diff --git a/codex/rest/api.nim b/codex/rest/api.nim
index 6c3fce33..3d2c680e 100644
--- a/codex/rest/api.nim
+++ b/codex/rest/api.nim
@@ -93,6 +93,26 @@ proc formatPeerRecord(peerRecord: PeerRecord): JsonNode =
   }
   return jobj
 
+proc formatBlockExchangePeers(peers: OrderedTable[PeerId, BlockExcPeerCtx]): JsonNode =
+  let jarray = newJArray()
+  for peerId, peerContext in peers.pairs:
+    let jblocksArray = newJArray()
+    for cid, presence in peerContext.blocks:
+      jblocksArray.add(%*{
+        "cid": $presence.cid,
+        "have": $presence.have,
+        "price": $presence.price
+      })
+
+    jarray.add(%*{
+      "peerid": $peerId,
+      "hasBlocks": jblocksArray,
+      "wants": $peerContext.peerWants.len,
+      "exchanged": $peerContext.exchanged,
+    })
+
+  return jarray
+
 proc initRestApi*(node: CodexNodeRef, conf: CodexConf): RestRouter =
   var router = RestRouter.init(validate)
   router.api(
@@ -321,6 +341,16 @@ proc initRestApi*(node: CodexNodeRef, conf: CodexConf): RestRouter =
         trace "debug/peer returning peer record"
         return RestApiResponse.response($json)
 
+    router.api(
+      MethodGet,
+      "/api/codex/v1/debug/blockexchange") do () -> RestApiResponse:
+        let json = %*{
+          "peers": formatBlockExchangePeers(node.engine.peers.peers),
+          "taskQueue": $node.engine.taskQueue.len,
+          "pendingBlocks": $node.engine.pendingBlocks.blocks.len
+        }
+        return RestApiResponse.response($json)
+
   router.api(
     MethodGet,
     "/api/codex/v1/sales/slots") do () -> RestApiResponse:
diff --git a/codex/stores/repostore.nim b/codex/stores/repostore.nim
index 52e06dd4..5a78d431 100644
--- a/codex/stores/repostore.nim
+++ b/codex/stores/repostore.nim
@@ -294,10 +294,13 @@ method listBlocks*(
     await idleAsync()
     iter.finished = queryIter.finished
     if not queryIter.finished:
-      if pair =? (await queryIter.next()) and cid =? pair.key:
+      if pair =? (await queryIter.next()) and key =? pair.key:
         doAssert pair.data.len == 0
-        trace "Retrieved record from repo", cid
-        return Cid.init(cid.value).option
+        trace "Retrieved record from repo", key
+        without cid =? Cid.init(key.value):
+          error "Could not init Cid for key", key
+          raise Defect.newException("Repostore: Could not init Cid from key during listBlocks iteration.")
+        return cid.option
 
     return Cid.none