Hello Randula Ariyawanse,
Welcome to the Microsoft Q&A and thank you for posting your questions here.
I understand that you would like to know where you can find AI Search markdown parser in the portal as mentioned in the reference documentation.
The Azure AI Search markdown parser is accessible via the Import and vectorize data wizard in the Azure portal. Immediately after you initiated the Import and Vectorize Data Wizard On your search service's Overview page, click on Import and vectorize data.
During the Configure Data Source when you choose your data source containing the markdown files you wish to parse. Then, follow the prompts to connect and configure the data source appropriately.
You will be able to set Parsing Mode to Markdown within the wizard, when configuring the indexing settings, locate the "Parsing Mode" option. Then, Select "Markdown" from the available parsing modes.
NOTE:
It's currently available in specific Azure regions as you listed. If your Azure AI Search service is not located in one of these regions, the Import and vectorize data wizard may not be visible or accessible. To utilize this feature, consider deploying a new Azure AI Search service in one of the supported regions. If you are unable to find the markdown parser, it might be due to the feature being in public preview and not yet fully rolled out in all regions or subscriptions.
For more detailed guidance, on Import data wizards in the Azure portal. - https://learn.microsoft.com/en-us/azure/search/search-import-data-portal Markdown Tutorial. - https://learn.microsoft.com/en-us/azure/search/search-markdown-data-tutorial and https://learn.microsoft.com/en-us/azure/search/search-how-to-index-markdown-blobs
I hope this is helpful! Do not hesitate to let me know if you have any other questions.
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