LienDeadline

What LienDeadline MCP server does

LienDeadline MCP server helps AI assistants research mechanics lien and preliminary notice requirements for US construction material suppliers. It accepts job facts such as the state, project type, hiring relationship, delivery dates, and answers about events including final payment or termination. The calculation tools return applicable deadlines with the statute supporting each date.

The server also exposes reference material. State guides contain rule summaries, statute citations, deadline tables, and frequently asked questions. A directory tool lists guides for all 50 states and the District of Columbia.

When the available facts are insufficient, the project is public, or a jurisdiction is not covered by the relevant calculation rules, the result is marked review_required with a reason. The server does not send notices, file liens, or make payments.

How it works

An MCP client sends the state, dates, and other collected facts to the server. For the v3 workflow, get_supplier_questions first reports whether the requested state, project type, and hiring relationship are covered, then returns the questions, sources, and rule versions needed for calculation. calculate_supplier_deadlines_v3 uses those gathered facts to produce the result.

The simpler calculate_supplier_deadlines tool calculates preliminary notice and lien filing deadlines from delivery dates and yes, no, or unknown answers. Before returning a supplier deadline, the service checks that the result matches the facts submitted. A mismatch is reported as an error rather than presented as a date.

Setup and configuration

The hosted endpoint is available at https://mcp.liendeadline.com/mcp. It uses Streamable HTTP and requires no installation, account, authentication, or API key. Claude, Cursor, VS Code, Claude Code, Codex CLI, ChatGPT custom MCP servers, and other MCP clients can connect through their respective MCP configuration flows.

For local stdio use, install or run the npm package with npx -y liendeadline-mcp. Local execution requires Node.js 22.22 or newer. The local package exposes the complete tool set, including the customer API tools. Claude Desktop can also use the .mcpb package from a release.

The invoice-based local tools require a customer API key. The hosted endpoint's standard supplier calculations and guide tools do not require an API key.

Tools and capabilities

• calculate_supplier_deadlines: Calculates preliminary notice and lien filing deadlines from delivery dates and event answers.
• get_supplier_questions: Checks v3 coverage and returns required questions, sources, and rule versions.
• calculate_supplier_deadlines_v3: Calculates deadlines from the v3 fact set.
• get_state_lien_guide: Retrieves one state's rules, citations, deadline table, and FAQs.
• list_state_lien_guides: Lists guides for every state and DC with codes, titles, and slugs.
• calculate_lien_deadline: Calculates invoice-based deadlines; available only on the local server.
• list_supported_states: Lists jurisdictions accepted by the invoice calculation; available only on the local server.

LienDeadline MCP server currently documents calculated supplier deadlines for Florida and Kansas private projects. Additional states become available through the v3 tools as reviewed rules are released. The lien guides cover all 50 states and DC, while invoice-based calculations accept 51 jurisdictions when the required customer API access is available.

Limitations and notes

Coverage depends on the calculation workflow and the facts supplied. Unknown facts, unsupported states, and public projects can produce review_required rather than a date. The repository describes the service as a deadline research and calculation tool; users should review cited statutes and any result marked for review before acting.

Usage of calculations consumes plan usage. The server does not perform filing or notification actions, and no account or API key is needed for the hosted standard tools.