feat: add function tools to openai responses

docs/_static/llama-stack-spec.yaml

@@ -4467,6 +4467,71 @@ components:
         - type
       title: OpenAIResponseInputMessageContentText
     OpenAIResponseInputTool:
+      oneOf:
+        - $ref: '#/components/schemas/OpenAIResponseInputToolWebSearch'
+        - $ref: '#/components/schemas/OpenAIResponseInputToolFileSearch'
+        - $ref: '#/components/schemas/OpenAIResponseInputToolFunction'
+      discriminator:
+        propertyName: type
+        mapping:
+          web_search: '#/components/schemas/OpenAIResponseInputToolWebSearch'
+          file_search: '#/components/schemas/OpenAIResponseInputToolFileSearch'
+          function: '#/components/schemas/OpenAIResponseInputToolFunction'
+    OpenAIResponseInputToolFileSearch:
+      type: object
+      properties:
+        type:
+          type: string
+          const: file_search
+          default: file_search
+        vector_store_id:
+          type: array
+          items:
+            type: string
+        ranking_options:
+          type: object
+          properties:
+            ranker:
+              type: string
+            score_threshold:
+              type: number
+              default: 0.0
+          additionalProperties: false
+          title: FileSearchRankingOptions
+      additionalProperties: false
+      required:
+        - type
+        - vector_store_id
+      title: OpenAIResponseInputToolFileSearch
+    OpenAIResponseInputToolFunction:
+      type: object
+      properties:
+        type:
+          type: string
+          const: function
+          default: function
+        name:
+          type: string
+        description:
+          type: string
+        parameters:
+          type: object
+          additionalProperties:
+            oneOf:
+              - type: 'null'
+              - type: boolean
+              - type: number
+              - type: string
+              - type: array
+              - type: object
+        strict:
+          type: boolean
+      additionalProperties: false
+      required:
+        - type
+        - name
+      title: OpenAIResponseInputToolFunction
+    OpenAIResponseInputToolWebSearch:
       type: object
       properties:
         type: