diff --git a/tools/all-specs.mjs b/tools/all-specs.mjs
new file mode 100644
index 0000000..8998db1
--- /dev/null
+++ b/tools/all-specs.mjs
@@ -0,0 +1,57 @@
+/**
+ * Every actor spec in the repository, collected once.
+ *
+ * Three things now need the same list — check-creatures validates it, make-portraits
+ * draws it, and mj-queue writes prompts for it — and this repository's one standing law
+ * is that a definition may not exist twice. The collection rule is a definition: a
+ * scenario cast is any exported array whose entries carry characteristics, so a new
+ * scenario is covered the day it is written rather than the day somebody remembers to
+ * add it to a list. That rule belongs in one place.
+ *
+ * `kind` is what buildActor will make of the spec: "agent" becomes a character actor,
+ * "npc" becomes an npc actor. It decides which portrait family a creature is drawn in
+ * and which prompt template it gets, so it is carried here rather than re-derived.
+ */
+import { NPCS, PREGENS } from "./content.mjs";
+import { ROSTER } from "./roster.mjs";
+
+/** Scenario modules whose casts join the list. */
+export const SCENARIOS = ["throughtrain", "starter", "lastadmission", "openday"];
+
+/**
+ * @returns {Promise<Array<{label: string, kind: "agent"|"npc", spec: object}>>}
+ *   every spec, in a stable order, each tagged with where it came from.
+ */
+export async function collectSpecs() {
+  const sources = [
+    { label: "content.mjs PREGENS", kind: "agent", specs: PREGENS },
+    { label: "content.mjs NPCS",    kind: "npc",   specs: NPCS },
+    { label: "roster.mjs ROSTER",   kind: "agent", specs: ROSTER }
+  ];
+
+  for (const s of SCENARIOS) {
+    const mod = await import(`./scenario-${s}.mjs`);
+    for (const [name, value] of Object.entries(mod)) {
+      if (Array.isArray(value) && value.some(x => x && typeof x === "object" && x.ch)) {
+        sources.push({ label: `scenario-${s}.mjs ${name}`, kind: "npc", specs: value });
+      }
+    }
+  }
+
+  const out = [];
+  for (const { label, kind, specs } of sources) {
+    for (const spec of specs) out.push({ label, kind, spec });
+  }
+  return out;
+}
+
+/** The same thing grouped, for callers that report per source. */
+export async function collectSources() {
+  const flat = await collectSpecs();
+  const byLabel = new Map();
+  for (const row of flat) {
+    if (!byLabel.has(row.label)) byLabel.set(row.label, { label: row.label, kind: row.kind, specs: [] });
+    byLabel.get(row.label).specs.push(row.spec);
+  }
+  return [...byLabel.values()];
+}
diff --git a/tools/check-creatures.mjs b/tools/check-creatures.mjs
index 70e26b1..c833601 100644
--- a/tools/check-creatures.mjs
+++ b/tools/check-creatures.mjs
@@ -14,30 +14,13 @@
  *
  *   node tools/check-creatures.mjs
  */
-import { NPCS, PREGENS } from "./content.mjs";
-import { ROSTER } from "./roster.mjs";
 import { readFile } from "node:fs/promises";
 import { validate, KNOWN_FIELDS } from "./creature-schema.mjs";
+import { collectSources } from "./all-specs.mjs";
 
-/* Scenario casts are collected by shape rather than by name: a cast is any exported
-   array whose entries carry characteristics. A new scenario is then covered the day it
-   is written instead of the day somebody remembers to add it here. */
-const SCENARIOS = ["throughtrain", "starter", "lastadmission", "openday"];
-
-const sources = [
-  { label: "content.mjs PREGENS", kind: "agent", specs: PREGENS },
-  { label: "content.mjs NPCS",    kind: "npc",   specs: NPCS },
-  { label: "roster.mjs ROSTER",   kind: "agent", specs: ROSTER }
-];
-
-for (const s of SCENARIOS) {
-  const mod = await import(`./scenario-${s}.mjs`);
-  for (const [name, value] of Object.entries(mod)) {
-    if (Array.isArray(value) && value.some(x => x && typeof x === "object" && x.ch)) {
-      sources.push({ label: `scenario-${s}.mjs ${name}`, kind: "npc", specs: value });
-    }
-  }
-}
+/* Scenario casts are collected by shape rather than by name — see all-specs.mjs, which
+   owns that rule now that make-portraits and mj-queue need the same list. */
+const sources = await collectSources();
 
 const problems = [];
 const seenKeys = new Map();