From 495fc70bd7c5c93360306504790402188ccb20cf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?M=C3=A5ns?= <mons@peltarion.com>
Date: Mon, 17 Nov 2025 15:50:13 +0100
Subject: [PATCH] Let OAuth discovery skip to next well-known URL candidate on
 JSON parse error.

---
 crates/rmcp/src/transport/auth.rs | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/crates/rmcp/src/transport/auth.rs b/crates/rmcp/src/transport/auth.rs
index 7ebbb955..a5b3918a 100644
--- a/crates/rmcp/src/transport/auth.rs
+++ b/crates/rmcp/src/transport/auth.rs
@@ -604,12 +604,14 @@ impl AuthorizationManager {
             return Ok(None);
         }
 
-        let metadata = response
-            .json::<AuthorizationMetadata>()
-            .await
-            .map_err(|e| AuthError::MetadataError(format!("Failed to parse metadata: {}", e)))?;
-        debug!("metadata: {:?}", metadata);
-        Ok(Some(metadata))
+        let body = response.text().await?;
+        match serde_json::from_str::<AuthorizationMetadata>(&body) {
+            Ok(metadata) => Ok(Some(metadata)),
+            Err(err) => {
+                debug!("Failed to parse metadata for {}: {}", discovery_url, err);
+                Ok(None) // malformed JSON ⇒ try next candidate
+            }
+        }
     }
 
     async fn discover_oauth_server_via_resource_metadata(