Create a custom embeddable knowledge card from your own data by specifying chart components directly. Returns card_id, image_url, webpage_url, and embed_url. Use List Default Schemas first to see available chart types and their required fields. Example body for a bar chart: {"components": [{"component_type": "header", "config": {"title": "Sales by Region"}}, {"component_type": "categorical_bar", "config": {"datasets": [{"label": "Revenue", "data": [{"x": "US", "y": 500}, {"x": "EU", "y": 300}]}]}}], "title": "Sales by Region", "source": "Internal Data"}