name: validate-geoparquet
description: "Validate and explain GeoParquet 2.0 vector files by checking local
geo metadata, native Parquet Geometry/Geography types, WKB, CRS, dimensions,
bounding boxes, footer statistics, and the GeoParquet 1.1 compatibility
boundary."
disable-model-invocation: true
metadata:
disco-role: operating
license: Apache 2.0
Validate GeoParquet
Use this skill when a user asks whether a Parquet file is GeoParquet, wants to
check the geo metadata, needs to inspect a native geometry logical type or
geospatial statistics, or is troubleshooting WKB, CRS, geometry_types,
bbox, edges, orientation, or epoch. It covers vector GeoParquet 2.0.
It is not a general-purpose writer, converter, package installer, benchmark
runner, or raster validator. For publication layout and external writer
selection, route to ../distribute-geoparquet/SKILL.md.
For the alpha raster proposal, route to
../parquet-raster/SKILL.md.
The bundled helpers are deliberately checkout-independent and offline by
default. They require only the relevant installed Python dependencies (normally
PyArrow and jsonschema; native fixture creation additionally uses
geoarrow-pyarrow). The verified CPU smoke baseline is pyarrow 25.0.1,
geoarrow-pyarrow 0.2.0, geopandas 1.1.4, and jsonschema 4.26.0, with
referencing imports succeeding. Its local example reports geo.version
2.0.0, native Geometry, and geo statistics. Probe the actual runtime before
relying on these versions. The repository described by the source evidence is a
specification and example suite, not an installable Python package; do not
claim that installing this skill installs a GeoParquet writer.
Conformance target
A GeoParquet 2.0 candidate has two coordinated contracts:
- Native Parquet geometry. Every geometry column is a root-level,
required or optional
BYTE_ARRAY annotated as native GEOMETRY or
GEOGRAPHY. It is not repeated, nested, a list, a map, or a struct. The
values use WKB and x,y axis order regardless of CRS axis declarations.
- Footer metadata. File key/value metadata has an exact
geo key whose
UTF-8 value is JSON. The object has version: "2.0.0", a non-empty
primary_column, and a non-empty columns object. Every geometry column is
listed with encoding: "WKB" and a geometry_types array.
Metadata alone is not enough: a plain binary WKB column carrying plausible
geo JSON is non-conformant GeoParquet 2.0. Conversely, native Parquet
geometry without the geo metadata block is useful native geospatial Parquet
but is not a self-described GeoParquet 2.0 file.
Read the detailed rules in references/vector-spec.md
and the schema and offline-validation boundary in
references/metadata-schema.md.
Operating procedure
1. Establish the claim
Record the intended version, each geometry column, whether this is a single file
or a partition, and whether GeoParquet 1.1 readers are required. Do not infer
format support from a filename, a successful generic Parquet open, or a writer
name. Preserve the exact tool and library versions used to create the file.
2. Inspect the footer before interpreting metadata
Run the bundled inspector from any working directory:
python /path/to/inspect_geoparquet.py data.parquet
For a strict gate, use --require-conformant --require-statistics. Review the
geo key, schema paths, physical types, definition/repetition levels, native
logical type JSON, row-group count, and every row-group's geospatial statistics.
The expected geometry leaf is root-level BYTE_ARRAY, max repetition level 0,
and native Geometry or Geography.
3. Validate the geo object locally
A metadata file may be the bare object or {"geo": {...}}:
python /path/to/validate_geo_metadata.py metadata.json
To validate a metadata file against a Parquet footer, use:
python /path/to/validate_geo_metadata.py metadata.json --parquet data.parquet
Passing data.parquet as the input extracts the footer geo value directly.
The default is local and does not fetch the PROJJSON schema. A non-zero exit
means the metadata or requested footer checks failed. Use
--allow-missing-statistics only when the report explicitly records that the
statistics gate was deferred; it does not turn absent statistics into verified
statistics. A supplied --schema is also localized offline if it contains a
remote $ref.
4. Reconcile metadata, logical types, and statistics
For every metadata geometry column, check that:
- the column exists as a root-level Parquet field and is WKB
BYTE_ARRAY;
- it is required or optional, never repeated or nested;
- its native logical type is
Geometry or Geography;
- the
primary_column names both a metadata entry and a native geometry field;
- the geometry type list is complete, unique, and dimension-suffixed correctly;
- known types match native
geospatial_types statistics, while [] means
unknown rather than “Point”;
- the file-level bbox is in the same CRS and contains every row-group extent;
- native statistics are present for the strict 2.0 inspection gate; and
- native CRS semantics agree with
geo.columns[*].crs, even when the two
representations are not byte-for-byte identical.
The local helper reports metadata-level CRS shape and footer facts, but it does
not resolve an authority registry or prove semantic CRS equivalence. Record
those as unresolved unless a separately approved CRS-aware check is available.
5. Apply the exact field rules
encoding is exactly WKB.
- Allowed base geometry types are
Point, LineString, Polygon,
MultiPoint, MultiLineString, MultiPolygon, and GeometryCollection.
Dimension suffixes are exactly Z, M, or ZM; Point Z is valid but
PointZ is not. Types must be unique and complete.
crs in GeoParquet metadata is inline PROJJSON or null, never an authority
string. If absent, the default is OGC:CRS84 (longitude, latitude on WGS84);
null means undefined or unknown. On the native logical type, CRS may be
inline PROJJSON, <authority>:<code> such as EPSG:4326, srid:<id>
(srid:0 means undefined/unknown), or projjson:<key_name>.
edges is one of planar, spherical, vincenty, thomas, andoyer, or
karney; absent means planar. orientation, when present, is only
counterclockwise and asserts counterclockwise exterior and clockwise
interior polygon rings.
bbox is 4 values for XY, 6 for XYZ, or 8 for XYZM, with minimums followed
by maximums (and RFC 7946 geographic ordering). A 5-element bbox is invalid;
M-only bounds cannot be expressed in this metadata field. epoch is an
optional decimal year for a dynamic CRS and is per column.
- The native logical type's geospatial statistics should expose geometry type
codes and x/y extents, with z/m extents when applicable. A supplied metadata
bbox must contain all row-group extents.
For a compact field reference, see
references/vector-spec.md. For schema-valid and
invalid examples, see references/metadata-schema.md.
6. Classify and recover
Classify the result as conformant candidate only when local metadata,
native schema, WKB/physical layout, and required statistics checks pass. Use
non-conformant for any required failure, especially metadata with no native
logical type, PointZ, duplicate geometry types, a five-element bbox, a string
metadata CRS, nested/repeated geometry, or mismatched statistics. Use not
verified when a full PROJJSON validation, CRS equivalence check, or required
statistics observation could not run. Do not relabel “not verified” as pass.
Follow references/inspection-workflow.md
for the complete decision sequence and
references/troubleshooting.md for bounded
recovery actions. Keep raw reports and review artifacts outside this runtime
skill tree.
Safe bundled helpers
All runtime files are linked here so they can be discovered without source
checkout assumptions:
scripts/validate_geo_metadata.py —
offline metadata validator; accepts bare/wrapped JSON or a Parquet footer and
returns non-zero for invalid metadata or failed requested footer checks.
scripts/inspect_geoparquet.py — emits a
JSON footer report with geo metadata, schema/logical-type facts, native
columns, and row-group statistics; non-conformant reports return non-zero.
scripts/write_minimal_geo_metadata.py
— writes an explicit one-row native fixture when geoarrow-pyarrow is
available, or a deliberate --plain non-native fixture for boundary tests.
scripts/make_wkb_fixture.py — writes a
deterministic WKB fixture for each supported base geometry and XY/XYZ/XYM/XYZM.
Each script supports --help, explicit paths, arbitrary current working
directories, and no network access. The fixture scripts refuse to overwrite an
existing output unless --force is supplied.
GeoParquet 1.1 compatibility boundary
GeoParquet 1.1 commonly stores WKB BYTE_ARRAY values with legacy geo
metadata and a bbox covering. That is a deliberate compatibility target for
older or heterogeneous readers, not a 2.0 label: it lacks the required native
GEOMETRY/GEOGRAPHY logical type. The compatibility guidance assumes a
geometry or geography column, WGS84 longitude/latitude (OGC:CRS84), and
planar or spherical edges respectively. Prefer a real 1.1 writer when that
reader matrix is mandatory, and validate the 1.1 artifact as 1.1 rather than
calling it 2.0. A native-type-only file without geo metadata is likewise not
full 2.0 GeoParquet.
Routing links