Source: https://guthlabs.ai/docs/instruments/metronome-click-track-export-tempo-map/implementation/

instrument implementation / implementation-contract

# Metronome Click Track Export (Tempo Map) implementation

A source-bound implementation contract for Metronome Click Track Export (Tempo Map); 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**: t6-083

**Effect**: Computation or source lookup only

## Input and validation requirements

The specification leaves beats-per-bar/time-signature semantics unspecified, creating different valid timestamp lists, and BPM = 0 causes an undefined division that must be rejected. The tempo-map boundary also requires explicit segment-switch semantics.

## 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": {
    "segments": [
      {
        "bpm": 120,
        "bar_count": 2
      }
    ],
    "beats_per_bar": 4,
    "initial_time_seconds": 0
  },
  "expected_outputs": {
    "timestamps_seconds": [
      0,
      0.5,
      1,
      1.5,
      2,
      2.5,
      3,
      3.5
    ],
    "total_duration_seconds": 4,
    "tempo_map_events": [
      {
        "time_seconds": 0,
        "bpm": 120
      }
    ]
  },
  "working": "One beat lasts 60/120=0.5 seconds. Each segment contains 2*4=8 beats. Segment duration=(60/120)*8=0.5*8=4 seconds. Starting at t=0, the eight clicks are t=0, 0+0.5=0.5, 1.0, 1.5, 2.0, 2.5, 3.0, and 3.5 seconds. The next segment boundary and total duration are t=4.0 seconds."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/metronome-click-track-export-tempo-map/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/metronome-click-track-export-tempo-map/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/metronome-click-track-export-tempo-map/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-tranche6/tranche6-results.json`