geojson

Inspect, validate, summarize, and troubleshoot GeoJSON files and payloads, including FeatureCollection checks, geometry counting, bbox generation, coordinate range review, and CRS-related safety guidance. Use when the user asks about GeoJSON, FeatureCollection, geometry validity, 坐标范围检查, bbox, GeoJSON summary, or GeoJSON debugging.

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

Practical Commands

Summarize a GeoJSON file

bash

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

Validate a GeoJSON file

bash

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

Summarize inline GeoJSON

bash

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.