Source: https://guthlabs.ai/docs/instruments/parity-bit-simple-ecc-demo/implementation/

instrument implementation / implementation-contract

# Parity Bit / Simple ECC Demo implementation

A source-bound implementation contract for Parity Bit / Simple ECC Demo; 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**: t4-277

**Effect**: Computation or source lookup only

## Input and validation requirements

The arithmetic is well-defined for valid binary inputs, but the specification does not state invalid-input rejection behavior and does not identify the exact Hamming(7,4) matrix or bit-order convention. Non-binary input can yield an invalid parity result under JavaScript coercion, and alternative Hamming conventions can yield different codewords and syndromes.

## 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": {
    "bits": [
      0,
      0,
      0,
      0
    ],
    "parity_type": "even"
  },
  "expected_outputs": {
    "parity_bit": 0
  },
  "working": "XOR all bits: 0 XOR 0 = 0; 0 XOR 0 = 0; 0 XOR 0 = 0. Even-parity bit = 0. Total 1 bits after appending = 0, which is even."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/parity-bit-simple-ecc-demo/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/parity-bit-simple-ecc-demo/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/parity-bit-simple-ecc-demo/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-tranche4/tranche4-results.json`