Lantean Code
Roslyn Workbench MCP A LANTEAN CODE PROJECT

LOCAL ROSLYN MCP SERVER / C# & .NET

Roslyn Workbench MCP — Real Roslyn.
In your agent’s hands.

Give your AI coding agent the same compiler-powered intelligence behind Visual Studio. Discover real C# fixes and refactorings, inspect the changes, and decide when they’re written.

Start using Roslyn Workbench View on GitHub

✓ Open source / MIT ·✓ Runs locally ·✓ Inspection-only by default

ROSLYN WORKBENCH / SYMBOL RENAME
LOCAL
C#OrderService.cs/ Services
✧
ROSLYN SEMANTIC REFACTORINGRename GetTotal → CalculateTotal
↗
● TRANSACTION PREVIEW2 files changed
✓ Changes staged for review NOT YET WRITTEN
ILLUSTRATIVE WORKFLOW · NOT A LIVE SCREENSHOT
230+ eligible Roslyn providers57 built-in tool definitionsLocal MCP over stdioExplicit transaction commits

01 / WHY ROSLYN WORKBENCH

Your agent can edit text.
Roslyn understands code.

Text-based edits can look right without understanding symbols, overloads or compiler diagnostics. Roslyn Workbench connects your agent to the .NET Compiler Platform so it can inspect the real structure of a C# solution and discover applicable Code Actions.

Explore Code Actions

02 / CAPABILITIES

From understanding
to safe changes.

Built for C# workflows where compiler semantics matter and source changes deserve review.

01 / CODE ACTIONS{ }

Real fixes. Real refactorings.

Discover context-appropriate compiler and analyzer fixes, supported refactorings, and Fix All operations through Roslyn's own providers.

ROSLYN CODE ACTIONS
02 / SEMANTIC NAVIGATION◎

See the whole codebase.

Locate symbol definitions, references, implementations, type hierarchies, callers and callees with compiler-aware precision.

SYMBOL INTELLIGENCE
03 / CODE ANALYSIS⌁

Understand before editing.

Inspect diagnostics, nullability, async behaviour, control flow, public APIs and potential change impact without loading entire solutions into context.

COMPILER-AWARE ANALYSIS
04 / TRANSACTIONS↺

Review the change. Then commit.

Stage source changes, inspect a diff, detect conflicts and roll back. Nothing writes source files until an explicit transaction commit.

REVIEWABLE SOURCE CHANGES

03 / THE WORKFLOW

Compiler-aware.
Human-reviewable.

Your agent can discover and prepare changes without immediately changing your source files.

01

Resolve

Resolve a symbol for renaming or discover applicable Code Actions.

02

Stage

Stage the selected operation inside a transaction.

03

Review

Inspect the resulting diff and decide what happens next.

04

Commit or roll back

Write the reviewed changes explicitly, or discard them.

04 / GET STARTED

Your next C# session,
a little smarter.

Runs locally with a supported .NET 10 SDK. Connect any MCP client that supports local stdio servers and start in inspection-only mode.

Read installation guide View on NuGet
.NET TOOL PIN A RELEASE

Run the latest published stable version:

dnx [email protected] --yes -- --version

Latest stable release: 1.2.0. The command pins that published version; for permanent installation and client configuration, see the getting started guide.

▸ Windows & Linux x64▸ .NET 10 SDK▸ MIT licence

OPEN SOURCE / BUILT BY LANTEAN CODE

Put Roslyn Workbench
to work.

Real C# semantics, reviewable changes, and your development workflow still in your control.

Explore the repository