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DatumSpot

DatumSpot API

Every DatumSpot calculator, over HTTP — the same source-cited engine as the site. Free, no key, and stateless: an API call sends your calculator inputs to the edge, returns the result, and keeps no account or history. (The on-site tools, by contrast, run entirely in your browser.) Built for scripts, spreadsheets, and AI agents: a REST endpoint, an OpenAPI 3.1 spec for GPT Actions, and a remote MCP endpoint.

Try a live request → OpenAPI spec Explore /api

Free & keyless

No account, no API key, no rate-limit signup. Just call it.

Source-cited

Every regulated number cites its section — ADA, IRC, IBC, ASCE.

Stateless

No accounts and no stored history — each request is computed at the edge (your inputs are sent in the call).

AI-native

An OpenAPI 3.1 doc for GPT Actions and a JSON-RPC endpoint for MCP.

Quick start

Pass arguments as query params on a GET, or as a JSON body on a POST. Dimensions accept the same messy input the site does — 12' 6", 3810 mm, 4.5'.

Run a calculator (GET)

curl 'https://datumspot.com/api/calc/roof_pitch?value=6&unit=pitch'

Response:

{
  "tool": "roof_pitch",
  "ok": true,
  "summary": "6:12 = 26.6° = 50%.",
  "data": {
    "risePer12": 6,
    "angleDeg": 26.57,
    "percent": 50,
    "pitchLabel": "6:12",
    "angleLabel": "26.6°",
    "percentLabel": "50%"
  }
}

Run a calculator (POST JSON)

curl -X POST https://datumspot.com/api/calc/square_footage \
  -H 'content-type: application/json' \
  -d '{"lengthRaw":"12 ft","widthRaw":"10 ft","price":3.5}'

List every tool + schema

curl https://datumspot.com/api/tools

Endpoints

Method Path Purpose
GET /api Self-documenting index.
GET /api/tools Every calculator with its JSON-Schema input contract.
GET · POST /api/calc/{tool} Run a calculator — query params or a JSON body.
POST /api/mcp Remote MCP (JSON-RPC 2.0 over HTTP).
GET /api/openapi OpenAPI 3.1 doc — drop-in for a Custom GPT Action.
GET /api/health Liveness probe.

Use it with AI

Custom GPT Action

Point a GPT Action at the OpenAPI doc — each calculator becomes an operation with a typed schema.

https://datumspot.com/api/openapi

MCP — remote (HTTP)

A stateless JSON-RPC 2.0 endpoint. Send initialize, tools/list, tools/call, or ping.

POST https://datumspot.com/api/mcp

MCP — local (stdio)

Prefer a local server? The @datumspot/calc package ships a stdio MCP binary. Add it to Claude Desktop: 

{
  "mcpServers": {
    "datumspot": { "command": "npx", "args": ["-y", "@datumspot/calc"] }
  }
}

List the tools over remote MCP:

curl -X POST https://datumspot.com/api/mcp \
  -H 'content-type: application/json' \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'

Tools (18)

Full schemas →

Reference estimates. Results are for preliminary use — verify every code number against the adopted edition and your Authority Having Jurisdiction (AHJ). Not a compliance certification. See the privacy & disclaimer page; the API stores nothing.