Reframe AI function calling article around MEAI tool calling abstractions

[Copilot]

• Analyze existing article and related documentation
• Create new understanding-ai-tools.md article focused on MEAI and provider-agnostic tool calling
• Add redirect from old understanding-openai-functions.md URL to new article
• Update the TOC entry from "OpenAI function calling" to "AI tool calling"
• Rename file to ai-tools.md
• Update title frontmatter to "AI tool calling"
• Update H1 heading to # AI tool calling
• Remove standalone MEAI intro paragraph
• Rename "Call functions" TOC section and child items to use "tools" language
• Add redirect_document_id: true to redirect entry

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Address feedback from Jeremy in AI docs</issue_title>
<issue_description>- Should this article be less scoped to Open AI and more focused on MEAI and the ways we can manage functions across all providers, not specifically just OpenAI?

• Should we consider adoptiong the phrase "tools" moving forward and deprecate the functions language to avoid confusion? I'm confident anytime we discuss "functions" we're talking about tools that the agent or model uses.

Originally posted by @JeremyLikness in #51536 (comment)
</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Address feedback from Jeremy in AI docs #51584

---

🔒 GitHub Advanced Security automatically protects Copilot coding agent pull requests. You can protect all pull requests by enabling Advanced Security for your repositories. Learn more about Advanced Security.

---

Internal previews

📄 File	🔗 Preview link
docs/ai/conceptual/ai-tools.md	AI tool calling
docs/ai/toc.yml	docs/ai/toc

[Copilot]

Pull request overview

This PR replaces an OpenAI-specific “function calling” conceptual article with a provider-agnostic “tool calling” overview centered on Microsoft.Extensions.AI abstractions, and updates navigation and redirects to preserve the old URL.

Changes:

• Add a new conceptual article, understanding-ai-tools.md, explaining tool calling in MEAI (including key types, parallel calling, and token considerations).
• Remove the old OpenAI-scoped article and add a redirection from the old path to the new conceptual URL.
• Update the AI docs TOC to point to the new conceptual article and rename the TOC entry.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
docs/ai/toc.yml	Updates the Concepts TOC entry to “AI tool calling” and points it to the new conceptual article.
docs/ai/conceptual/understanding-openai-functions.md	Removes the prior OpenAI-specific conceptual content (replaced by a provider-agnostic article).
docs/ai/conceptual/understanding-ai-tools.md	Introduces a MEAI-centric, provider-agnostic conceptual overview of tool calling.
.openpublishing.redirection.ai.json	Adds a redirect from the removed conceptual file path to the new published URL.

---

You can also share your feedback on Copilot code review. Take the survey.