docs: add documentation for RAGDocument (#1693)

# What does this PR do?


## Test Plan

docs/_static/llama-stack-spec.html

@@ -7787,7 +7787,8 @@
                 "type": "object",
                 "properties": {
                     "document_id": {
-                        "type": "string"
+                        "type": "string",
+                        "description": "The unique identifier for the document."
                     },
                     "content": {
                         "oneOf": [
@@ -7806,10 +7807,12 @@
                             {
                                 "$ref": "#/components/schemas/URL"
                             }
-                        ]
+                        ],
+                        "description": "The content of the document."
                     },
                     "mime_type": {
-                        "type": "string"
+                        "type": "string",
+                        "description": "The MIME type of the document."
                     },
                     "metadata": {
                         "type": "object",
@@ -7834,7 +7837,8 @@
                                     "type": "object"
                                 }
                             ]
-                        }
+                        },
+                        "description": "Additional metadata for the document."
                     }
                 },
                 "additionalProperties": false,
@@ -7843,7 +7847,8 @@
                     "content",
                     "metadata"
                 ],
-                "title": "RAGDocument"
+                "title": "RAGDocument",
+                "description": "A document to be used for document ingestion in the RAG Tool."
             },
             "InsertRequest": {
                 "type": "object",

docs/_static/llama-stack-spec.yaml

@@ -5375,6 +5375,7 @@ components:
       properties:
         document_id:
           type: string
+          description: The unique identifier for the document.
         content:
           oneOf:
             - type: string
@@ -5383,8 +5384,10 @@ components:
               items:
                 $ref: '#/components/schemas/InterleavedContentItem'
             - $ref: '#/components/schemas/URL'
+          description: The content of the document.
         mime_type:
           type: string
+          description: The MIME type of the document.
         metadata:
           type: object
           additionalProperties:
@@ -5395,12 +5398,15 @@ components:
               - type: string
               - type: array
               - type: object
+          description: Additional metadata for the document.
       additionalProperties: false
       required:
         - document_id
         - content
         - metadata
       title: RAGDocument
+      description: >-
+        A document to be used for document ingestion in the RAG Tool.
     InsertRequest:
       type: object
       properties:

llama_stack/apis/tools/rag_tool.py

@@ -17,6 +17,15 @@ from llama_stack.schema_utils import json_schema_type, register_schema, webmetho
 
 @json_schema_type
 class RAGDocument(BaseModel):
+    """
+    A document to be used for document ingestion in the RAG Tool.
+
+    :param document_id: The unique identifier for the document.
+    :param content: The content of the document.
+    :param mime_type: The MIME type of the document.
+    :param metadata: Additional metadata for the document.
+    """
+
     document_id: str
     content: InterleavedContent | URL
     mime_type: str | None = None