::INPUT_MULTIPLE]];
+        yield 'all-minilm:33m' => ['all-minilm:33m', Ollama::class, [Capability::INPUT_MESSAGES, Capability::OUTPUT_TEXT, Capability::OUTPUT_STRUCTURED, Capability::INPUT_MULTIPLE]];
     }
 
     protected function createModelCatalog(): ModelCatalogInterface