diff --git a/dependency-graph.js b/dependency-graph.js
index b1fae18b2c..ad5b8cbb9f 100644
--- a/dependency-graph.js
+++ b/dependency-graph.js
@@ -8,7 +8,9 @@
    - an element with id "dependency-graph-page" gets a folded labeled graph of every div on its page;
    - an element with id "dependency-graph-site" gets one tree of every div on the site, and an
      element with id "dependency-graph-all" and a data-json attribute (comma-separated URLs of
-     several sites' dependency-graph.json) gets one tree of all those sites together.
+     several sites' dependency-graph.json) gets one tree of all those sites together,
+     and says how many of its boxes each site defines.  Name this site's own graph by the
+     relative URL "dependency-graph.json", so that a PR preview joins its own graph, not main's.
      These have hundreds of nodes, so their boxes carry no text: the kind and title show as hovertext. */
 (function () {
   "use strict";
@@ -210,8 +212,13 @@
     var edges = g.edges.filter(function (e) { return ids[e[0]] && ids[e[1]]; }).map(function (e) { return [e[1], e[0]]; });
     var levels = layers(keys, nodes, uses), kinds = {};
     keys.forEach(function (k) { kinds[nodes[k].kind] = 1; });
+    /* A tree joining several sites (g.site is "") says how many boxes each site defines. */
+    var bySite = {}, parts = [];
+    keys.forEach(function (k) { bySite[nodes[k].site] = (bySite[nodes[k].site] || 0) + 1; });
+    if (!g.site) Object.keys(bySite).sort().forEach(function (s) { parts.push(bySite[s] + " from " + s); });
     var p = document.createElement("p");
-    p.textContent = keys.length + " definitions and results, " + edges.length + " dependencies, " + levels.length + " levels.";
+    p.textContent = keys.length + " definitions and results" + (parts.length ? " (" + parts.join(", ") + ")" : "") +
+      ", " + edges.length + " dependencies, " + levels.length + " levels.";
     host.appendChild(p);
     host.appendChild(legend(kinds, true));
     var s = document.createElement("div");
diff --git a/dependency-tree.qmd b/dependency-tree.qmd
index b3e0ec68b2..478fdc134a 100644
--- a/dependency-tree.qmd
+++ b/dependency-tree.qmd
@@ -30,5 +30,5 @@ This tree joins both sets of notes:
 a box sits below each definition and [theorem](https://morrison-lab.github.io/mcs/proof-writing.html#def-theorem) it uses, in either one,
 and hovering over a box also shows which notes it is in.
 
-::: {#dependency-graph-all data-json="https://morrison-lab.github.io/mcs/dependency-graph.json,https://morrison-lab.github.io/mds/dependency-graph.json"}
+::: {#dependency-graph-all data-json="https://morrison-lab.github.io/mcs/dependency-graph.json,dependency-graph.json"}
 :::
diff --git a/lychee.toml b/lychee.toml
index ba16f05bd6..1d02f0e444 100644
--- a/lychee.toml
+++ b/lychee.toml
@@ -20,7 +20,7 @@ timeout = 20
 exclude = [
   # Not a link: the data-json attribute of the joined tree in dependency-tree.qmd,
   # a comma-separated list of graph files that lychee reads as one URL (each file is live)
-  "^https://morrison-lab\\.github\\.io/mcs/dependency-graph\\.json,https://morrison-lab\\.github\\.io/mds/dependency-graph\\.json$",
+  "^https://morrison-lab\\.github\\.io/mcs/dependency-graph\\.json,dependency-graph\\.json$",
   "https://github.com/YOUR-USERNAME/.*",
   "https://YOUR-USERNAME.github.io/.*",
   "https://your-username.github.io/.*",