| name | carto-preview-builder-map |
| description | Preview an existing saved CARTO Builder map inline in the chat via the CARTO MCP server's load_builder_map tool. Use whenever the user references a saved Builder map — by URL, by ID, or by name (resolved via list_maps first). Renders a lightweight read-only preview (layers, basemap, viewport, popups, legend). Widgets, SQL parameters, map description, and other Builder-only features are NOT included; the user can click "Open in Builder" for the full experience. Triggers on "show me the X map", "open the Y map", "preview the Z map", and post-CLI-creation inline previews of a freshly-created map. Distinct from carto-create-builder-maps (CLI authoring), carto-render-inline-map (ad-hoc deck.gl spec), and carto-develop-app (developer app). |
| license | MIT |
carto-preview-builder-map
Renders a lightweight inline preview of an existing saved CARTO Builder map via the CARTO MCP server's load_builder_map tool. The user references the map (by URL, ID, or name); the agent locates it and loads it inline.
Tool contract. This skill consumes the load_builder_map and list_maps tools exposed by the CARTO MCP server. The tools' input shapes and access-control rules (the user must own, be shared on, or have public access to the map) are documented in the tool's own MCP description — read it via the MCP host's tool-inspector or by calling tools/list. This skill stays focused on routing, name → ID resolution, and setting expectations on the lightweight preview; it does NOT duplicate the tool's spec.
This skill assumes the CARTO MCP server is attached (the load_builder_map and list_maps tools are in your tool list) AND the host supports MCP Apps (Claude.ai, Claude Desktop, ChatGPT). If either is missing, see "Step 1 — detect what's available" below.
Step 1 — detect what's available
| Check | How |
|---|
load_builder_map and list_maps are callable | Both tool names appear in your tool list. |
| Host renders MCP Apps | Hosts that DO: Claude.ai, Claude Desktop, ChatGPT. Hosts that DON'T (Gemini CLI, Codex CLI, plain MCP Inspector, current MCPJam) execute the tool but only show a text confirmation — no map widget. |
| Setup | What to do |
|---|
| Tools present + host renders | Proceed normally. |
| Tools present + host doesn't render | Tell the user the host can't render maps inline; suggest opening the Builder URL directly. |
| Tools not present | The MCP server isn't attached. Tell the user; don't try to reconstruct the saved map from scratch. |
Resolution rules (URL / ID / name)
| User input | What to do |
|---|
Builder URL https://<workspace>.app.carto.com/builder/<mapId> | Extract <mapId> from the URL; call load_builder_map({ mapId }) directly. |
| Bare UUID | Call load_builder_map({ mapId }) directly. |
| Name / topic ("the retail-stores map", "my last week's accidents analysis") | Call list_maps({ search: "<topic>" }) first, then load by ID. See match handling below. |
For name-based lookup, use mine_only: true if the user said "my map". Default sort is updated_at desc — most recently edited first.
Match handling (after list_maps)
| Result | Action |
|---|
| 1 match | load_builder_map({ mapId: <id> }). Confirm to the user which map you're loading by name. |
| >1 matches | List names + dates + thumbnails. Ask the user to pick. Don't guess. |
| 0 matches | Tell the user no saved map matches. Offer carto-render-inline-map (view_map) as an ad-hoc alternative for the same data. |
Set expectations on the preview (always)
The preview is lightweight:
- ✓ Layers, basemap, viewport, popups, legend — exactly as configured in Builder.
- ✗ Widgets, SQL parameters, map description, AI agent configuration, and other Builder-only features are NOT included.
After loading, tell the user: "Loaded [name] as a lightweight preview. Widgets, SQL parameters, and the map description aren't included — click 'Open in Builder' in the rendered widget for the full experience." Set this expectation BEFORE the user asks why the preview looks different from the live Builder map.
Post-CLI-creation preview workflow
When the user creates a permanent map via carto maps create (from carto-create-builder-maps), the response is a mapId + Builder URL. With the MCP server attached, preview inline immediately:
# carto maps create returned { mapId: "abc-123", ... }
load_builder_map({ mapId: "abc-123" })
This is the fastest authoring loop: edit, save via CLI, preview inline via MCP, repeat. Especially useful for styling iterations.
Caveat: still the lightweight preview. If the user is debugging widgets or SQL parameters, they need the full Builder experience.
When to pick a different skill
- Ad-hoc visualization, no saved map exists →
carto-render-inline-map (view_map).
- Authoring / editing a permanent map →
carto-create-builder-maps (CLI).
- Building a from-scratch deck.gl app →
carto-develop-app.
Anti-patterns to avoid
- Reconstructing a saved map via
view_map instead of load_builder_map. If the user references an existing map, ALWAYS try list_maps + load_builder_map first. Re-rendering loses fidelity (saved layers, popups, legend) AND it's slower.
- Skipping
list_maps when the user references a map by name. Don't guess the ID. Search first.
- Promising widgets, SQL parameters, or map description in the preview. They're not rendered. Set expectations upfront.
- Picking the most-recent match silently when
list_maps returns multiple. Surface the choices and let the user pick.
