diff --git a/src/application/SourceLimitations.ts b/src/application/SourceLimitations.ts
index 5c62cf3883..2f40961f82 100644
--- a/src/application/SourceLimitations.ts
+++ b/src/application/SourceLimitations.ts
@@ -25,6 +25,13 @@ export const sourceLimitationKey = ({
     limitation,
   ]);
 
+/** Provider/text identity shared by rendering and composed-workflow budgets. */
+export const sourceLimitationGroupKey = ({
+  provider,
+  limitation,
+}: Pick<SourceLimitation, "provider" | "limitation">): string =>
+  JSON.stringify([provider.id, provider.name, provider.version, limitation]);
+
 /** Render unique source caveats without losing their provider or operation. */
 export const renderSourceLimitations = (
   limitations: readonly SourceLimitation[],
@@ -38,12 +45,7 @@ export const renderSourceLimitations = (
     }
   >();
   for (const { provider, operation, limitation } of limitations) {
-    const key = JSON.stringify([
-      provider.id,
-      provider.name,
-      provider.version,
-      limitation,
-    ]);
+    const key = sourceLimitationGroupKey({ provider, limitation });
     const group = groups.get(key) ?? {
       provider,
       limitation,
diff --git a/src/application/WorkflowEvidence.ts b/src/application/WorkflowEvidence.ts
index 81d4d928b5..9a8d6528a7 100644
--- a/src/application/WorkflowEvidence.ts
+++ b/src/application/WorkflowEvidence.ts
@@ -26,6 +26,7 @@ import { UnknownRegistryError } from "../domain/unknownRegistryError.js";
 import { workflowUnknownInput } from "./investigation/WorkflowUnknown.js";
 import {
   renderSourceLimitations,
+  sourceLimitationGroupKey,
   sourceLimitationKey,
   type SourceLimitation,
 } from "./SourceLimitations.js";
@@ -110,12 +111,7 @@ export const executeComposedWorkflow = async (
               omittedObservations += 1;
               continue;
             }
-            const group = JSON.stringify([
-              fact.provider.id,
-              fact.provider.name,
-              fact.provider.version,
-              limitation,
-            ]);
+            const group = sourceLimitationGroupKey(fact);
             if (!perItemGroups.has(group)) {
               if (
                 perItemGroups.size >= budget.maxDistinct ||