GeoToolCN
Copyright (c) 2025 Cohen — MIT License (see LICENSE)

The MIT license covers the code in this repository. The administrative
boundary data it ships (GeoToolCN/data/china.full.gtc, packages/go/data/,
and the npm tarball's data/) is derived from a third-party source and is
NOT covered by that license:

  Source:      DataV.GeoAtlas, 阿里云 DataV 地理小工具
               https://datav.aliyun.com/tools/atlas
  Fetched via: https://geo.datav.aliyun.com/areas_v3/bound (scripts/fetch_datav_geojson.py)
  Processing:  converted from GCJ-02 to WGS-84 with the standard single-step
               inverse (a ~0.6 m median, up to ~5 m systematic residual on
               every vertex), quantised to 1e-5 degree, re-encoded.

The provider's own notice on the GeoAtlas tool reads (verbatim, as
reproduced in Alibaba Cloud's DataV documentation and by third parties;
the tool page itself is a JavaScript shell):

    数据来源于高德开放平台，仅供学习交流使用，
    若有版权相关问题，请前往高德开放平台确认。

    "The data comes from the Amap (高德) Open Platform and is provided for
    learning and exchange only. For copyright questions, confirm with the
    Amap Open Platform."

That is: the boundaries originate with Amap, DataV republishes them for
learning and exchange, and neither Alibaba Cloud nor Amap has granted this
project any license to redistribute them. Nothing here grants you any
right to the data beyond what those providers' terms grant you directly.
Before relying on the data — and in particular before using it
commercially, redistributing it, or presenting it as an authoritative
depiction of administrative boundaries — obtain whatever permission the
Amap Open Platform terms require, and observe the laws on surveying and
mapping data that apply to you.

The boundaries are a convenience for geocoding, not a legal or official
statement of administrative divisions. Known limitations are listed in
README.md under 数据来源 / Data Source.
