API & MCP

Everything a person can do on Electron Configuration & Orbital Diagram, a program or AI agent can do with the same inputs and get the identical result.

HTTP API

• POST https://prooflineelectronconfig.usefulweb.app/api/v1/calculate – run Electron Configuration & Orbital Diagram
• GET https://prooflineelectronconfig.usefulweb.app/api/v1/tool – inputs, output schema, examples
• OpenAPI 3.1: /openapi.json · /openapi.yaml
• Errors: application/problem+json; 422 includes per-field errors.

Electron Configuration & Orbital Diagram

Type an element or an ion — Fe, Fe3+, Cu+, O2-, 26 or “iron” — and get its ground-state electron configuration in full and in noble-gas shorthand, the orbital box diagram drawn with Hund’s rule, the number of unpaired electrons (paramagnetic or diamagnetic), the electrons per shell and the quantum numbers of the last electron. The 20 elements whose measured ground state breaks the Aufbau rule, such as chromium, copper, palladium and gold, use the NIST configuration and say what the rule would have predicted. Part of the Proofline math notebook.

Example request

Iron

curl -X POST https://prooflineelectronconfig.usefulweb.app/api/v1/calculate -H 'content-type: application/json' -d '{"species":"Fe"}'

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://prooflineelectronconfig.usefulweb.app/mcp – protocol revisions 2026-07-28 (stateless) and 2025-11-25 / 2025-06-18 / 2025-03-26 (initialize handshake).
• Tools: proofline_electron_config
• Local stdio connector: node src/mcp-stdio.ts --tool=proofline-electron-config

{
  "mcpServers": {
    "proofline-electron-config": { "type": "http", "url": "https://prooflineelectronconfig.usefulweb.app/mcp" }
  }
}