What is raster-hexing?

A guide to converting raster files such as GeoTIFFs and Cloud-Optimized GeoTIFFs into H3 hexagons, a grid made of hexagonal map cells. It explains how source pixels are combined into each cell and how tiled rasters are combined first.

Use it to create raster workflows, choose reducers such as mean or sum, handle missing values and multiple tiles, and reprocess an existing raster.

It prevents incorrect results from using the wrong map resolution or pixel-combining method. It also provides the required workflow for creating a WGS84 cloud-optimized file before hexagon processing.

How boettiger-lab/data-workflows configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to boettiger-lab/data-workflows. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/boettiger-lab/data-workflows/main/.claude/skills/raster-hexing/SKILL.md

Clone the repo

git clone --depth 1 https://github.com/boettiger-lab/data-workflows

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/boettiger-lab/data-workflows/raster-hexing/github.svg)](https://agentmods.dev/skills/boettiger-lab/data-workflows/raster-hexing)

Your own site

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Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

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Per session 94 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 7,321 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits

NVIDIA SkillSpector pass 7 Sept 2026

How audits are shown

Origin original No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00094	$0.07321
Opus 5.5	$0.00038	$0.02928
Sonnet 5.5	$0.00019	$0.01464
Haiku 4.5	$0.00009	$0.00732

Measured 8d ago against content hash 16592548d422, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

raster-hexing scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 8d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.claude/skills/raster-hexing/SKILL.md · 275 lines

How it starts

The opening of the file, as written. The whole thing — 275 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Raster Hexing

Raster ingest produces COG + H3 hex only — no GeoParquet, no PMTiles. Always create the WGS84 COG first, then hex from that COG on NRP S3 (never from the original source URL).

Generating a raster workflow

cng-datasets raster-workflow \
  --dataset <name> --source-url <cog-url> --bucket <bucket> \
  --h3-resolution 8 --parent-resolutions "0" --value-column <band_name> \
  --hex-memory 32Gi --max-parallelism 61 \
  --output-dir catalog/<dataset>/k8s/<name>

Differences from vector:

Command: raster-workflow
Completions default to 122 (one per h0 cell). For a regional source pass --h0-cells (H3 base-cell numbers, e.g. CONUS 9,19,20,21,34,36) or --h0-subset (h0 grid positions, CONUS 12,14,20,50,71,78); both run 0–121, so the wrong one validates silently and builds other cells (datasets#191, #213)
Defaults: --h3-resolution 8, --parent-resolutions "0", --hex-memory 32Gi, --max-parallelism 61
--value-column — raster band name in output (default value)
--nodata — value(s) to exclude (auto from metadata); comma-separate multiple fill codes
--band <n> — required for a multi-band source; adds a preprocess-cog step that subsets the band (the hex step refuses an ambiguous multi-band input, datasets#214)
--hex-resampling — how pixels aggregate into each cell (sum/mean/mode/fractions/max/min, default mean). Picking the wrong one silently corrupts the data — see "Choosing the aggregation reducer" below. As important as --value-column.
Always creates a WGS84 COG on NRP S3 first; hex reads from that COG

Multi-tile rasters (e.g. multiple UTM zones): repeat --source-url. Adds preprocess-cog step that mosaics into one WGS84 COG:

cng-datasets raster-workflow --dataset wyoming/rap-arte \
  --source-url s3://.../rap_arte_zone12.tif \
  --source-url s3://.../rap_arte_zone13.tif \
  --bucket public-wyoming \
  --target-extent "-111.1,40.9,-104.0,45.0" --band 1 --value-column arte \
  --output-dir catalog/wyoming/k8s/rap-arte

Extra options: --target-extent "xmin,ymin,xmax,ymax" (EPSG:4326 clip), --target-resolution <degrees>, --band <n> (1-indexed), --output-cog-name <key>.

Read the full file on GitHub · 275 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

8d ago Changed · +14 lines · +2 tokens per session 16592548d422
24d ago Changed · +43 lines 89916da088fe
2mo ago Changed · +29 lines c65e821c4c3b
2mo ago First seen · 189 lines · 92 tokens per session scan A a061f20873ae

Subscribe to this mod's changes

raster-hexing is a skill published in the GitHub repository boettiger-lab/data-workflows (5 stars, last pushed 2d ago), licensed BSD-3-Clause. It adds 94 tokens to every session and 7,321 once invoked, about $0.0004 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Data and AI Scientific

raster-hexing next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
raster-hexingboettiger-lab/data-workflows	Skill	5	2d ago	BSD-3-Clause	A	94	Claude Code
arboretoK-Dense-AI/scientific-agent-skills	Skill	56k	4d ago	MIT	A	55	Claude Code, Codex
deepspot-mK-Dense-AI/scientific-agent-skills	Skill	56k	4d ago	MIT	A	70	Claude Code
torchdrugK-Dense-AI/scientific-agent-skills	Skill	56k	4d ago	MIT	A	64	Claude Code
pyhealthK-Dense-AI/scientific-agent-skills	Skill	56k	4d ago	MIT	A	84	Claude Code, Codex
nemo-mbridge-perf-expert-parallel-overlapNVIDIA/skills	Skill	3.9k	yesterday	Apache-2.0	A	56	Claude Code
ml-training-recipesOrchestra-Research/AI-Research-SKILLs	Skill	14k	26d ago	MIT	A	88	Claude Code

data-workflows: Skill for Claude Code