API & MCP

Everything a person can do on Hearth, a program or AI agent can do with the same inputs and get the identical result.

HTTP API

• GET https://hearth.usefulweb.app/api/v1/tools – catalog
• GET https://hearth.usefulweb.app/api/v1/tools/{id} – inputs, output schema, examples
• POST https://hearth.usefulweb.app/api/v1/tools/{id}/calculate – run a tool
• GET https://hearth.usefulweb.app/api/v1/workflows · POST https://hearth.usefulweb.app/api/v1/workflows/{id}/run
• OpenAPI 3.1: /openapi.json · /openapi.yaml
• Errors: application/problem+json; 422 includes per-field errors.

Every result contains

inputs (normalised, defaults applied), summary, result (validated against the published schema), units, assumptions, sources, warnings, computedAt and links.

MCP (Model Context Protocol)

• Streamable HTTP endpoint: https://hearth.usefulweb.app/mcp – protocol revisions 2026-07-28 (stateless) and 2025-11-25 / 2025-06-18 / 2025-03-26 (initialize handshake).
• Tools: weekly_meal_planner, leftover_chef, food_storage_guide, household_chore_rotator, chore_roulette, household_maintenance_calendar, disaster_prep_builder, moving_box_planner, will_it_fit, room_layout_optimizer, jet_lag_planner, travel_connection_checker, currency_converter, travel_exchange_fee_calculator, tip_bill_split_calculator, movie_night_consensus_picker, runtime_marathon_planner
• Local stdio connector: node src/mcp-stdio.ts

{
  "mcpServers": {
    "usefulweb": { "type": "http", "url": "https://hearth.usefulweb.app/mcp" }
  }
}