Add capability host creation instructions and update agent version

[tinaem]

Added instructions for creating an account-level capability host and updated the hosted agent version section to reflect changes in replica parameters.

[prmerger-automator]

@tinaem : Thanks for your contribution! The author(s) and reviewer(s) have been notified to review your proposed change.

[learn-build-service-prod]

Learn Build status updates of commit 7ea9050:

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[v-dirichards]

Hi @tinaem - This pull request was opened in the public repo. PMs should work in the private repo, per the Microsoft Docs contributor guide. We can keep this PR open for review and merge, but would you make future content updates in the private repo? Thank you!

---

@aahill - Can you review the proposed changes?

Important: When the changes are ready for publication, adding a #sign-off comment is the best way to signal that the PR is ready for the review team to merge.

#label:"aq-pr-triaged"
@MicrosoftDocs/public-repo-pr-review-team

[Copilot]

Pull request overview

This PR adds documentation for creating an account-level capability host and updates the parameter requirements for the az cognitiveservices agent start command. The changes clarify that min/max replicas are now optional parameters when starting an agent deployment.

• Adds new section documenting capability host creation with public hosting environment enabled
• Updates replica parameters from required to optional in the agent start command documentation

[Copilot]

This cURL example contains hardcoded subscription ID, resource group name, and account name that appear to be specific to a test environment ("arthfa-ncus"). These should be replaced with placeholders or generic example values to prevent confusion and potential security issues.

Consider using placeholders like:

• {subscription-id} or your-subscription-id
• {resource-group-name} or your-resource-group
• {account-name} or your-foundry-account

Suggested change

	--url 'https://management.azure.com/subscriptions/96aede12-2f73-41cb-b983-6d11a904839b/resourceGroups/arthfa-ncus/providers/Microsoft.CognitiveServices/accounts/arthfa-ncus/capabilityHosts/accountcaphost?api-version=2025-10-01-preview' \
	--url 'https://management.azure.com/subscriptions/{subscription-id}/resourceGroups/{resource-group-name}/providers/Microsoft.CognitiveServices/accounts/{account-name}/capabilityHosts/accountcaphost?api-version=2025-10-01-preview' \

[Copilot]

The heading uses sentence case ("Capability Host") instead of the expected lowercase style for multi-word terms. According to Microsoft Writing Style Guide, headings should be in sentence case. This should be "Create account-level capability host" (with "capability host" in lowercase).

Suggested change

	### Create account-level Capability Host
	### Create account-level capability host

[Copilot]

The cURL command lacks introductory text explaining what the command does or when to use it. Consider adding a brief introduction before the code block, such as "To create the account-level capability host with public hosting enabled, use the following Azure REST API call:" This follows the pattern used elsewhere in the document (see lines 237-240, 293).

Suggested change

	To create the account-level capability host with public hosting enabled, use the following Azure REST API call:

[Copilot]

Extra space detected between "you" and "must" - should be a single space instead of two spaces.

Suggested change

	Updating capability hosts is not supported. If you have existing capability host for your Foundry account, you must delete the existing one and recreate it with the property "enablePublicHostingEnvironment" set to true.
	Updating capability hosts is not supported. If you have existing capability host for your Foundry account, you must delete the existing one and recreate it with the property "enablePublicHostingEnvironment" set to true.

[Copilot]

Missing article "an" before "existing capability host". The sentence should read "If you have an existing capability host for your Foundry account..."

Suggested change

	Updating capability hosts is not supported. If you have existing capability host for your Foundry account, you must delete the existing one and recreate it with the property "enablePublicHostingEnvironment" set to true.
	Updating capability hosts is not supported. If you have an existing capability host for your Foundry account, you must delete the existing one and recreate it with the property "enablePublicHostingEnvironment" set to true.

[georgeollis]

Could you clarify what the enablePublicHostingEnvironment parameter is intended to do? The API docs don’t make its behaviour very clear