diff --git a/agentscope-extensions/agentscope-extensions-jdbc/src/main/java/io/agentscope/extensions/jdbc/state/JdbcAgentStateStore.java b/agentscope-extensions/agentscope-extensions-jdbc/src/main/java/io/agentscope/extensions/jdbc/state/JdbcAgentStateStore.java
index daa94a4e37..a5b0c808bb 100644
--- a/agentscope-extensions/agentscope-extensions-jdbc/src/main/java/io/agentscope/extensions/jdbc/state/JdbcAgentStateStore.java
+++ b/agentscope-extensions/agentscope-extensions-jdbc/src/main/java/io/agentscope/extensions/jdbc/state/JdbcAgentStateStore.java
@@ -233,7 +233,7 @@ public long saveIfVersion(
             String userId, String sessionId, String key, State value, long expectedVersion) {
         if (expectedVersion == UNVERSIONED) {
             save(userId, sessionId, key, value);
-            return getVersioned(userId, sessionId, key, State.class).version();
+            return readVersionOnly(userId, sessionId, key);
         }
         String slotId = slotId(userId, sessionId);
         validateSlotId(slotId);
@@ -276,6 +276,26 @@ public long saveIfVersion(
         }
     }
 
+    private long readVersionOnly(String userId, String sessionId, String key) {
+        String slotId = slotId(userId, sessionId);
+        validateSlotId(slotId);
+        validateStateKey(key);
+
+        BoundSql boundSql = dialect.sessionStateSelectVersioned(slotId, key, SINGLE_STATE_INDEX);
+        try (Connection conn = dataSource.getConnection();
+                PreparedStatement stmt = conn.prepareStatement(boundSql.sql())) {
+            bindParams(stmt, boundSql.params());
+            try (ResultSet rs = stmt.executeQuery()) {
+                if (!rs.next()) {
+                    return 0L;
+                }
+                return rs.getLong("version");
+            }
+        } catch (Exception e) {
+            throw new RuntimeException("Failed to read version for state: " + key, e);
+        }
+    }
+
     @Override
     public <T extends State> Optional<T> get(
             String userId, String sessionId, String key, Class<T> type) {
diff --git a/agentscope-extensions/agentscope-extensions-mysql/src/main/java/io/agentscope/extensions/mysql/state/MysqlAgentStateStore.java b/agentscope-extensions/agentscope-extensions-mysql/src/main/java/io/agentscope/extensions/mysql/state/MysqlAgentStateStore.java
index 6580e077fe..25a0a8f3c8 100644
--- a/agentscope-extensions/agentscope-extensions-mysql/src/main/java/io/agentscope/extensions/mysql/state/MysqlAgentStateStore.java
+++ b/agentscope-extensions/agentscope-extensions-mysql/src/main/java/io/agentscope/extensions/mysql/state/MysqlAgentStateStore.java
@@ -425,7 +425,7 @@ public long saveIfVersion(
             String userId, String sessionId, String key, State value, long expectedVersion) {
         if (expectedVersion == UNVERSIONED) {
             save(userId, sessionId, key, value);
-            return getVersioned(userId, sessionId, key, State.class).version();
+            return readVersionOnly(userId, sessionId, key);
         }
 
         String slotId = slotId(userId, sessionId);
@@ -449,6 +449,29 @@ public long saveIfVersion(
         }
     }
 
+    private long readVersionOnly(String userId, String sessionId, String key) {
+        String slotId = slotId(userId, sessionId);
+        validateSessionId(slotId);
+        validateStateKey(key);
+
+        String sql = "SELECT version FROM " + getFullTableName()
+                + " WHERE session_id = ? AND state_key = ? AND item_index = 0";
+
+        try (Connection conn = dataSource.getConnection();
+             PreparedStatement stmt = conn.prepareStatement(sql)) {
+            stmt.setString(1, slotId);
+            stmt.setString(2, key);
+            try (ResultSet rs = stmt.executeQuery()) {
+                if (!rs.next()) {
+                    return 0L;
+                }
+                return rs.getLong("version");
+            }
+        } catch (Exception e) {
+            throw new RuntimeException("Failed to read version for state: " + key, e);
+        }
+    }
+
     private long insertIfAbsent(Connection conn, String slotId, String key, State value)
             throws Exception {
         String insertSql =
diff --git a/agentscope-extensions/agentscope-extensions-postgresql/src/main/java/io/agentscope/extensions/postgresql/state/PostgresAgentStateStore.java b/agentscope-extensions/agentscope-extensions-postgresql/src/main/java/io/agentscope/extensions/postgresql/state/PostgresAgentStateStore.java
index 24323f130b..cf32c9c397 100644
--- a/agentscope-extensions/agentscope-extensions-postgresql/src/main/java/io/agentscope/extensions/postgresql/state/PostgresAgentStateStore.java
+++ b/agentscope-extensions/agentscope-extensions-postgresql/src/main/java/io/agentscope/extensions/postgresql/state/PostgresAgentStateStore.java
@@ -330,7 +330,7 @@ public long saveIfVersion(
             String userId, String sessionId, String key, State value, long expectedVersion) {
         if (expectedVersion == UNVERSIONED) {
             save(userId, sessionId, key, value);
-            return getVersioned(userId, sessionId, key, State.class).version();
+            return readVersionOnly(userId, sessionId, key);
         }
 
         String slotId = slotId(userId, sessionId);
@@ -354,6 +354,29 @@ public long saveIfVersion(
         }
     }
 
+    private long readVersionOnly(String userId, String sessionId, String key) {
+        String slotId = slotId(userId, sessionId);
+        validateSessionId(slotId);
+        validateStateKey(key);
+
+        String sql = "SELECT version FROM " + getFullTableName()
+                + " WHERE session_id = ? AND state_key = ? AND item_index = 0";
+
+        try (Connection conn = dataSource.getConnection();
+             PreparedStatement stmt = conn.prepareStatement(sql)) {
+            stmt.setString(1, slotId);
+            stmt.setString(2, key);
+            try (ResultSet rs = stmt.executeQuery()) {
+                if (!rs.next()) {
+                    return 0L;
+                }
+                return rs.getLong("version");
+            }
+        } catch (Exception e) {
+            throw new RuntimeException("Failed to read version for state: " + key, e);
+        }
+    }
+
     private long insertIfAbsent(Connection conn, String slotId, String key, State value)
             throws Exception {
         String insertSql =
diff --git a/agentscope-extensions/agentscope-extensions-redis/src/main/java/io/agentscope/extensions/redis/state/RedisAgentStateStore.java b/agentscope-extensions/agentscope-extensions-redis/src/main/java/io/agentscope/extensions/redis/state/RedisAgentStateStore.java
index 7679fd8b5e..a7c43303b8 100644
--- a/agentscope-extensions/agentscope-extensions-redis/src/main/java/io/agentscope/extensions/redis/state/RedisAgentStateStore.java
+++ b/agentscope-extensions/agentscope-extensions-redis/src/main/java/io/agentscope/extensions/redis/state/RedisAgentStateStore.java
@@ -270,8 +270,7 @@ public long saveIfVersion(
             String userId, String sessionId, String key, State value, long expectedVersion) {
         if (expectedVersion == UNVERSIONED) {
             save(userId, sessionId, key, value);
-            VersionedState<State> after = getVersioned(userId, sessionId, key, State.class);
-            return after.version();
+            return readVersionOnly(userId, sessionId, key);
         }
         String slotId = slotId(userId, sessionId);
         String redisKey = getStateKey(slotId, key);
@@ -290,6 +289,25 @@ public long saveIfVersion(
         }
     }
 
+    /**
+     * Read only the version number without deserializing the payload.
+     * This avoids Jackson's inability to deserialize the State marker interface.
+     */
+    private long readVersionOnly(String userId, String sessionId, String key) {
+        String slotId = slotId(userId, sessionId);
+        String redisKey = getStateKey(slotId, key);
+        String versionKey = RedisStateVersionSupport.versionKey(redisKey);
+        try {
+            String json = client.get(redisKey);
+            if (json == null) {
+                return 0L;
+            }
+            return RedisStateVersionSupport.parseVersion(json, client.get(versionKey));
+        } catch (Exception e) {
+            throw new RuntimeException("Failed to read version for state: " + key, e);
+        }
+    }
+
     @Override
     public void save(String userId, String sessionId, String key, List<? extends State> values) {
         String slotId = slotId(userId, sessionId);
diff --git a/agentscope-extensions/agentscope-extensions-redis/src/main/java/io/agentscope/extensions/redis/state/jedis/JedisAgentStateStore.java b/agentscope-extensions/agentscope-extensions-redis/src/main/java/io/agentscope/extensions/redis/state/jedis/JedisAgentStateStore.java
index 0513656db5..458f326124 100644
--- a/agentscope-extensions/agentscope-extensions-redis/src/main/java/io/agentscope/extensions/redis/state/jedis/JedisAgentStateStore.java
+++ b/agentscope-extensions/agentscope-extensions-redis/src/main/java/io/agentscope/extensions/redis/state/jedis/JedisAgentStateStore.java
@@ -119,11 +119,26 @@ public long saveIfVersion(
             String userId, String sessionId, String key, State value, long expectedVersion) {
         if (expectedVersion == UNVERSIONED) {
             save(userId, sessionId, key, value);
-            return getVersioned(userId, sessionId, key, State.class).version();
+            return readVersionOnly(userId, sessionId, key);
         }
         return evalSave(userId, sessionId, key, value, Long.toString(expectedVersion));
     }
 
+    private long readVersionOnly(String userId, String sessionId, String key) {
+        String slotId = slotId(userId, sessionId);
+        String redisKey = getStateKey(slotId, key);
+        String versionKey = RedisStateVersionSupport.versionKey(redisKey);
+        try (Jedis jedis = jedisPool.getResource()) {
+            String json = jedis.get(redisKey);
+            if (json == null) {
+                return 0L;
+            }
+            return RedisStateVersionSupport.parseVersion(json, jedis.get(versionKey));
+        } catch (Exception e) {
+            throw new RuntimeException("Failed to read version for state: " + key, e);
+        }
+    }
+
     private long evalSave(
             String userId, String sessionId, String key, State value, String expectedVersionArg) {
         String slotId = slotId(userId, sessionId);
diff --git a/agentscope-extensions/agentscope-extensions-redis/src/main/java/io/agentscope/extensions/redis/state/redisson/RedissonAgentStateStore.java b/agentscope-extensions/agentscope-extensions-redis/src/main/java/io/agentscope/extensions/redis/state/redisson/RedissonAgentStateStore.java
index f497da3818..b123cc75b5 100644
--- a/agentscope-extensions/agentscope-extensions-redis/src/main/java/io/agentscope/extensions/redis/state/redisson/RedissonAgentStateStore.java
+++ b/agentscope-extensions/agentscope-extensions-redis/src/main/java/io/agentscope/extensions/redis/state/redisson/RedissonAgentStateStore.java
@@ -125,11 +125,28 @@ public long saveIfVersion(
             String userId, String sessionId, String key, State value, long expectedVersion) {
         if (expectedVersion == UNVERSIONED) {
             save(userId, sessionId, key, value);
-            return getVersioned(userId, sessionId, key, State.class).version();
+            return readVersionOnly(userId, sessionId, key);
         }
         return evalSave(userId, sessionId, key, value, Long.toString(expectedVersion));
     }
 
+    private long readVersionOnly(String userId, String sessionId, String key) {
+        String slotId = slotId(userId, sessionId);
+        String redisKey = getStateKey(slotId, key);
+        String versionKey = RedisStateVersionSupport.versionKey(redisKey);
+        try {
+            RBucket<String> bucket = redissonClient.getBucket(redisKey, StringCodec.INSTANCE);
+            String json = bucket.get();
+            if (json == null) {
+                return 0L;
+            }
+            RBucket<String> versionBucket = redissonClient.getBucket(versionKey, StringCodec.INSTANCE);
+            return RedisStateVersionSupport.parseVersion(json, versionBucket.get());
+        } catch (Exception e) {
+            throw new RuntimeException("Failed to read version for state: " + key, e);
+        }
+    }
+
     private long evalSave(
             String userId, String sessionId, String key, State value, String expectedVersionArg) {
         String slotId = slotId(userId, sessionId);