---
title: "mova-hard-cases-witness — Mova code model"
description: "Mova code model of tools/hard-cases/src/witness.rs: components with their labels, obernants and the model text."
url: "https://groupants.elamur.ai/free/en/mova/tools/hard-cases/src/witness.rs.groupant/"
---
Elamur: [Mova](https://md.mova.elamur.ai/free/en/) · [Dictionary](https://md.dictionary.elamur.ai/free/en/) · [Research](https://md.research.elamur.ai/free/en/) · **Groupants**

This page as HTML: <https://groupants.elamur.ai/free/en/mova/tools/hard-cases/src/witness.rs.groupant/>

# mova-hard-cases-witness

The groupant beside tools/hard-cases/src/witness.rs in the Mova repository: what the code computes, what it never does, how to go back from its outputs, its invariants, cost and checks.

## Facts

- **kind:** groupant
- **status:** partial source bound model
- **source:** [`tools/hard-cases/src/witness.rs`](https://github.com/ElamurAI/mova-free/blob/main/tools/hard-cases/src/witness.rs)
- **source SHA-256:** `461580a91b3b78e5…`
- **repository folder:** [`tools/hard-cases/src/witness.rs.groupant`](https://github.com/ElamurAI/mova-free/tree/main/tools/hard-cases/src/witness.rs.groupant)
- **repository commit:** `48f2e6f74146`

> **Implementation material.** A Mova code model describes this code at one source revision: partial models, finite checks and their stated scope. It is not a reviewed general exposition, and its labels are shown as written, never raised.

## Components

| component | label | where |
|---|---|---|
| **approximant** | partial | [Forward approximant](#forward-approximant) |
| **ast** | partial | `syntax.json` |
| **composition** | partial | [Composition](#composition) |
| **cost** | partial | [Cost](#cost) |
| **descriptant** | present | [Descriptant](#descriptant) |
| **invariant** | partial | [Invariant](#invariant) |
| **tests** | finite evidence | [Tests](#tests) |

## Obernants

The typed relations around the forward model: the behaviour complement (what the code never does), the reverse reconstruction (every input compatible with an output) and specialised views.

| id | type | label | where |
|---|---|---|---|
| `behavior_complement` | behavior_complement | partial source derived model | [behavior_complement](#behavior-complement) |
| `reverse_reconstruction` | reverse_reconstruction | partial source derived model | [reverse_reconstruction](#reverse-reconstruction) |

## Model text


### Descriptant

Stanza, Trankit and spaCy trf through the existing neural runner on a track's training trees under the shared GPU lease; # text attached only where id and every token form agree; agreed-input.conllu and parsers/out/*.conllu for the Eel's tree agreement. Source: `tools/hard-cases/src/witness.rs`.

### Forward approximant

if witness.json binds sha256(train) -> return it; else write in/ids.txt, in/tokens.txt; with flock(gpu_lock) run neural.py for the three parsers; align each output by index (same id and forms) -> keep the records all three align; write agreed input, filtered parser outputs, witness.json.

### Invariant

A record enters the agreed input only when all three parsers align on id and forms; parser output rows are unchanged except the inserted # text line; no witness is manufactured.

### Cost

Three neural parser runs (GPU); measured 38 s for 3 sentences including model loading.

### Composition

Feeds the Eel engine's agreement step (treeagree agree reads parsers/out). Parent hard-cases.

### behavior_complement

Does not run without the GPU lease (waits up to lease_wait_seconds), does not retry a failed parser, does not repair tokenization. Evidence status: source-derived model with finite checks, not a proof.

### reverse_reconstruction

The raw runner output stays in witness-run-<hash>/out; the filtered files plus the missing list recover which records each parser aligned.

### Tests

witness::tests (2026-11-04): text attached only to aligned records; red: a different tokenization and a wrong id do not align. Live: three sentences, all aligned; treeagree agree accepted the output. Finite fixtures and live samples; not a proof.