MCP Server for Business Central - Advanced Topics (Part 3)

Overview

This is part 3 of a series on the MCP server for Business Central, published 2026-01-21. It explains how the server exposes built-in APIs and lets you add custom APIs, and how the default configuration differs from named configurations that pre-load an explicit tool list.

It also covers the dynamic tools system, how API pages are named and described for language models, and the limits on tool counts in MCP hosts. It closes with agent instructions, model selection, and the sample proxy for hosts other than Copilot Studio. The proxy is sample code that is delivered as is, and an update is expected to remove the need for it.

Key points

• The MCP server is in public preview. It exposes all built-in APIs for data, and custom APIs can be added. API queries might be opened up in the future.
• The default configuration offers three dynamic tools: search, describe and invoke. The client passes keywords, a semantic search returns the top relevant tools, and the model then describes and invokes API pages over OData.
• Named configurations pre-load an explicit tool list for a specific business process, so no tool search is needed. Too many tools fill the model context and hit host limits.
• Copilot Studio supported around 70 tools when the video was recorded. The limit will likely change.
• API page tool names append the object type and ID to stay unique. Descriptions and the about text property help the model reason about what each API does.
• The discover additional objects setting exposes more readonly API pages. It can raise the chance of model errors, use more context and reduce performance.
• For hosts other than Copilot Studio, the bcmcp proxy sample is on BCTech samples (aka.ms/bct). It is only a sample delivered as is and is not part of the product. An update is expected to make setup easier and remove the need for the proxy.

Features

AL objects mentioned

As heard in the captions. A name that matches one object page by exact type and name links to it; the others stay as named.

• api “Job Q Log Entries” at 5:22
• other “bcmcp proxy” at 14:33

Quotes

• 1:15 “currently the MCP server exposes all the built-in APIs for data. You can also add your custom APIs.”
• 1:42 “We might open up for API queries in the future. So stay in tuned for that.”
• 3:17 “there is a limit to how many tools you can have which is why we have introduced the um dynamic tools system.”
• 7:01 “This will allow any agent to reason better over what your APIs are able to do.”
• 9:45 “right now when we record this video, Microsoft Copilot Studio is around 70 tools. That of course uh will likely change in the future.”
• 14:57 “we expect to release an update in the near future which will make the setup much easier and remove the need for the MCP”
• 15:39 “Make all functionality available in business central functional available to AI and agents and of course do it in a secure reliable way.”

Disclaimers in the video

• 0:45 preview: It’s currently in public preview.
• 1:42 coming-later: We might open up for API queries in the future.
• 14:57 subject-to-change: we expect to release an update in the near future which will make the setup much easier and remove the need for the MCP proxy
• 15:16 other: It’s not a part of the product. It’s a sample. It’s delivered as is.

Presenters (as heard): Kenny Pontopidan, Yen Smaller Peterson.