# MAP

Status: LIVE
Price: $0.005 USDC
`GET /api/calc/map`
HTML: https://magentlab.com/docs/map
Markdown: https://magentlab.com/docs/map.md

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

## What it computes

Compute conventional estimated mean arterial pressure from cuff systolic and diastolic pressures.

## When to use

When an agent needs the 1/3 pulse-pressure MAP estimate and must not invent a cuff MAP.

## When not to use

- Not a treatment target. This is the conventional 1/3 pulse-pressure estimate from cuff pressures, not an invasive aortic mean.
- Does not apply arterial-line averaging, form-factor corrections, or blood-pressure treatment thresholds.

## Formula

```
MAP_mm_hg = diastolic_mm_hg + (systolic_mm_hg - diastolic_mm_hg) / 3
```

## Citation

Systolic and diastolic blood pressure, pulse pressure, and mean arterial pressure as predictors of cardiovascular disease risk in men
Sesso HD, Stampfer MJ, Rosner B, et al.
Hypertension. 2000;36(5):801-807
DOI: [10.1161/01.HYP.36.5.801](https://doi.org/10.1161/01.HYP.36.5.801)

## Worked example

### SBP 120, DBP 80

Given: `diastolic_mm_hg=80, systolic_mm_hg=120`

1. pulse_pressure = 120 − 80 = 40
2. MAP = 80 + 40 / 3 = 93.333… → 93.3


## Parameters

- `systolic_mm_hg` (number, required): Cuff systolic blood pressure in mm Hg (50-250).
- `diastolic_mm_hg` (number, required): Cuff diastolic blood pressure in mm Hg (20-160). Must be less than systolic.

## Bulk (POST)

POST the same path with a JSON items array. Price is n times the GET unit. Invalid items return HTTP 400 before settlement.

Method: `POST /api/calc/map`
Max items: 25
Price: unit_amount * n (unit 5000 atomic)
Status: PREVIEW

- 1 to 25 items. Each item uses the same keys as the GET query parameters.
- The first invalid item fails the whole request (index in the 400 JSON). You are not charged.
- HTTP 200 is {count, path, items}. Each items[i] is the GET 200 body for that row.
- Catalog misses (empty matches, found=false) stay paid 200s inside that slot.
- x402 resource URL is this path plus n and body_sha256. Browsers that prefer text/html get the same paywall as GET; Pay retries POST with the same items.

Example request:

```json
{
  "items": [
    {
      "diastolic_mm_hg": "80",
      "systolic_mm_hg": "120"
    },
    {
      "diastolic_mm_hg": "80",
      "systolic_mm_hg": "120"
    }
  ]
}
```

Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/map

Example 200:

```json
{
  "count": 2,
  "path": "/api/calc/map",
  "items": [
    {
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "citation": {
        "authors": "Sesso HD, Stampfer MJ, Rosner B, et al.",
        "doi": "10.1161/01.HYP.36.5.801",
        "id": "sesso-2000",
        "source": "Hypertension. 2000;36(5):801-807",
        "title": "Systolic and diastolic blood pressure, pulse pressure, and mean arterial pressure as predictors of cardiovascular disease risk in men"
      },
      "formula": "map",
      "formula_expression": "MAP_mm_hg = diastolic_mm_hg + (systolic_mm_hg - diastolic_mm_hg) / 3",
      "diastolic_mm_hg": 80.0,
      "map_mm_hg": 93.3,
      "pulse_pressure_mm_hg": 40.0,
      "systolic_mm_hg": 120.0
    },
    {
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "citation": {
        "authors": "Sesso HD, Stampfer MJ, Rosner B, et al.",
        "doi": "10.1161/01.HYP.36.5.801",
        "id": "sesso-2000",
        "source": "Hypertension. 2000;36(5):801-807",
        "title": "Systolic and diastolic blood pressure, pulse pressure, and mean arterial pressure as predictors of cardiovascular disease risk in men"
      },
      "formula": "map",
      "formula_expression": "MAP_mm_hg = diastolic_mm_hg + (systolic_mm_hg - diastolic_mm_hg) / 3",
      "diastolic_mm_hg": 80.0,
      "map_mm_hg": 93.3,
      "pulse_pressure_mm_hg": 40.0,
      "systolic_mm_hg": 120.0
    }
  ]
}
```

## Response fields

- `formula` (string): map
- `formula_expression` (string): Exact expression used
- `systolic_mm_hg` (number): Systolic pressure used
- `diastolic_mm_hg` (number): Diastolic pressure used
- `pulse_pressure_mm_hg` (number): Systolic minus diastolic, mm Hg
- `map_mm_hg` (number): Estimated MAP in mm Hg, 1 decimal
- `citation` (object): Sesso 2000 Hypertension citation
- `disclaimer` (string): Not-a-device notice

## Example JSON

Frozen fixture. Not a live lookup.

```json
{
  "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
  "citation": {
    "authors": "Sesso HD, Stampfer MJ, Rosner B, et al.",
    "doi": "10.1161/01.HYP.36.5.801",
    "id": "sesso-2000",
    "source": "Hypertension. 2000;36(5):801-807",
    "title": "Systolic and diastolic blood pressure, pulse pressure, and mean arterial pressure as predictors of cardiovascular disease risk in men"
  },
  "formula": "map",
  "formula_expression": "MAP_mm_hg = diastolic_mm_hg + (systolic_mm_hg - diastolic_mm_hg) / 3",
  "diastolic_mm_hg": 80.0,
  "map_mm_hg": 93.3,
  "pulse_pressure_mm_hg": 40.0,
  "systolic_mm_hg": 120.0
}
```

## Errors

- HTTP 400 `invalid_systolic_bp`: systolic_mm_hg or systolic_bp_mm_hg must be a number from 50 to 250. Returned before settlement; you are not charged.
- HTTP 400 `invalid_diastolic_bp`: diastolic_mm_hg must be a number from 20 to 160. Returned before settlement; you are not charged.
- HTTP 400 `invalid_pulse_pressure`: diastolic_mm_hg must be less than systolic_mm_hg. Returned before settlement; you are not charged.
- HTTP 400 `invalid_items`: POST body must be a JSON object with only an items array Returned before settlement; you are not charged.
- HTTP 400 `invalid_item_count`: items must be an array of 1 to 25 objects Returned before settlement; you are not charged.
- HTTP 400 `invalid_item`: each items entry must be a JSON object Returned before settlement; you are not charged.
- HTTP 402 `payment_required`: Missing or invalid PAYMENT-SIGNATURE; decode the PAYMENT-REQUIRED header
- HTTP 409 `payment_in_progress`: The same authorization nonce is already being settled; retry shortly
- HTTP 429 `rate_limited`: Too many requests from this client
- HTTP 503 `settlement_uncertain`: Settlement is unconfirmed; retry with the same PAYMENT-SIGNATURE
- HTTP 503 `settle_failed`: Settlement failed; retry with the same PAYMENT-SIGNATURE shortly
- HTTP 503 `facilitator_unavailable`: Payment facilitator unavailable
- HTTP 503 `facilitator_misconfigured`: Payment facilitator is not configured
- HTTP 503 `facilitator_unauthorized`: Payment facilitator rejected credentials
- HTTP 503 `ledger_unavailable`: Payment ledger unavailable
- HTTP 503 `payment_unavailable`: Payment processing unavailable

## Related tools

- [BMI](https://magentlab.com/docs/bmi) — Compute Keys/Quetelet body-mass index from height and weight, plus a WHO adult band.
- [QTc](https://magentlab.com/docs/qtc) — Compute heart-rate-corrected QT using Bazett or Fridericia. The formula argument is required.

## Also searched as

- mean arterial pressure
- MAP
- estimated MAP
- cuff MAP
- 1/3 pulse pressure MAP

## 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.

- GET the tool with Accept: application/json (do not send Accept: text/html unless you want the human paywall).
- HTTP 402 means you have not paid. Decode the base64 PAYMENT-REQUIRED header. HTTP 503 is not a new quote.
- Sign EIP-3009 (scheme exact, assetTransferMethod eip3009) with validBefore = now + accepts[0].maxTimeoutSeconds (600 seconds). That window starts when you sign and must cover wallet confirmation plus CDP verify and settle. Magent retries transient facilitator 429/5xx before answering. Do not send upto or batch-settlement payloads; magent does not offer those schemes.
- Retry the same URL with PAYMENT-SIGNATURE (base64 JSON echoing accepted, payload, and extensions when present).
- Success is HTTP 200 JSON plus PAYMENT-RESPONSE. Settlement happens before the tool runs. HTTP 503 settlement_uncertain or settle_failed: retry the same PAYMENT-SIGNATURE. Mint a new nonce only after a new HTTP 402.

- offered `exact` on eip155:8453: Fixed-price USDC on Base. The buyer authorizes the advertised amount (EIP-3009). magent settles before the tool runs (paymentFlow upfront). extra.assetTransferMethod=eip3009 extra.paymentFlow=upfront.

- not offered `upto`: Not offered. Usage-based: buyer authorizes a ceiling, seller settles the actual amount after work. Reserved for a future metered tool. Not for current calculators or code search.
- not offered `batch-settlement`: Not offered. Payment-channel vouchers claimed later in batches. Not the same as POST {items} bulk (that is still exact).

Same-path POST {items} is still scheme exact: one EIP-3009 authorization for n times the GET unit. That is not x402 batch-settlement (payment channels / vouchers).

## Guarantees

- Invalid query parameters return HTTP 400 before settlement. You are not charged.
- Settlement finishes before the tool executes (paymentFlow upfront). Uncertain or failed settlement fails closed (HTTP 503). Retry the same PAYMENT-SIGNATURE.
- HTTP 402 is unpaid only. Do not sign a second authorization because of a 503.
- Execution is timeout-bounded and concurrency-capped.
- Calculator inputs are stored encrypted for allowlisted operators (Magent Console). They are not in public logs, SSH lookups, catalog, or rollups. Request logs store path without query.