BeAM (bedtime minus AM glucose)

BeAM

Compute BeAM as bedtime glucose minus pre-breakfast (AM) glucose in mg/dL and return the Zisman 2016 analysis category (<0, 0-50, or >50).

LIVE $0.005 USDC GET /api/calc/beam

Markdown: /docs/beam.md · Canonical: https://magentlab.com/docs/beam

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

What it computes

Compute BeAM as bedtime glucose minus pre-breakfast (AM) glucose in mg/dL and return the Zisman 2016 analysis category (<0, 0-50, or >50).

When to use

When an agent needs the published BeAM difference and must not invent a 45 or 55 mg/dL cutoff, order prandial insulin, or diagnose diabetes.

When not to use

Not a medical device. magent does not diagnose diabetes or order prandial insulin.
Zisman 2016 analysis categories only: <0, 0-50, and >50 mg/dL. A 45–55 mg/dL range to consider additional intervention is not a hard cutoff in this tool.
Glucose is caller-supplied. magent does not measure capillary or laboratory glucose.

Formula

beam_mg_dl = bedtime_glucose_mg_dl - am_glucose_mg_dl; mmol/L × 18 → mg/dL; band <0 if beam_mg_dl < 0, 0-50 if 0 <= beam_mg_dl <= 50, >50 if beam_mg_dl > 50

Citation

Title: BeAM value: an indicator of the need to initiate and intensify prandial therapy in patients with type 2 diabetes mellitus receiving basal insulin
Authors: Zisman A, Morales F, Stewart J, Stuhr A, Vlajnic A, Zhou R
Source: BMJ Open Diabetes Res Care. 2016;4(1):e000171
DOI: 10.1136/bmjdrc-2015-000171

Worked example

Bedtime 180 mg/dL, AM 120 mg/dL

Given: am_glucose_mg_dl=120bedtime_glucose_mg_dl=180

BeAM = 180 − 120 = 60.0 mg/dL
60.0 > 50 → band >50. Not a prandial insulin order.

Bedtime 10.0 mmol/L, AM 6.67 mmol/L

Given: am_glucose_mmol_l=6.67bedtime_glucose_mmol_l=10.0

mg/dL = 10.0 × 18 = 180.0; 6.67 × 18 = 120.06
BeAM = 180.0 − 120.06 = 59.94 → 59.9 mg/dL, band >50

Also searched as

BeAM value
bedtime minus AM glucose
BeAM Zisman
bedtime AM differential
pre-breakfast glucose gap
BeAM type 2 diabetes
basal insulin BeAM

Try

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

/api/calc/beam?bedtime_glucose_mg_dl=180&am_glucose_mg_dl=120

Full URL: https://api.magentlab.com/api/calc/beam?bedtime_glucose_mg_dl=180&am_glucose_mg_dl=120

Call

Expect HTTP 402 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/beam?bedtime_glucose_mg_dl=180&am_glucose_mg_dl=120"

Parameters

Name	Type	Required	Description
`bedtime_glucose_mg_dl`	number	optional	Bedtime glucose in mg/dL (40-600). Provide this or bedtime_glucose_mmol_l, not both. Independent of the AM unit.
`bedtime_glucose_mmol_l`	number	optional	Bedtime glucose in mmol/L (2.2-33.3). Converted as mg/dL = mmol/L × 18 (same factor as HOMA-IR). Provide this or bedtime_glucose_mg_dl, not both.
`am_glucose_mg_dl`	number	optional	Pre-breakfast (AM) glucose in mg/dL (40-600). Provide this or am_glucose_mmol_l, not both. Independent of the bedtime unit.
`am_glucose_mmol_l`	number	optional	Pre-breakfast (AM) glucose in mmol/L (2.2-33.3). Converted as mg/dL = mmol/L × 18. Provide this or am_glucose_mg_dl, not both.

Bulk (POST)

POST the same path with a JSON items array. The first item is the GET unit; each additional item is $0.002. Invalid items return HTTP 400 before settlement.

POST /api/calc/beam Max 25 unit_amount + extra_item_amount * (n - 1) extra $0.002 PREVIEW

1 to 25 items. Each item uses the same keys as the GET query parameters.
POST of 1 item costs the same as GET. Lists longer than 25: chunk into multiple POSTs. Extra items still execute; do not pad dummy rows.
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 (fixture)

{
  "items": [
    {
      "am_glucose_mg_dl": "120",
      "bedtime_glucose_mg_dl": "180"
    },
    {
      "am_glucose_mg_dl": "120",
      "bedtime_glucose_mg_dl": "180"
    }
  ]
}

Open bulk paywall →

Opens a two-item fixture on the API host. Unpaid browsers get the same MetaMask paywall as GET; Pay retries POST with those items.

Example 200 (fixture)

{
  "count": 2,
  "path": "/api/calc/beam",
  "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": "Zisman A, Morales F, Stewart J, Stuhr A, Vlajnic A, Zhou R",
        "doi": "10.1136/bmjdrc-2015-000171",
        "id": "zisman-2016",
        "pmid": "27110368",
        "source": "BMJ Open Diabetes Res Care. 2016;4(1):e000171",
        "title": "BeAM value: an indicator of the need to initiate and intensify prandial therapy in patients with type 2 diabetes mellitus receiving basal insulin"
      },
      "formula": "beam",
      "formula_expression": "beam_mg_dl = bedtime_glucose_mg_dl - am_glucose_mg_dl; mmol/L × 18 → mg/dL; band <0 if beam_mg_dl < 0, 0-50 if 0 <= beam_mg_dl <= 50, >50 if beam_mg_dl > 50",
      "beam_band": ">50",
      "am_glucose_mg_dl": 120.0,
      "beam_mg_dl": 60.0,
      "bedtime_glucose_mg_dl": 180.0
    },
    {
      "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": "Zisman A, Morales F, Stewart J, Stuhr A, Vlajnic A, Zhou R",
        "doi": "10.1136/bmjdrc-2015-000171",
        "id": "zisman-2016",
        "pmid": "27110368",
        "source": "BMJ Open Diabetes Res Care. 2016;4(1):e000171",
        "title": "BeAM value: an indicator of the need to initiate and intensify prandial therapy in patients with type 2 diabetes mellitus receiving basal insulin"
      },
      "formula": "beam",
      "formula_expression": "beam_mg_dl = bedtime_glucose_mg_dl - am_glucose_mg_dl; mmol/L × 18 → mg/dL; band <0 if beam_mg_dl < 0, 0-50 if 0 <= beam_mg_dl <= 50, >50 if beam_mg_dl > 50",
      "beam_band": ">50",
      "am_glucose_mg_dl": 120.0,
      "beam_mg_dl": 60.0,
      "bedtime_glucose_mg_dl": 180.0
    }
  ]
}

Response

Field	Type	Description
`formula`	string	beam
`formula_expression`	string	Exact expression used
`bedtime_glucose_mg_dl`	number	Bedtime glucose in mg/dL (mmol/L × 18 when supplied as mmol/L), 1 decimal
`am_glucose_mg_dl`	number	Pre-breakfast glucose in mg/dL (mmol/L × 18 when supplied as mmol/L), 1 decimal
`beam_mg_dl`	number	BeAM in mg/dL (bedtime minus AM), 1 decimal
`beam_band`	string	Zisman 2016 analysis category: <0, 0-50, or >50 mg/dL. 0 and 50 are 0-50. Not a 45 or 55 cutoff.
`citation`	object	Zisman et al. 2016 citation
`disclaimer`	string	Not-a-device notice

Example JSON

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

{
  "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": "Zisman A, Morales F, Stewart J, Stuhr A, Vlajnic A, Zhou R",
    "doi": "10.1136/bmjdrc-2015-000171",
    "id": "zisman-2016",
    "pmid": "27110368",
    "source": "BMJ Open Diabetes Res Care. 2016;4(1):e000171",
    "title": "BeAM value: an indicator of the need to initiate and intensify prandial therapy in patients with type 2 diabetes mellitus receiving basal insulin"
  },
  "formula": "beam",
  "formula_expression": "beam_mg_dl = bedtime_glucose_mg_dl - am_glucose_mg_dl; mmol/L × 18 → mg/dL; band <0 if beam_mg_dl < 0, 0-50 if 0 <= beam_mg_dl <= 50, >50 if beam_mg_dl > 50",
  "beam_band": ">50",
  "am_glucose_mg_dl": 120.0,
  "beam_mg_dl": 60.0,
  "bedtime_glucose_mg_dl": 180.0
}

Client errors (HTTP 400)

Invalid params return 400 without charge. Shared HTTP 402 and 503 meanings: Payments.

HTTP	Code	When
400	`invalid_beam`	BeAM needs bedtime and pre-breakfast glucose (each as mg/dL or mmol/L), as used in Zisman 2016. Returned before settlement; you are not charged.
400	`invalid_bedtime_glucose`	bedtime_glucose_mg_dl (40-600) or bedtime_glucose_mmol_l (2.2-33.3) is required. Returned before settlement; you are not charged.
400	`invalid_am_glucose`	am_glucose_mg_dl (40-600) or am_glucose_mmol_l (2.2-33.3) is required. Returned before settlement; you are not charged.
400	`invalid_items`	POST body must be a JSON object with only an items array Returned before settlement; you are not charged.
400	`invalid_item_count`	items must be an array of 1 to 25 objects Returned before settlement; you are not charged.
400	`invalid_item`	each items entry must be a JSON object Returned before settlement; you are not charged.

Related tools

HOMA-IR — Compute the Matthews 1985 HOMA-IR approximation from fasting plasma glucose and insulin.
A1C ↔ eAG — Convert A1C percent to estimated average glucose, or the reverse, using Nathan/ADAG.
Bang diabetes screening — Sum the Bang 2009 Table 2 development screening score for undiagnosed diabetes and return high_risk when the total is ≥5.

Payment

Unpaid requests return HTTP 402 even if query parameters or POST items are missing or invalid, so CDP and agents can index the path. After a PAYMENT-SIGNATURE, 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. HTTP 503 is not a new quote: retry the same PAYMENT-SIGNATURE. Full handshake and shared payment errors: Payments. Stdio MCP: /docs/mcp.

Guarantees

HTTP 402 is unpaid, including a missing query. After PAYMENT-SIGNATURE, invalid parameters return HTTP 400 before settlement. You are not charged. HTTP 402 never includes the tool JSON.
exact: settlement finishes before the tool (paymentFlow upfront). batch-settlement: verify/deposit before the tool; chargedCumulativeAmount commits after HTTP 2xx. 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.