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

Merovingian MCP Server