From d0918effa91ff023d14cb4566682596a4eedddd0 Mon Sep 17 00:00:00 2001
From: Nas Kavian <nas@inflowpay.ai>
Date: Mon, 31 Aug 2026 15:27:38 -0700
Subject: [PATCH] fix(core): validate Problem Details type

---
 .../org/offeringprotocol/odp/core/OdpJson.java     |  8 +++++++-
 .../org/offeringprotocol/odp/core/OdpJsonTest.java | 14 ++++++++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/odp-core/src/main/java/org/offeringprotocol/odp/core/OdpJson.java b/odp-core/src/main/java/org/offeringprotocol/odp/core/OdpJson.java
index 7a467fd..f576367 100644
--- a/odp-core/src/main/java/org/offeringprotocol/odp/core/OdpJson.java
+++ b/odp-core/src/main/java/org/offeringprotocol/odp/core/OdpJson.java
@@ -403,7 +403,13 @@ public static Offering parseOffering(String json) {
     }
 
     public static ProblemDetails parseProblemDetails(String json) {
-        return parse(json, "problem-details.schema.json", "Problem Details", ProblemDetails.class);
+        ProblemDetails problem = parse(json, "problem-details.schema.json", "Problem Details", ProblemDetails.class);
+        String expectedType = "https://offeringprotocol.org/problems/"
+                + problem.code().toLowerCase(Locale.ROOT).replace('_', '-');
+        if (!expectedType.equals(problem.type())) {
+            throw semanticError("Problem Details", "type must correspond to the problem code", "/type");
+        }
+        return problem;
     }
 
     public static SearchRequests.Collections parseCollectionSearchRequest(String json) {
diff --git a/odp-json-jackson3/src/test/java/org/offeringprotocol/odp/core/OdpJsonTest.java b/odp-json-jackson3/src/test/java/org/offeringprotocol/odp/core/OdpJsonTest.java
index 513428a..49fbfad 100644
--- a/odp-json-jackson3/src/test/java/org/offeringprotocol/odp/core/OdpJsonTest.java
+++ b/odp-json-jackson3/src/test/java/org/offeringprotocol/odp/core/OdpJsonTest.java
@@ -121,6 +121,20 @@ void rejectsInvalidServiceDocuments() {
         assertTrue(!exception.issues().isEmpty());
     }
 
+    @Test
+    void rejectsProblemTypesThatDoNotCorrespondToTheCode() {
+        String problem = """
+                {
+                  "code":"NOT_FOUND",
+                  "status":404,
+                  "title":"Not found",
+                  "type":"https://offeringprotocol.org/problems/validation-failed"
+                }
+                """;
+
+        assertThrows(OdpValidationException.class, () -> OdpJson.parseProblemDetails(problem));
+    }
+
     @Test
     void enforcesServiceDocumentSemanticConstraints() {
         String duplicateLocalization =