clarify input

Author: PatrickFarley

articles/ai-services/openai/how-to/gpt-with-vision.md

@@ -36,7 +36,7 @@ Send a POST request to `https://{RESOURCE_NAME}.openai.azure.com/openai/deployme
 - `api-key`: {API_KEY} 
 
 **Body**: 
-The following is a sample request body. The format is the same as the chat completions API for GPT-4, except that the message content can be an array containing strings and images (either a URL to an image, or a base-64-encoded image). Remember to set a `"max_tokens"` value, or the return output will be cut off.
+The following is a sample request body. The format is the same as the chat completions API for GPT-4, except that the message content can be an array containing strings and images (either a valid HTTP or HTTPS URL to an image, or a base-64-encoded image). Remember to set a `"max_tokens"` value, or the return output will be cut off.
 
 ```json
 {
@@ -168,7 +168,7 @@ Send a POST request to `https://{RESOURCE_NAME}.openai.azure.com/openai/deployme
 
 **Body**: 
 
-The format is similar to that of the chat completions API for GPT-4, but the message content can be an array containing strings and images (either a URL to an image, or a base-64-encoded image).
+The format is similar to that of the chat completions API for GPT-4, but the message content can be an array containing strings and images (either a valid HTTP or HTTPS URL to an image, or a base-64-encoded image).
 
 You must also include the `enhancements` and `dataSources` objects. `enhancements` represents the specific Vision enhancement features requested in the chat. It has a `grounding` and `ocr` property, which each have a boolean `enabled` property. Use these to request the OCR service and/or the object detection/grounding service. `dataSources` represents the Computer Vision resource data that's needed for Vision enhancement. It has a `type` property which should be `"AzureComputerVision"` and a `parameters` property. Set the `endpoint` and `key` to the endpoint URL and access key of your Computer Vision resource. Remember to set a `"max_tokens"` value, or the return output will be cut off.