Source: https://guthlabs.ai/docs/instruments/basal-insulin-carb-ratio-reference-education/implementation/

instrument implementation / implementation-contract

# Basal Insulin / Carb Ratio Reference (education) implementation

A source-bound implementation contract for Basal Insulin / Carb Ratio Reference (education); deployment and executable qualification remain separate.

Status: **VERIFIED_CLEAN**Lifecycle: **implementation-contract**

## Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

**Record owner**: Guth Instruments

**Lifecycle**: verified-clean

**Evidence ID**: t5-078

**Effect**: Computation or source lookup only

## Input and validation requirements

A zero insulin-to-carbohydrate ratio produces division by zero and an undefined bolus. The instrument should reject this input explicitly; returning a numeric result would be a safety-relevant failure of input validation.

## Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

## Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

````
{
  "inputs": {
    "carbs_g": 60,
    "insulin_carb_ratio_g_per_unit": 10,
    "current_bg_mg_per_dL": 180,
    "target_bg_mg_per_dL": 100,
    "correction_factor_mg_per_dL_per_unit": 50
  },
  "expected_outputs": {
    "illustrative_bolus_units": 7.6
  },
  "working": "Carb component = 60 / 10 = 6 units. Correction component = (180 - 100) / 50 = 80 / 50 = 1.6 units. Total = 6 + 1.6 = 7.6 units."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/basal-insulin-carb-ratio-reference-education/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/basal-insulin-carb-ratio-reference-education/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/basal-insulin-carb-ratio-reference-education/qualification/>)

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `VERIFIED_LEDGER.json`

- `evidence-tranche5/tranche5-results.json`