some context

app.R

@@ -22,6 +22,11 @@ ui <- page_sidebar(
   fillable = FALSE, # do not squeeze to vertical screen space
   tags$head(css),
   titlePanel("Demo App"),
+
+"This is a proof-of-principle for a simple chat-driven interface to dynamically explore geospatial data. 
+ ",
+
+
   card(
     layout_columns(
     textInput("chat",
@@ -66,6 +71,29 @@ ui <- page_sidebar(
       )
     ),
 
+    card(
+      card_header("Errata"),
+      markdown(
+"
+#### Credits
+
+Developed by Carl Boettiger, UC Berkeley, 2025.  BSD License.
+
+Data from the US Census and CDC's [Social Vulnerability Index](https://www.atsdr.cdc.gov/place-health/php/svi/index.html)
+
+#### Technical details
+
+The app is written entirely in R using shiny. The app will translate natural language queries in SQL code using
+a small open-weights language model. The SQL code is executed using the duckdb backend against cloud-native
+geoparquet snapshot of the Social Vulnerability Index hosted on Source Cooperative. Summary chart data are also
+computed in duckdb by streaming, providing responsive updates while needing minimal RAM or disk storage despite
+the large size of the data sources. 
+
+The map is rendered and updated using MapLibre with PMTiles, which provides responsive rendering for large feature sets.
+The PMTiles layer is also hosted on Source cooperative where it can be streamed efficiently.
+")
+    )
+
   ),
 
   sidebar = sidebar(
@@ -178,8 +206,8 @@ server <- function(input, output, session) {
     chart2 <- df |> 
       rename(social_vulnerability = y_axis) |>
       ggplot(aes(social_vulnerability)) +
-      geom_density(fill="darkred")  +
-      xlim(c(0,1)) +
+      geom_density(fill = "darkred")  +
+      xlim(c(0, 1)) +
       ggtitle("Vulnerability of selected areas")
 
     output$chart2 <- renderPlot(chart2)