network-accessibility-analysis

network-accessibility-analysis is a skill for Claude Code, Codex from muend/geoai-skills. It costs 99 tokens per session (1,508 once invoked), scanned A, original, MIT.

A guide to measuring how easily people can reach places through real streets, paths, and public-transport routes.

In plain words
What is it for?
It helps measure access to hospitals and other services, calculate travel areas and origin-to-destination times, assess walkability, and study coverage or fairness.
Why use it?
It replaces straight-line distance with travel costs that reflect roads, routes, transport modes, and realistic speeds.

Skill for Claude CodeCodex

Written for Claude Code and Codex: shipped in a Claude Code plugin, but also agents/openai.yaml present.

Part of the geoai plugin — 18 skills shipped together

Good fit It helps measure access to hospitals and other services, calculate travel areas and origin-to-destination times, assess walkability, and study coverage or fairness.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/muend/geoai-skills/network-accessibility-analysis
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add muend/geoai-skills --skill network-accessibility-analysis
Clone the repo
git clone --depth 1 https://github.com/muend/geoai-skills

Made for: Claude Code, Codex.

Or install geoai, the plugin that ships this one along with the rest of its 18 skills.

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.

agentmods badge for network-accessibility-analysis

README.md
[![agentmods](https://agentmods.dev/badge/skills/muend/geoai-skills/network-accessibility-analysis/github.svg)](https://agentmods.dev/skills/muend/geoai-skills/network-accessibility-analysis)
Your own site
<a href="https://agentmods.dev/skills/muend/geoai-skills/network-accessibility-analysis"><img src="https://agentmods.dev/badge/skills/muend/geoai-skills/network-accessibility-analysis/github.svg" alt="Measured on agentmods" height="20"></a>

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.

agentmods 80×15 button for network-accessibility-analysis

Your own site · 80×15
<a href="https://agentmods.dev/skills/muend/geoai-skills/network-accessibility-analysis"><img src="https://agentmods.dev/badge/skills/muend/geoai-skills/network-accessibility-analysis.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 99 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,508 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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00099 $0.01508
Opus 5 $0.00049 $0.00754
Sonnet 5 $0.00020 $0.00302
Haiku 4.5 $0.00010 $0.00151

Measured 10d ago against content hash 07553d4b6be7, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

network-accessibility-analysis 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 10d 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.

skills/network-accessibility-analysis/SKILL.md · 131 lines

How it starts

The opening of the file, as written. The whole thing — 131 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Network & Accessibility Analysis

Purpose: replace as-the-crow-flies guesswork with network-true travel costs, at the right scale and with honest assumptions about speeds and modes. First decision on every task: Euclidean distance is only acceptable as a declared approximation — flag it whenever you see it standing in for access.

Tool selection by scale

Scale Tool
Neighborhood-city, research flexibility OSMnx + NetworkX
City-region, many-to-many OD (>10⁴×10⁴) r5py (multimodal + transit w/ GTFS) or pandana (contraction-hierarchy speed)
Production routing service Valhalla / OSRM / OpenRouteService API
Proprietary stacks ArcGIS Network Analyst (script it headlessly)

NetworkX chokes on metro-scale many-to-many — don't loop shortest_path over thousands of origins; switch tools instead.

Graph construction (OSMnx)

import osmnx as ox

G = ox.graph_from_place("City, Country", network_type="drive")  # walk/bike/all
G = ox.add_edge_speeds(G)          # imputes from highway tags where maxspeed missing
G = ox.add_edge_travel_times(G)    # edge attr: travel_time (s)
G = ox.project_graph(G)            # metric CRS before any distance work
  • network_type matters: pedestrian analysis on a drive graph misses paths, stairs, plazas; driving on all uses footpaths. Match mode.
  • Imputed speeds are averages by road class — a systematic bias, not noise. State it; calibrate against known trips when stakes are high.
  • Keep the strongly connected component for routing (ox.truncate.largest_component(G, strongly=True)); orphan islands cause spurious infinities.
  • Snapping: origins/destinations map to nearest nodes/edges (ox.distance.nearest_nodes). Report the snap-distance distribution; a facility snapped 2 km away (riverside, gated area) silently corrupts results.

Core products

  • Isochrones / service areas: ego-graph by travel_time cutoff → alpha shape or buffered edge union around reached edges. Node-based convex hulls overstate coverage across rivers/highways — prefer edge-based polygons. Always label the assumptions: mode, speed model, cutoff.
  • OD matrix: many-to-many travel costs; the substrate for accessibility and location-allocation. For big matrices use pandana/r5py; store as Parquet with origin/destination IDs.
  • Closest facility: k-nearest by network cost (not Euclidean); report both the assigned facility and the cost.
  • Centrality: betweenness on travel_time (sampled k for big graphs — exact is O(nm)); edge betweenness ≈ through-traffic potential. Interpret as network structure, not observed traffic.

Read the full file on GitHub · 131 lines

Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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.

  1. 10d ago First seen · 131 lines · 99 tokens per session scan A 07553d4b6be7

Subscribe to this mod's changes

network-accessibility-analysis is a skill published in the GitHub repository muend/geoai-skills (15 stars, last pushed 6d ago), licensed MIT. It adds 99 tokens to every session and 1,508 once invoked, about $0.0005 per session on Opus 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.