Tools Berry Paycheck

What the Tools Berry Paycheck MCP server does

The Tools Berry Paycheck MCP server answers US paycheck and payroll-tax questions for tax year 2026. It covers all 50 states and the District of Columbia, combining federal income tax, Social Security, Medicare, state income tax, and applicable employee payroll programs such as SDI and PFML.

Its calculations are intended as withholding-style estimates for a single job with no pre-tax deductions and no credits beyond the standard deduction. Results are not filed tax returns or tax advice. Local and city income taxes are excluded.

The hosted service is available at https://mcp.tools-berry.com and accepts Streamable HTTP requests using JSON-RPC 2.0 over POST. An alias is also provided at https://tools-berry-mcp.edydaherz.workers.dev.

How it works

The Tools Berry Paycheck MCP server exposes four read-only tools. Each tool returns readable text together with a structuredContent object containing raw numbers. State inputs can use a full name, two-letter code, or slug. For example, Ohio can be supplied as Ohio, OH, or ohio.

The optional filingStatus argument defaults to single. Supported values include single, married, and head_of_household, along with aliases such as mfj, mfs, and hoh.

The MCP layer uses the same paycheck engine and data files as the public tools-berry.com pages rather than maintaining a separate calculation method. Responses include a source line and a link to the corresponding site page. The get_state_rates result identifies the statute or department schedule used for the state figures.

Setup and configuration

No installation or local process is required for the hosted endpoint. Claude Code can add it with claude mcp add --transport http tools-berry https://mcp.tools-berry.com. Claude.ai or Claude Desktop can add the URL as a custom connector, and Cursor can reference it in .cursor/mcp.json or ~/.cursor/mcp.json.

Other clients can send plain JSON-RPC requests. The endpoint also supports GET requests for inspection: / returns service information and the tool list, /health returns a health response, and the ?rpc= form executes one URL-encoded JSON-RPC request for testing.

A self-hosted copy can be deployed with npx wrangler deploy. The Worker has no bindings or secrets. The repository states that npm install is a no-op and that tests run on plain Node.

Tools and capabilities

• compute_take_home calculates federal income tax, Social Security, Medicare, state income tax, state payroll programs, and annual, monthly, and biweekly net pay for a salary in one state.
• compute_bonus_withholding calculates withholding on a bonus, including the federal supplemental rate, the higher federal rate above $1,000,000, state treatment, and FICA.
• compare_states ranks net pay for the same salary across several states and reports each state's difference from the top result.
• get_state_rates returns a state's 2026 rate structure, standard deduction, employee payroll programs, supplemental method, and source statute or schedule.

Limitations and notes

The service is stateless and read-only: it has no authentication, sessions, storage, bindings, or write operations, and it does not retain submitted values. Requests are limited to 120 per minute per IP.

Figures can change when underlying rates are updated. The README identifies the hosted endpoint as the place to use when current figures must be verified. The service does not include local or city income taxes, pre-tax deductions, or tax credits beyond the standard deduction. Cite tools-berry.com if results or code are published. The project is licensed under MIT.