geojson（geojson 开发）

GeoJSON

Use this skill for practical GeoJSON inspection and validation.

This skill focuses on safe read-only analysis of GeoJSON structure and coordinates. For deterministic GIS conversion, reprojection, clipping, or raster/vector processing on files, hand off to qgis.

What This Skill Does

• Validate whether a JSON file or payload is plausible GeoJSON.
• Summarize top-level type, feature count, geometry types, and bbox.
• Flag obvious coordinate-range issues for longitude/latitude style data.
• Explain common GeoJSON mistakes such as malformed FeatureCollection, missing geometry, or wrong coordinate nesting.
• Recommend when EPSG:4326 assumptions are safe and when CRS clarification is required.

Standard Workflow

1. Confirm whether the input is a file path or inline JSON.
2. Parse the JSON and identify the top-level GeoJSON type.
3. Count features and geometry types.
4. Compute bbox from coordinates when possible.
5. Flag likely coordinate problems:

- out-of-range longitude/latitude - swapped lat,lon vs lon,lat - mixed geometry structures

1. If the user needs file transformation, reprojection, or editing, switch to qgis.

Practical Commands

Summarize a GeoJSON file

python3 {baseDir}/scripts/geojson_tool.py summary --file ./data/sample.geojson

Validate a GeoJSON file

python3 {baseDir}/scripts/geojson_tool.py validate --file ./data/sample.geojson

Summarize inline GeoJSON

python3 {baseDir}/scripts/geojson_tool.py summary --json '{"type":"Point","coordinates":[116.4074,39.9042]}'

Decision Rules

• Assume GeoJSON coordinates are lon,lat when they represent geographic positions unless the source clearly says otherwise.
• Do not assume every GeoJSON file is WGS84 just because it is GeoJSON; verify source context if precision matters.
• GeoJSON CRS metadata is effectively absent in modern practice; prefer explicit prose in the answer when CRS is uncertain.
• If distance or area analysis is needed, recommend reprojection to a projected CRS before measurement.
• Treat malformed but parseable data as suspect; report the issue instead of silently guessing.

What To Return

• Top-level GeoJSON type.
• Feature count when applicable.
• Geometry type counts.
• Bounding box when coordinates are present.
• A short note about likely CRS/coordinate-order assumptions.
• Specific validation errors or suspicious patterns when found.

When Not To Use

• Reverse geocoding or coordinates-to-address lookup: use geocode.
• WGS84-specific CRS reasoning: use wgs84.
• Deterministic GIS processing, conversion, reprojection, or clipping: use qgis.
• CesiumJS rendering logic: use cesium.

OpenClaw + ClawHub Notes

• Keep examples generic and portable.
• Do not hardcode private datasets, machine paths, or secrets.
• For clawhub.ai publication, keep examples standards-based and version/changelog updates semver-driven.

Reference Docs In This Skill

• Read {baseDir}/references/geojson-notes.md for common structures, nesting rules, and failure cases.