Electrolytes / glucose · LIVE
A1C estimated average glucose (Nathan ADAG)
A1C ↔ eAG
Convert A1C percent to estimated average glucose, or the reverse, using Nathan/ADAG.
Markdown: /docs/a1c-eag.md · Canonical: https://magentlab.com/docs/a1c-eag
Not a medical device. Not a diagnosis, dose, or listing recommendation.
What it computes
Convert A1C percent to estimated average glucose, or the reverse, using Nathan/ADAG.
When to use
When an agent must apply 28.7×A1C−46.7 instead of inventing an eAG from training data.
When not to use
- Not a diagnosis. Provide exactly one of a1c_percent or eAG (mg/dL or mmol/L).
- Does not interpret a glucose meter log or diagnose diabetes.
Formula
eAG_mg_dl = 28.7 * A1C_percent - 46.7
Citation
- Authors
- Nathan DM, Kuenen J, Borg R, Zheng H, Schoenfeld D, Heine RJ
- Source
- Diabetes Care. 2008;31(8):1473-1478
Worked example
A1C 7.0 → eAG
Given:
a1c_percent=7.0
- eAG = 28.7 * 7.0 - 46.7 = 154.2 mg/dL
- mmol/L = 154.2 / 18
Also searched as
- Nathan ADAG
- A1C to eAG 28.7
- estimated average glucose
- HbA1c eAG
Try
Opens the live endpoint. Unpaid browser requests show the paywall; agents should send Accept: application/json.
/api/calc/a1c_eag?a1c_percent=7.0
Full URL: https://api.magentlab.com/api/calc/a1c_eag?a1c_percent=7.0
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/a1c_eag?a1c_percent=7.0"
Parameters
| Name | Type | Required | Description |
|---|---|---|---|
a1c_percent |
number | optional | HbA1c in percent (4-15). Provide this or an eAG, not both. |
eag_mg_dl |
number | optional | Estimated average glucose in mg/dL (50-500). |
eag_mmol_l |
number | optional | Estimated average glucose in mmol/L. Converted as mg/dL = mmol/L * 18. |
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.
- 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": [
{
"a1c_percent": "7.0"
},
{
"a1c_percent": "7.0"
}
]
}
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/a1c_eag",
"items": [
{
"direction": "a1c_to_eag",
"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": "Nathan DM, Kuenen J, Borg R, Zheng H, Schoenfeld D, Heine RJ",
"doi": "10.2337/dc08-0545",
"id": "nathan-2008",
"source": "Diabetes Care. 2008;31(8):1473-1478",
"title": "Translating the A1C assay into estimated average glucose values"
},
"formula": "nathan_adag",
"formula_expression": "eAG_mg_dl = 28.7 * A1C_percent - 46.7",
"eag_mg_dl": 154.2,
"a1c_percent": 7.0,
"eag_mmol_l": 8.6
},
{
"direction": "a1c_to_eag",
"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": "Nathan DM, Kuenen J, Borg R, Zheng H, Schoenfeld D, Heine RJ",
"doi": "10.2337/dc08-0545",
"id": "nathan-2008",
"source": "Diabetes Care. 2008;31(8):1473-1478",
"title": "Translating the A1C assay into estimated average glucose values"
},
"formula": "nathan_adag",
"formula_expression": "eAG_mg_dl = 28.7 * A1C_percent - 46.7",
"eag_mg_dl": 154.2,
"a1c_percent": 7.0,
"eag_mmol_l": 8.6
}
]
}
Response
| Field | Type | Description |
|---|---|---|
formula |
string | nathan_adag |
formula_expression |
string | Exact expression used |
direction |
string | a1c_to_eag or eag_to_a1c |
a1c_percent |
number | A1C %, 1 decimal |
eag_mg_dl |
number | eAG in mg/dL, 1 decimal |
eag_mmol_l |
number | eAG in mmol/L (mg/dL / 18), 1 decimal |
citation |
object | Nathan Diabetes Care 2008 |
disclaimer |
string | Not-a-device notice |
Example JSON
Machine form of the same example. Frozen fixture. Not a live lookup.
{
"direction": "a1c_to_eag",
"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": "Nathan DM, Kuenen J, Borg R, Zheng H, Schoenfeld D, Heine RJ",
"doi": "10.2337/dc08-0545",
"id": "nathan-2008",
"source": "Diabetes Care. 2008;31(8):1473-1478",
"title": "Translating the A1C assay into estimated average glucose values"
},
"formula": "nathan_adag",
"formula_expression": "eAG_mg_dl = 28.7 * A1C_percent - 46.7",
"eag_mg_dl": 154.2,
"a1c_percent": 7.0,
"eag_mmol_l": 8.6
}
Client errors (HTTP 400)
Invalid params return 400 without charge. Shared HTTP 402 and 503 meanings: Payments.
| HTTP | Code | When |
|---|---|---|
| 400 | invalid_a1c_input |
provide a1c_percent or eag_mg_dl/eag_mmol_l, not both Returned before settlement; you are not charged. |
| 400 | invalid_a1c |
a1c_percent must be a number from 4 to 15 Returned before settlement; you are not charged. |
| 400 | invalid_eag |
eag_mg_dl (50-500) or eag_mmol_l (2.8-27.8) 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. |
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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.