Merovingian

Cross-repository dependency intelligence for AI agents via MCP.

Merovingian maps cross-repo dependencies — API contracts, shared schemas, consumer relationships — and detects breaking changes before they propagate. It answers: "What else will break if I change this?"

Part of the EvoIntel MCP Suite (Sentinel, Niobe, Merovingian, Seraph, Anno).

Features

• OpenAPI spec parsing — detects endpoints, request/response schemas, $ref resolution (recursive, with cycle detection), allOf/anyOf/oneOf support
• Pydantic model extraction — AST-parses Python files for BaseModel subclasses, no runtime imports needed
• Direction-aware breaking change detection — request vs response changes have opposite breaking semantics
• Consumer registry — track which services consume which endpoints
• Dependency graph — visualize producer/consumer relationships across repos
• Contract versioning — deterministic SHA256 spec hashing, version history with diff tracking
• MCP interface — 8 tools for AI agent consumption
• CLI — 12 commands via Typer with Rich output

Installation

pip install merovingian

Quick Start

# Register repositories
merovingian register user-service /path/to/user-service --type openapi
merovingian register billing-service /path/to/billing-service

# Scan for contracts
merovingian scan user-service

# Register consumer relationships
merovingian add-consumer billing-service user-service GET /users/{id}

# Check for breaking changes
merovingian breaking user-service

# Full impact assessment with consumer mapping
merovingian impact user-service

# View dependency graph
merovingian graph

# Contract version history
merovingian contracts user-service

CLI Commands

Command	Description
register <name> <path>	Register a repository for scanning
unregister <name>	Remove a registered repository
repos	List all registered repositories
scan <repo>	Scan and update endpoints
consumers	List consumer relationships
add-consumer <consumer> <producer> <method> <path>	Register a consumer
breaking <repo>	Check for breaking changes
impact <repo>	Full impact assessment with consumer mapping
contracts <repo>	View contract version history
graph	View dependency graph
feedback <target_id> <outcome>	Submit feedback
audit	View audit log

MCP Server

Add to your Claude Code configuration (~/.claude.json):

{
  "mcpServers": {
    "merovingian": {
      "command": "merovingian-mcp",
      "args": []
    }
  }
}

MCP Tools

Tool	Description
merovingian_register	Register a repository for contract scanning
merovingian_consumers	List consumers of endpoints
merovingian_breaking	Check for breaking changes
merovingian_impact	Full impact assessment with consumer mapping
merovingian_contracts	List contract versions
merovingian_graph	Query the dependency graph
merovingian_feedback	Submit feedback on assessments
merovingian_audit	Query the audit log

Breaking Change Detection

Merovingian classifies changes with direction-aware logic:

Breaking (blocks consumers):

• Endpoint removed
• Required field added to request body
• Response field removed
• Field type changed (non-widening)
• Optional field made required in request

Warning:

• Type widened (e.g., integer → number)
• Required field made optional in response

Info (non-breaking):

• Endpoint added
• Optional field added to request
• Response field added
• Summary/description changed

Configuration

Merovingian uses layered configuration: TOML file → environment variables → defaults.

Create .merovingian/config.toml in your project root:

[store]
db_name = "merovingian.db"

[scanner]
openapi_patterns = ["openapi.yaml", "openapi.json", "swagger.yaml", "swagger.json"]
pydantic_scan_dirs = ["src", "app", "lib"]

[mcp]
default_query_limit = 50

Part of the EvoIntel MCP Suite

Merovingian solves AI Blindness #3: Cross-Service Dependencies — API contracts, consumer relationships, and breaking changes that span repository boundaries.

Part of the EvoIntel MCP Suite by Evolving Intelligence AI: five tools for five blindnesses no model improvement will ever fix.

Tool	Blindness	Install
Sentinel	Project History	pip install git-sentinel
Niobe	Runtime Behavior	pip install niobe
Merovingian	Cross-Service Dependencies	pip install merovingian
Seraph	Code Quality	pip install seraph-ai
Anno	Web Content	npm install -g @evointel/anno

License

MIT