Abstract API

You run an MCP server that exposes three validation tools powered by Abstract API: Email Validation, Phone Validation, and Email Reputation. This server integrates with MCP clients to provide fast, structured validation results for AI workflows and validation pipelines.

How to use

You connect your MCP client to the server and call the available tools to validate emails, phone numbers, and email reputations. Tools are automatically registered and exposed by the FastMCP framework, so you can discover capabilities through your MCP client’s tooling interface. Use the Email Validation tool to verify syntax, deliverability, MX records, and other signals. Use the Phone Validation tool to normalize formats, identify country and carrier, and detect phone types. Use the Email Reputation tool to assess deliverability, sender information, domain security signals, and breach history. The server communicates over stdio, making it straightforward to integrate into existing MCP client pipelines.

To start, ensure your environment variable ABSTRACT_API_KEY is configured with your Abstract API key. The server will interact with Abstract API services to perform the validations and return structured results suitable for AI-driven workflows.

How to install

Prerequisites: You need Python 3.11 or newer and uv (fast Python package installer). You also require an Abstract API key.

Option 1 Using uv (Recommended)

# 1) Clone the repository
git clone https://github.com/avivshafir/abstractapi-mcp-server
cd abstractapi-mcp-server

# 2) Create a virtual environment and activate it
uv venv
source .venv/bin/activate  # On Windows: .venv\Scripts\activate

# 3) Install the package
uv pip install .

# 4) Set up environment variables
cp .env.example .env
# Edit .env and add your Abstract API key

Option 2 Using traditional pip

# 1) Clone the repository
git clone https://github.com/avivshafir/abstractapi-mcp-server
cd abstractapi-mcp-server

# 2) Create a virtual environment
python -m venv .venv
source .venv/bin/activate  # On Windows: .venv\Scripts\activate

# 3) Install dependencies
pip install -r requirements.txt

# 4) Set up environment variables
cp .env.example .env
# Edit .env and add your Abstract API key

Your .env file should contain:

ABSTRACT_API_KEY=your_abstract_api_key_here

Run commands to start the server in stdio mode (so MCP clients can connect):

# With uv (if the virtual environment is activated)
python server.py

# Or run directly with uv
uv run server.py

Additional configuration and notes

Integration with MCP clients is straightforward. You register the MCP server under a name and provide the runtime command that starts the local process. The server uses stdio transport for communication with MCP clients.

Error handling is comprehensive. The server validates API keys, handles HTTP errors from Abstract API responses, validates inputs, and provides meaningful error messages for debugging.

Rate limits from Abstract API vary by plan. Free plans typically allow a limited number of requests per second, while paid plans offer higher limits. Each API call consumes one credit regardless of outcome.

Development and structure notes: the project includes a FastMCP-powered server, with tools automatically registered via decorators, type-safe definitions, and async support. You can extend tools by adding new functions decorated with @mcp.tool() and documenting their parameters and return shapes.

Security considerations

Protect your Abstract API key and keep it out of version control. Use a dedicated environment file and ensure your deployment mechanism configures environment variables securely.

Only expose the MCP endpoints you intend to publish and monitor usage to respect rate limits and avoid abuse.

Troubleshooting

If you encounter authentication errors, verify that ABSTRACT_API_KEY is correctly set in your environment. Check that the server is running and that the MCP client is configured to connect via stdio to the server process.

Available tools

verify_email

Validates email addresses and returns comprehensive information including format, deliverability, MX presence, and various risk indicators.

validate_phone

Validates international phone numbers, formats them, identifies country and carrier, and provides type and location information.

check_email_reputation

Analyzes email reputation with deliverability metrics, sender details, domain security signals, and breach history.