rvt-mcp

<!-- mcp-name: io.github.bimwright/rvt-mcp --> <p align="center"> <img src="https://raw.githubusercontent.com/bimwright/.github/master/assets/logos/rvt-mcp.png" alt="rvt-mcp" width="180" /> </p> <h1 align="center">rvt-mcp</h1> <p align="center"> MCP gateway for Autodesk Revit — local tools for agents, optional personal bake loop </p> <p align="center"> <a href="https://github.com/bimwright/rvt-mcp/actions/workflows/build.yml"><img src="https://github.com/bimwright/rvt-mcp/actions/workflows/build.yml/badge.svg" alt="build" /></a> <a href="LICENSE"><img src="https://img.shields.io/badge/license-Apache%202.0-blue.svg" alt="license" /></a> <a href="#supported-revit-versions"><img src="https://img.shields.io/badge/Revit-2022--2027-186BFF" alt="Revit 2022-2027" /></a> <a href="#tools"><img src="https://img.shields.io/badge/MCP-229%20tools-6C47FF" alt="MCP tools" /></a> </p> <p align="center"> English · <a href="README.vi.md">Tiếng Việt</a> · <a href="README.zh-CN.md">简体中文</a> · <a href="README.ja.md">日本語</a> </p>

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Install

Client machines should use the setup ZIP from GitHub Releases. It bundles a self-contained MCP server and Revit 2022–2027 plugins — no .NET SDK, NuGet global tool, or source clone.

AI agents: download RvtMcp.Setup-*-win-x64.zip from the latest release and run the installer. Do not clone, build, or dotnet tool install unless the user asked for a developer setup. Protocol: AGENTS.md.

$tag = (Invoke-RestMethod https://api.github.com/repos/bimwright/rvt-mcp/releases/latest).tag_name
$zip = "$env:TEMP\RvtMcp.Setup-$tag-win-x64.zip"
$dir = "$env:TEMP\RvtMcp.Setup-$tag-win-x64"
Invoke-WebRequest "https://github.com/bimwright/rvt-mcp/releases/download/$tag/RvtMcp.Setup-$tag-win-x64.zip" -OutFile $zip
Expand-Archive $zip -DestinationPath $dir -Force

powershell -ExecutionPolicy Bypass -File "$dir\install.ps1" -WhatIf
powershell -ExecutionPolicy Bypass -File "$dir\install.ps1"

The installer detects Revit 2022–2027, installs matching plugins, copies the server under %LOCALAPPDATA%\RvtMcp\rvt\server\<version>\, and wires detected MCP clients. Override with -Client codex|opencode|claude|kilo|none.

Do not install v0.5.0 or earlier ZIPs. Do not dotnet tool install -g Bimwright.Rvt.Server (legacy 0.1–0.3). Do not use NuGet instead of this ZIP on a Revit client machine — the tool package has no add-in.

For AutoCAD, use dwg-mcp separately — different product, different install.

Check that it works

1. Open Revit with a model.
2. Start the MCP connection from the ribbon (BIMwright / RvtMcp panel).
3. From the MCP client, list tools, then call revit_get_current_view_info.

You should get something like:

{ "viewName": "Level 1", "viewType": "FloorPlan", "levelName": "Level 1", "scale": 100 }

If that fails, install is not done yet — fix client config / plugin load before anything else.

Upgrade an existing installation

Updates are manual. Close all Revit windows and stop the MCP connection in your AI client, extract the new release ZIP into a separate folder, then run its install.ps1 -WhatIf followed by install.ps1. Upgrade the server and plugins together; restart Revit and the MCP client, then repeat the checks above. Do not uninstall first: the full uninstaller also removes personal ToolBaker data and logs.

The unreleased installer in this source tree preserves existing rvt-mcp arguments, environment, enabled/disabled state and other options while updating the executable path. It leaves other entries (including legacy aliases) intact. Custom launcher wrappers and unsupported TOML layouts require -Client none plus a manual path update; project-level configs are not scanned. These protections are not in the published v0.6.1 installer.

Before replacing files, the new installer checks package checksums when a manifest is present, validates every selected plugin ZIP, stages the payload and refuses installation while Revit is running. Caught installation errors restore earlier plugin/server/config changes. Config backups use <config>.rvtmcp.bak. If rollback is blocked by file locks or permissions, the error identifies retained .rvtmcp-rollback-* backups; hard termination or power loss requires manual recovery. See installer verification.

Uninstall

From the setup ZIP root (or this repo’s scripts/):

# Setup ZIP layout:
powershell -ExecutionPolicy Bypass -File .\uninstall.ps1 -WhatIf
powershell -ExecutionPolicy Bypass -File .\uninstall.ps1 -Yes

# Clone layout:
powershell -ExecutionPolicy Bypass -File .\scripts\uninstall-all.ps1 -WhatIf
powershell -ExecutionPolicy Bypass -File .\scripts\uninstall-all.ps1 -Yes

Removes plugins, self-contained server, client entries, discovery files, logs, and ToolBaker cache.

Developer install

git clone https://github.com/bimwright/rvt-mcp.git
cd rvt-mcp
dotnet build src/RvtMcp.sln -c Debug
powershell -ExecutionPolicy Bypass -File .\scripts\install.ps1 -SourceDir . -Client none

Close every Revit first — the build deploys plugin DLLs into %APPDATA%\Autodesk\Revit\Addins\<year>\RvtMcp\. install.ps1 finds Revit 2022–2027, copies the server under %LOCALAPPDATA%\RvtMcp\rvt\server\<version>\, and wires detected MCP clients (-Client codex|opencode|claude|kilo|none, -Years 2024 for one year).

Optional — NuGet server only (does not install Revit plugins). Use this if the add-in is already on the machine (ZIP or a local build) and you want the MCP server on PATH:

dotnet tool uninstall -g Bimwright.Rvt.Server   # skip if you never installed the 0.1–0.3 tool
dotnet tool install -g RvtMcp.Server --version 0.6.1

Command name: rvt-mcp. Keep using the GitHub Release ZIP for plugins. Bimwright.Rvt.Server is obsolete.

Migrating from Bimwright.Rvt.* (v0.3 and earlier)

v0.4+ renamed packages and folders to RvtMcp.* (repo name and brand stay bimwright).

1. Close every Revit.
2. pwsh scripts/uninstall-old.ps1 — drops old %APPDATA%\…\Bimwright\ plugins and old server root; keeps user bake/journal data and migrates it to %LOCALAPPDATA%\RvtMcp\ on first new launch.
3. Install the current GitHub Release ZIP (Client install above). Do not install v0.5.0 or earlier packages. Uninstall the old global tool if present: dotnet tool uninstall -g Bimwright.Rvt.Server.
4. Point MCP clients at entry name rvt-mcp (old per-year bimwright-rvt-r22… entries are removed by the installer).

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What this is

rvt-mcp is a local bridge between an MCP client (Claude, Cursor, Codex, OpenCode, …) and a running Revit session.

Two processes:

| Piece | Role | |--------|------| | RvtMcp.Server | .NET 8 MCP server on stdio. No Revit reference — builds anywhere. | | RvtMcp.Plugin | One thin add-in per Revit year (2022–2027). Runs inside Revit, executes on the UI thread. |

Agent → MCP → server → localhost TCP (≤2024) or Named Pipe (≥2025) → plugin → Revit API.

Everything stays on the machine. No cloud relay is required for the gateway itself.

There is no Node/TypeScript sidecar. Server, plugins, handlers, and ToolBaker are C# end to end. Shared command code lives in src/shared/; each year is a small shell project with #if where the API drifted. Details: ARCHITECTURE.md.

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Why it exists

People who live in Revit already know what they want automated. The friction was always shipping that idea as software: learn enough C#/Dynamo, fight the API, package an add-in, survive version upgrades — or pay someone else, or buy a fixed tool that only half-matches the office.

Agents change the first half of that loop (describe the task, try it live). They do not remove transactions, units, selection, worksharing, or “did this just trash the model?” That is what this gateway is for: a typed tool surface for common work, plus an escape hatch when you need ad-hoc C# inside Revit, plus an optional path to turn repeated local patterns into personal tools (ToolBaker).

It is not a universal add-in for every firm. Offices differ. The bet is: start from a shared runtime, grow your tools on top.

Scope posture (honest): we do not mint a new MCP tool for every edge case. Prefer typed tools when they exist; for everything else use revit_send_code_to_revit (C# only). Family project management is covered; full Family Editor authoring suites and Revit Viewer hosts are out of scope for now — see docs/roadmap.md.

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How a normal session looks

1. Revit open with a model; plugin connected (ribbon).
2. MCP client starts rvt-mcp / the installed server.
3. Agent uses tools: query view/selection, create grids/rooms, sheets, MEP, export, … Lengths in mm at the tool boundary.
4. Several writes in one undo step: revit_batch_execute.
5. Multiple Revits running: revit_list_available_targets then revit_switch_target with a four-digit year (2024, not R24).

When no typed tool fits:

revit_send_code_to_revit   # C# body, compiled and run inside the plugin

That tool is on by default (toolset meta). Strip it with --read-only or --disable-toolbaker if you do not want agents compiling code in the model.

The source checkout also supports a C# body with helper type declarations and an opt-in failure preprocessor; these additions are not in the published v0.6.1 plugin. See send-code source forms and failure handling. Upgrade the server and plugin together so tool descriptions match the loaded runtime.

For stairs, use the conversation and send-code workflow: tested scripts plus sample questions to resolve layout, dimensions, and railing intent before adapting the code. A dedicated create_stairs tool is deferred.

ToolBaker (optional)

Default surface includes revit_send_code_to_revit. revit_list_baked_tools / revit_run_baked_tool need --toolsets toolbaker (or --toolsets all).

Adaptive bake (suggest new tools from usage) is off unless you enable it. When on, repeated patterns can show up under revit_list_bake_suggestions; you accept or dismiss explicitly. Nothing ships itself into your ribbon without that step.

Useful flags (also JSON / env — see Configuration):

| Goal | What to turn on | |------|------------------| | Learn tools from repeated typed calls | --enable-adaptive-bake | | Also cluster send_code bodies for suggestions | plus --cache-send-code-bodies (redacted; still local) | | Short-lived disk journal of send_code bodies | persistSendCodeBodies + TTL (default privacy keeps this off) |

Bake compile runs inside Revit via Roslyn — end users do not need Visual Studio. Details and privacy notes: docs/bake.md.

Toast (optional)

Completion toast in Revit is on by default. Turn off with the ribbon Toast button, enableToast: false in config, or BIMWRIGHT_ENABLE_TOAST=0. Only finished calls are shown (no “in progress” toast). Capture success can show a thumbnail when the file sits under the path allowlist. Ribbon Status also prints toast + bake/privacy flags so you can see what is enabled without guessing.

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Architecture (short)

MCP client (stdio)
    → RvtMcp.Server (.NET 8)
        → TCP (Revit 2022–2024) or Named Pipe (2025–2027)
            → Plugin shell (per year)
                → ExternalEvent → Revit API / transactions / undo

Handlers return plain DTOs — never live Revit objects on the wire.

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Tools

Counts (without counting personal baked tools):

| Mode | Tools | Notes | |------|------:|-------| | Default | 40 | query + create + view + meta | | --toolsets all | 229 | Full catalog | | all + adaptive bake | 232 | Adds 3 sugg