Overview

| Property | Value | |----------|-------| | Language | TypeScript / Node 20+ | | npm package | business-central-mcp | | BC versions | BC27, BC28 (wire-compatible) | | Auth | NavUserPassword (OAuth on roadmap) | | Tools | 12 | | Tests | 284 unit/protocol + 111 integration | | License | MIT |

Install

VSCode

Click the badge. VSCode opens, prompts to add the server, and writes to your user mcp.json.

You will still need to set BC_BASE_URL, BC_USERNAME, and BC_PASSWORD in the entry's env block. VSCode opens the file for you to edit.

Workspace: create .vscode/mcp.json:

{
  "servers": {
    "business-central": {
      "command": "npx",
      "args": ["-y", "business-central-mcp"],
      "env": {
        "BC_BASE_URL": "http://your-bc-server/BC",
        "BC_USERNAME": "your-user",
        "BC_PASSWORD": "your-password"
      }
    }
  }
}

Claude Code

claude mcp add business-central \
  -e BC_BASE_URL=http://your-bc-server/BC \
  -e BC_USERNAME=you \
  -e BC_PASSWORD=secret \
  -- npx -y business-central-mcp

Scope it to the current project with --scope project. See claude mcp --help for scoping options.

Claude Desktop

1. Download the latest .dxt from Releases.
2. Double-click. Claude Desktop opens Settings → Extensions and prompts for BC URL, username, and password.
3. Restart Claude Desktop.

Edit claude_desktop_config.json:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json
• Linux: ~/.config/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "business-central": {
      "command": "npx",
      "args": ["-y", "business-central-mcp"],
      "env": {
        "BC_BASE_URL": "http://your-bc-server/BC",
        "BC_USERNAME": "your-user",
        "BC_PASSWORD": "your-password"
      }
    }
  }
}

Restart Claude Desktop.

Configuration

| Variable | Required | Default | Description | |----------|----------|---------|-------------| | BC_BASE_URL | Yes | — | BC server base URL, e.g. http://your-bc-server/BC | | BC_USERNAME | Yes | — | NavUserPassword username | | BC_PASSWORD | Yes | — | NavUserPassword password | | BC_PROFILE | No | server default | Profile id, e.g. BUSINESS MANAGER. Affects which Role Center loads and which pages Tell Me indexes. | | BC_TENANT_ID | No | default | Multi-tenant deployments only. | | BC_CLIENT_VERSION | No | 27.0.0.0 | Version reported to BC during session open. | | PORT | No | 3000 | HTTP transport port (stdio transport ignores this). | | LOG_LEVEL | No | info | debug / info / warn / error. | | LOG_DIR | No | ./logs | Directory for log files. | | STATE_DIR | No | ./.state | Directory for session state. | | BC_INVOKE_TIMEOUT | No | 30000 | Per-invoke timeout in ms. Kills hung sessions. | | BC_RECONNECT_MAX_RETRIES | No | 4 | Reconnect attempts after session death. | | BC_RECONNECT_BASE_DELAY | No | 1000 | Base delay (ms) for exponential reconnect backoff. |

What can it do?

| Tool | What it does | |---|---| | bc_open_page | Open any page by ID -- lists, cards, documents, role centers. Returns the page as sections[] with header, lines, factboxes, and Role Center cuegroup tiles. | | bc_read_data | Refresh a single section: filter, paginate, slice, project tab/columns. Returns the same Section shape as bc_open_page. | | bc_write_data | Write field values; BC validates and echoes confirmed values. Section-aware (lines, factboxes, header). | | bc_execute_action | Run header / row / wizard actions, OR drill down on Role Center cue tiles via cue input. | | bc_respond_dialog | Handle confirmation prompts and request pages | | bc_navigate | Select rows, drill down into records, field lookups | | bc_search_pages | Tell Me search. Returns { name, objectType, runTarget, departmentPath, category, score } per result. | | bc_close_page | Close a page and free server resources | | bc_switch_company | Switch to a different company mid-session | | bc_list_companies | Discover available companies | | bc_run_report | Execute reports and fill request page parameters | | bc_wizard_navigate | Drive NavigatePage / wizard flows (back / next / finish / cancel) |

How it works

This server speaks BC's internal WebSocket protocol directly -- the same protocol the browser-based web client uses. It was reverse-engineered from decompiled BC server assemblies. No OData endpoints, no SOAP services, no Selenium.

One WebSocket connection per session. All operations serialized through a promise queue. BC27 and BC28 are wire-compatible.

LLM (Claude / Copilot / etc.)
   |
   v   MCP (stdio or HTTP)
business-central-mcp
   |
   v   WebSocket + JSON-RPC
BC Web Service Tier (BC27 / BC28)
   |
   v   internal calls
BC Server

bc_open_page returns the page as a flat list of sections:

{
  "pageContextId": "session:page:21:abc",
  "pageType": "Card",
  "caption": "Customer Card",
  "isModal": false,
  "sections": [
    { "sectionId": "header",                       "kind": "header",  "fields": [...], "actions": [...] },
    { "sectionId": "factbox:Customer Statistics",  "kind": "factbox", "fields": [...] }
  ]
}

Each section carries its own content shape:

• Card-style (header on Card pages, factbox, requestPage): fields[] and (for header) actions[]
• List-style (lines on Documents, header on List pages, repeater subpages): rows[] and totalRowCount
• Cue tiles (Role Center hosted CardParts): cues[] with each tile's name, value, groupCaption, synopsis, hasAction. Drill down with bc_execute_action { section, cue }.

bc_read_data returns a single Section for the requested sectionId (defaults to "header"). The section ID for a FactBox or subpage comes from the bc_open_page response.

• Automatic reconnect with exponential backoff after session death
• Handles BC's ~15s NTLM auth slot hold after crashes
• Auto-dismisses license popups on fresh databases
• Invoke timeout kills hung sessions and triggers recovery
• Auto-recovery from LogicalModalityViolationException mid-session: reconciles the modal stack and retries transparently; falls back to session reset when BC keeps a confirm dialog sticky

Key files

| File | Purpose | |------|---------| | src/stdio-server.ts | npm bin entry -- stdio MCP transport | | src/server.ts | HTTP MCP transport entry | | src/mcp/ | MCP tool registry, schemas, request handler | | src/operations/ | One handler per tool (bc_open_page, bc_read_data, etc.) | | src/services/ | Page, data, action, navigation, search business logic | | src/protocol/ | WebSocket transport, wire types, captures | | src/session/ | Session lifecycle, modal stack, reconnect | | manifest.json | Claude Desktop Extension manifest | | scripts/build-dxt.ts | Builds .dxt artifact for Claude Desktop | | .github/workflows/release.yml | Builds + attaches .dxt on v* tag pushes | | ROADMAP.md | Deferred work (OAuth, Cursor, init wizard) |

Development

git clone https://github.com/SShadowS/business-central-mcp
cd business-central-mcp
npm install
npm run start:stdio-direct   # Run from source
npm test                     # 284 unit + protocol tests
npm run test:integration     # 111 integration tests against real BC (requires running BC server)

Roadmap

OAuth, Cursor support, an interactive init wizard, and a few protocol gaps. See ROADMAP.md for the full list and priorities.

Author: Torben Leth ([email protected]) License: MIT (see LICENSE)