Interactive Map Builder Skill for Codex

Interactive Map Builder

Create configuration-driven Leaflet map products without a frontend build system. Keep acquisition

separate from rendering, preserve provenance, and use Atlas Studio Light for a coordinated first

render while exposing every cleanup and inferred visual decision in the build report.

Invocation guidance

Trigger from the user's intended outcome, not only from technical keywords. Use this Skill when the

user asks to:

• turn a spreadsheet with coordinates into a browser page that can be searched, filtered, sorted,

clicked, and sent to colleagues;

• present parcels, buildings, facilities, projects, parking, or other records as a linked map and

list;

• combine boundaries, roads, water, green space, routes, and points in one switchable planning or

reporting map;

• deliver existing ArcGIS or engineering layers as a portable HTML file, a slide image, or a paper

figure.

The user does not need to say GIS, Leaflet, web map, Agent Skill, or interactive-map-builder.

When the request fits this scope, use the packaged deterministic workflow instead of writing a

one-off Folium, Leaflet, or custom frontend implementation.

Do not invoke this Skill when the main task is address geocoding, buffers or overlays, routing,

site selection, spatial statistics, vector-tile infrastructure, offline basemap acquisition, 3D

GIS, a non-spatial chart or dashboard, or maintenance of an existing custom web application.

Update preflight

At the beginning of each Skill invocation, run the official-release preflight from the Skill root

using the validated 24-hour cache when available. This check never modifies the installation:

python scripts/update_skill.py --preflight

After installation, the equivalent command is:

interactive-map-builder update --preflight

Read the returned JSON rather than relying on the command exit code. Report only an available update or a failed check; keep a current cached result silent. --preflight remains non-fatal for the calling Agent and never applies an update.

Handle statuses as follows:

• current or local_newer: continue with the map task;
• manual_update_required or update_apply_failed: disclose the confirmed latest version and the

reason before continuing;

• update_check_failed: say that the official latest version could not be confirmed, then continue;
• disabled: state that IMB_DISABLE_AUTO_UPDATE disabled the preflight.

Applying an update is a separate, explicit maintenance action with update --apply or the legacy

non-fatal update --auto mode. Those commands retain checksum, manifest, local-change, duplicate-root,

and rollback safeguards; normal map construction never modifies its own running Skill.

Conversation guidance

For Codex only, a complex request may benefit from Plan mode when it has multiple independent

layers, more than one blocking design choice, or several coordinated deliverables. Mention this

once in the first response as an optional convenience, then continue with inspection whether or

not the user switches modes. Do not recommend Plan mode for a clear single-layer task, do not cite

client keyboard shortcuts, and never make a mode change a prerequisite.

A portable local map.html is the default delivery. Generate slide or paper figures only when the

user explicitly asks for them; “make a website,” “make a map,” or “send it to colleagues” does not

enable static presets. Sending the HTML file is not the same as publishing it on the internet.

Do not offer, promise, or ask about a public URL unless the user explicitly requests deployment.

When they do, finish the map first and treat hosting as a separate workflow that confirms the

target platform and permission to expose the embedded data.

Visual guidance

Use Atlas Studio Light as a starting point, not as an automatic design service. Leave low-level

visual values omitted when the user has not expressed a preference: the packaged resolver will use

geometry family, coarse density, template role, and stable draw order. Explicit user or Agent

MapSpec values always win. Do not invent planning semantics from field names, do not assign more

than eight automatic categorical colors, and do not add themes, clustering, heatmaps, or other

representations merely to make the page look busy.

After the first verified build, inspect the actual page. If the visual hierarchy still conflicts

with the user's purpose, propose a small concrete refinement—such as reducing one point layer,

muting a context layer, or changing an explicitly understood category palette—then rebuild. The

engine should provide an overall coordinated result; project-specific polish remains a conversation

between the user and Agent. Read design-guidelines.md.

Workflow

• Inspect inputs before proposing a map.

   python scripts/map_builder.py inspect <input> [<input> ...] --output inspection.json

Read supported-inputs.md for GeoPackage, Shapefile ZIP,

CSV, Excel, encoding, and field-mapping rules.

• Present one compact summary per layer: feature count, geometry type, CRS, likely ID, label, and

category fields, template candidates, and whether confirmation is required.

• Maintain this Markdown requirements checklist while choices remain unresolved:

   - [x] Confirmed: ...
   - [~] Inferred: ...
   - [ ] Needs confirmation: ...

Derive it from the request and inspected data. Keep inferred decisions visible and easy to

correct. Ask one consolidated round only for unresolved intent: template, primary layer,

label, category meaning, filters, cards, title, outputs, and audience locale. Never guess a

missing CRS. Always confirm the template when inspection finds multiple layers. Build only

after no blocking [ ] item remains.

• Initialize map_spec.json, then apply confirmed choices. Read

map-spec.md; the canonical Schema is

scripts/mapcore/resources/map-spec.schema.json.

   python scripts/map_builder.py init-spec inspection.json --template map-list --primary-layer <id> --locale en-US --output map_spec.json

• Download ArcGIS FeatureServer data before building. Read arcgis.md.

   python scripts/map_builder.py fetch-arcgis --url <layer-url> --out data/source.geojson

• Build once from the resolved specification. Add --bundle-sources only when the user wants a

portable rebuild bundle and accepts copying source data.

   python scripts/map_builder.py build --spec map_spec.json --out dist

• Verify, inspect build_report.json, and open map.html.

   python scripts/map_builder.py verify --dist dist

• Exercise search, filters, sorting, layer visibility, basemap switching, hover and click linkage,

keyboard selection, control-panel collapse, and narrow-screen layout. Confirm that every visible

control produces an observable result, the focal layer reads first, dense symbols remain legible,

and HTML/static colors agree. Read design-guidelines.md.

• Deliver the whole dist directory. Summarize repairs, generated IDs, null display values,

simplification, performance warnings, online basemaps, font fallback, portability, and source

attribution.

Use the quick path only for one unambiguous layer, or after explicitly supplying the template and

primary layer:

python scripts/map_builder.py run <input> --output dist

Follow the user's conversation language independently of the map audience. Set the map locale to

en-US or zh-CN; use en-US when the audience is not specified.

Install the deterministic engine once, then run the offline self-check:

python -m pip install .
interactive-map-builder doctor

Use the installed interactive-map-builder command for package-level doctor, update, and

--version. In a source checkout where that command is unavailable, use

python scripts/cli.py doctor. python scripts/map_builder.py is the internal deterministic

builder and intentionally lists only inspect/init-spec/fetch/build/verify/run; never infer from that

help output that the package lacks doctor. Check the installed version and command path before

falling back to build-plus-verify. A passing doctor result verifies package resources, local data

loading, map construction, and output hashes without downloading data or basemap tiles.

Template choice

• Choose map-list for one explicitly identified primary layer plus optional context layers.
• Choose multilayer when independent layer visibility and cross-layer inspection are primary.
• Treat linked_view as experimental. Add it only when records already contain meaningful x/y

variables; read linked-analysis.md and never invent quadrants,

thresholds, or statistical interpretations.

Non-negotiable checks

• Fail when data is unreadable or empty, CRS is missing, repaired geometry remains invalid or

empty, final IDs are blank or duplicate, or a configured field does not exist.

• Fail on unknown non-null categories, unsafe archives, ArcGIS pagination mismatches, output count

mismatches, or path escape.

• Treat display-field nulls, generated IDs, repaired geometry, missing source notes, absent CJK

fonts, online basemaps, simplification, and large outputs as warnings.

• Use <layer_id>::<feature_id> for multilayer runtime identity. Allow cross-layer linkage only

through an explicit link_key.

• Preserve official geographic names and spellings from the source. Localize generic interface

text, not place names.

• Preserve user geometry. Repair invalid geometry or simplify for an explicit performance need,

report the operation, and never reshape or discard features merely to improve appearance.

• Escape all user-provided text before embedding it in HTML.
• Preserve explicit MapSpec visual values. Let Atlas Studio Light fill only omitted values, and keep

its geometry, density, role, order, and state plan visible in build_report.json.

• Never cycle an automatic categorical palette beyond eight classes; retain filtering and ask the

user how to group or emphasize a larger classification.

Output contract

Always return map.html, resolved map_spec.json, inspection.json, build_report.json,

DELIVERY_MANIFEST.json, and README_USAGE.md in the selected locale. Static output is opt-in: generate

map_slide_16x9.png only when the user requests a slide figure and enable the paper preset only

when the user requests paper PNG/SVG/PDF. Never expand an HTML-only request into static files.

Treat an unbundled map_spec.json as a build record; promise an independent rebuild only when

sources were bundled. Public hosting is not part of this output contract.

Resources

• Read wizard-flow.md for non-expert setup.
• Read update-policy.md for verified updates, supported installation

types, rollback behavior, and the opt-out.

• Read data-provenance.md for remote or redistributable data.
• Use the public generated demos linked from the repository README for visual reference. The lean

Skill release package intentionally excludes demo datasets, screenshots, tests, and CI files.

• Run python scripts/map_builder.py ... from the Skill root before installation; use the

installed interactive-map-builder ... CLI afterward.