Change Risk Assessor MCP Server

Autonomous Model Context Protocol server for code change risk assessment with ultra-low token budget (50-100 tokens).

Installation

Global Install

npm install -g mcp-change-risk-assessor

Using npx (No Install)

npx mcp-change-risk-assessor

Related MCP server: change-firewall

Purpose

Provides a single MCP tool (assess_change_risk) that evaluates code changes and returns structured risk metadata for consumption by AI agents in IDEs.

Key Features:

• ✅ No API keys required

• ✅ Works offline

• ✅ Ultra-low token budget (50-100 tokens)

• ✅ 8-word reasoning limit

• ✅ 10-word advice limit

• ✅ Classification-based (not prose-based)

Usage

MCP Client Configuration

Add to your MCP client configuration (e.g., Claude Desktop, Cursor, Cline):

Using npx (recommended):

{
  "mcpServers": {
    "change-risk-assessor": {
      "command": "npx",
      "args": ["-y", "mcp-change-risk-assessor"]
    }
  }
}

If installed globally:

{
  "mcpServers": {
    "change-risk-assessor": {
      "command": "mcp-change-risk-assessor"
    }
  }
}

Tool Interface

Tool Name: assess_change_risk

Input Schema:

{
  "diff": "string (optional)",
  "files_changed": ["array of strings (optional)"],
  "language": "string (optional)",
  "context_hint": "string (optional)"
}

Output Schema:

{
  "risk_level": "low | medium | high",
  "risk_types": ["data_loss", "auth", "perf", "breaking_change", "infra", "unknown"],
  "confidence": 0.0,
  "reasoning": "max 8 words, fragments only",
  "agent_advice": "max 10 words, imperative"
}

Reasoning Examples:

• "auth logic changed, rollback unclear"

• "schema mutation, irreversible"

• "refactor only, no behavior delta"

Advice Examples:

• "run full test suite before deploy"

• "verify rollback plan exists"

• "standard review, check build"

Architecture

This MCP server acts as a pure tool definition that relies entirely on the host IDE's built-in LLM (Claude Code, Cursor, etc.) to perform risk analysis.

Ultra-Low Token Budget

Token Target: 50-100 tokens per invocation
Reasoning Limit: 8 words maximum
Advice Limit: 10 words maximum

The server enforces strict word limits to minimize token usage while preserving classification accuracy.

Responsibility Split

The MCP Server:

• Defines the tool name and classification framework

• Enforces strict word limits (8 words reasoning, 10 words advice)

• Validates and normalizes output schema

• Truncates overlong responses

The Host IDE's LLM:

• Reads the tool description

• Classifies risk immediately (single-pass, no chain-of-thought)

• Returns fragmented reasoning (no full sentences)

• Provides imperative advice (no explanations)

No External Dependencies

✅ No API keys required
✅ No external LLM calls
✅ No network requests
✅ No configuration needed
✅ Works offline

Classification Approach

Classification over explanation:

• Immediate risk judgment (HIGH/MEDIUM/LOW)

• Fragmented reasoning only (≤8 words)

• Bounded vocabulary (no file descriptions, no diff repetition)

• Single-pass judgment (no step-by-step reasoning)

Risk Classification

High Risk

• Irreversible data changes

• Auth/security logic modifications

• Infrastructure changes

• Breaking external contracts

Medium Risk

• Behavior changes with unclear test coverage

• Configuration or dependency updates

• Performance-sensitive logic modifications

Low Risk

• Comments only

• Formatting changes

• Renames without behavior change

• Test-only changes

• Refactors with no semantic delta

How It Works

// 1. IDE detects code change and calls the MCP tool
{
  "diff": "- const user = getUser()\n+ const user = await getUser()",
  "files_changed": ["src/auth/login.js"],
  "context_hint": "pre-commit"
}

// 2. Host IDE's LLM reads the tool description and analyzes the change
// (The MCP server does NOT perform this analysis)

// 3. Host IDE's LLM generates assessment following the schema

// 4. MCP server validates and normalizes the output
{
  "risk_level": "medium",
  "risk_types": ["auth"],
  "confidence": 0.65,
  "reasoning": "auth logic changed, async pattern",
  "agent_advice": "verify test coverage, check integration impacts"
}

Design Philosophy

• Pure MCP tool definition

• No external LLM calls or API keys

• Analysis performed by host IDE's LLM

• Schema validation and normalization only

• No data persistence or state

• Deterministic output schema

• Machine-readable output only

• Autonomous operation in IDE context

• Works offline