Agent Guide: arcgis-tables-forms

Quick-reference for tabular/attribute UIs on SDK 5.1. Read before building tables or forms.

Quick Decision Tree

1. Many rows, spreadsheet view? → arcgis-feature-table with reference-element pointing at the map.
2. Edit one feature's attributes? → arcgis-feature-form with layer + feature; save in arcgisSubmit.
3. Related table records? → RelationshipQuery + queryRelatedFeatures, id from layer.relationships.

Setup Checklist

• Set reference-element on the table, or its view stays null and selection never reaches the map.
• Filter the table with its own definitionExpression, not the layer's (that one filters the map too).
• Gate editingEnabled on layer.editingEnabled and capabilities.operations.supportsUpdate.
• Persist form values with layer.applyEdits inside arcgisSubmit; submit() alone saves nothing.
• Read related results as res[id]?.features ?? []: parents without related rows are not keys.

Anti-patterns (one-liner reminders)

• ❌ A table without reference-element expected to highlight on the map.
• ❌ A guessed relationshipId (error: "Unable to complete operation.").
• ❌ editingEnabled = true on a read-only service (accepted silently).
• ❌ The deprecated FeatureTable/FeatureForm widgets in new apps.
• ❌ await layer.load() "so columns appear": the table loads the layer itself.

Files in This Skill

• SKILL.md / SKILL.es.md — full guides
• references/api-detail.md — component + RelationshipQuery signatures
• references/examples.md — table / form / related-records
• references/pitfalls.md — extended troubleshooting
• scripts/snippet-feature-table.ts, snippet-related.ts