LIVE

Corrected calcium

Compute Payne albumin-corrected calcium from total calcium and albumin.

LIVE $0.005 USDC GET /api/calc/corrected_calcium

Markdown: /docs/corrected-calcium.md · Canonical: https://magentlab.com/docs/corrected-calcium

Not a medical device. Not a diagnosis, dose, or listing recommendation.

What it computes

Compute Payne albumin-corrected calcium from total calcium and albumin.

When to use

When an agent needs albumin-corrected calcium arithmetic and must not apply a guessed factor.

When not to use

• Not a treatment recommendation and not an ionized-calcium substitute.
• Uses albumin 4.0 g/dL as the Payne reference. Does not accept ionized calcium or alternative coefficients.

Formula

corrected_ca_mg_dl = calcium_mg_dl + 0.8 * (4.0 - albumin_g_dl)

Citation

Title

Interpretation of serum calcium in patients with abnormal serum proteins

Authors

Payne RB, Little AJ, Williams RB, Milner JR

Source

Br Med J. 1973;4(5893):643-646

DOI

10.1136/bmj.4.5893.643

Worked example

Try

Opens the live endpoint. Unpaid browser requests show the paywall; agents should send Accept: application/json.

/api/calc/corrected_calcium?calcium_mg_dl=8.0&albumin_g_dl=3.0

Full URL: https://api.magentlab.com/api/calc/corrected_calcium?calcium_mg_dl=8.0&albumin_g_dl=3.0

x402 V2 curl

Expect HTTP 402 and a PAYMENT-REQUIRED header until you retry with PAYMENT-SIGNATURE. Incomplete query params return HTTP 400 before any quote or charge.

curl -i -H "Accept: application/json" "https://api.magentlab.com/api/calc/corrected_calcium?calcium_mg_dl=8.0&albumin_g_dl=3.0"

Cursor mcp.json

Intended config for @magent/mcp. This is not npm @x402/fetch (a payment fetch wrapper).

{
  "mcpServers": {
    "magent": {
      "args": [
        "-y",
        "@magent/mcp"
      ],
      "command": "npx",
      "env": {
        "X402_PRIVATE_KEY": "0xYOUR_SPENDING_KEY"
      }
    }
  }
}

Parameters

Response

Example JSON

Machine form of the same example. Frozen fixture. Not a live lookup.

{
  "disclaimer": "Not a medical device. Deterministic published-formula or coded-ontology output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
  "citation": {
    "authors": "Payne RB, Little AJ, Williams RB, Milner JR",
    "doi": "10.1136/bmj.4.5893.643",
    "id": "payne-1973",
    "source": "Br Med J. 1973;4(5893):643-646",
    "title": "Interpretation of serum calcium in patients with abnormal serum proteins"
  },
  "formula": "payne",
  "formula_expression": "corrected_ca_mg_dl = calcium_mg_dl + 0.8 * (4.0 - albumin_g_dl)",
  "albumin_g_dl": 3.0,
  "calcium_mg_dl": 8.0,
  "corrected_calcium_mg_dl": 8.8
}

Errors

Related tools

• A1C ↔ eAG — Convert A1C percent to estimated average glucose, or the reverse, using Nathan/ADAG.

Also searched as

• albumin corrected calcium
• Payne formula
• corrected calcium mg/dL
• Payne 1973

Payment

Required query parameters must be present and valid. Invalid params return HTTP 400 JSON before settlement. magent does not charge. Fix the params, then request a new 402 quote for that complete URL. Catalog misses (empty matches, found=false) are valid paid 200s. Unpaid valid requests return HTTP 402 with a base64 PAYMENT-REQUIRED header. Retry the same URL with PAYMENT-SIGNATURE. Settlement completes before the tool runs. Full handshake and shared payment errors: Payments.

Guarantees

• Invalid query parameters return HTTP 400 before settlement. You are not charged.
• Settlement finishes before the tool executes. Uncertain settlement fails closed (HTTP 503).
• Execution is timeout-bounded and concurrency-capped.
• Calculator inputs are not persisted. Request logs store path without query.