value-domain-probelisted

# Value-domain probe Does a column the code coerces to a number actually hold numbers? ```bash python scripts/value_domain_probe.py --target ../zh-education-mcp python scripts/value_domain_probe.py --target . --dataset lernende --format json python scripts/coverage_run.py --probe value-domain --manifest manifest.json \ --repos-root ~/portfolio ``` Exit `0` numeric throughout a full read *or* every coercion guarded, `2` **finding**, `3` NOT MEASURED, `4` the checkout moved, `127` the harness could not run. ## Why `zh-education-mcp` against `www.bista.zh.ch`, 2026-08-03: the code called `int()` on `anzahl`. For small case counts the source publishes **`"1 bis 5"`** instead of a number, to protect the individuals behind them — beside `"NULL"` and empty cells. `int("1 bis 5")` raises, and the caller saw only «unerwarteter interner Fehler». Measured shares: **18.6 %** of 13 902 rows, **18.1 %** of 62 684, **1.0 %** of 35 903. A one-in-five chance of a crash is the endpoint's normal behaviour, and no fixture could show it: a fixture carries the rows somebody chose, and nobody chooses the suppressed ones. ## What it reads The same `schema_fields.toml`, the same declared `file` + `symbol`, the same fetch as `schema-field-probe` — imported, not re-implemented. Columns handed to `int()`/`float()` in three accepted shapes (direct, name-bound over one hop, wrapped when exactly one column is inside). `int(float(x))` is attributed to the **inner** call, the one that meets the