MemoryLens MCP

On-demand .NET memory profiling with concrete, AI-actionable code fix suggestions — wraps JetBrains dotMemory with a heuristic-based rule engine.

Quick Start

VS Code / Visual Studio (via dnx)

Add to your MCP settings (.vscode/mcp.json or VS settings):

{
  "servers": {
    "memorylens": {
      "type": "stdio",
      "command": "dnx",
      "args": ["MemoryLens.Mcp", "--yes"]
    }
  }
}

Claude Code Plugin

claude install gh:MarcelRoozekrans/memorylens-mcp

.NET Global Tool

dotnet tool install -g MemoryLens.Mcp

Prerequisites

.NET 10 SDK or later

Available MCP Tools

Tool	Description
`ensure_dotmemory`	Downloads and verifies the JetBrains dotMemory CLI tool is available
`list_processes`	Lists running .NET processes available for profiling
`snapshot`	Captures a single memory snapshot of a target process
`compare_snapshots`	Captures two snapshots with configurable delay and compares them
`analyze`	Runs the rule engine against a captured snapshot and returns findings
`get_rules`	Lists all available analysis rules with their metadata

Built-in Rules

ID	Severity	Category	Description
ML001	critical	leak	Event handler leak detected
ML002	critical	leak	Static collection growing unbounded
ML003	high	leak	Disposable object not disposed
ML004	high	fragmentation	Large Object Heap fragmentation
ML005	medium	retention	Object retained longer than expected
ML006	medium	allocation	Excessive allocations in hot path
ML007	medium	retention	Closure retaining unexpected references
ML008	low	allocation	Array/list resizing without capacity hint
ML009	low	pattern	Finalizer without Dispose pattern
ML010	low	pattern	String interning opportunity

Configuration

Create a .memorylens.json file in your project root to customize rule behavior:

{
  "rules": {
    "ML001": { "enabled": true, "severity": "critical" },
    "ML002": { "enabled": true, "severity": "critical" },
    "ML003": { "enabled": true, "severity": "high" },
    "ML004": { "enabled": true, "severity": "high" },
    "ML005": { "enabled": true, "severity": "medium" },
    "ML006": { "enabled": true, "severity": "medium" },
    "ML007": { "enabled": true, "severity": "medium" },
    "ML008": { "enabled": true, "severity": "low" },
    "ML009": { "enabled": true, "severity": "low" },
    "ML010": { "enabled": true, "severity": "low" }
  }
}

Usage Examples

Single Snapshot

Capture a memory snapshot of a running process to inspect current memory state:

> /memorylens
> Take a snapshot of my running API (PID 12345)

Claude will call ensure_dotmemory, then snapshot with the target PID, then analyze the result and present findings ordered by severity.

Before/After Comparison

Detect memory growth by comparing two snapshots taken with a delay:

> /memorylens
> Check if my app has a memory leak — compare before and after processing 1000 requests

Claude will call compare_snapshots with a configurable wait period, then analyze the diff to identify objects that grew between snapshots.

License

MIT

memorylens-mcp