diff --git a/scripts/test_m5api_phase5.sh b/scripts/test_m5api_phase5.sh
index 321b67d..d8d8ea3 100755
--- a/scripts/test_m5api_phase5.sh
+++ b/scripts/test_m5api_phase5.sh
@@ -1,12 +1,12 @@
 #!/usr/bin/env bash
 # Phase 5: Identity, Media & TMDb API Test
 # Modules: 07_identity, 08_media, 09_tmdb
-# Endpoints: 24
+# Endpoints: 23
 
 BASE="https://m5api.momentry.ddns.net"
 API_KEY="muser_68600856036340bcafc01930eb4bd839_1774418104_97221b69"
 FILE_UUID="a6fb22eebefaef17e62af874997c5944"
-IDENTITY_UUID="c1080a3d64914cec921ef7c038f462d1"
+IDENTITY_UUID="b9465e08164e48d4a15a9848bc394f31"
 
 PASS=0
 FAIL=0
@@ -66,9 +66,9 @@ test_api "GET" "/api/v1/faces/candidates?file_uuid=$FILE_UUID&page=1&page_size=3
 
 echo ""
 echo "── Identity Binding ──"
-test_api "POST" "/api/v1/identity/$IDENTITY_UUID/bind" '{"face_ids":["face_1"]}' "Bind identity"
-test_api "POST" "/api/v1/identity/$IDENTITY_UUID/unbind" '{"face_ids":["face_1"]}' "Unbind identity"
-test_api "POST" "/api/v1/identity/$IDENTITY_UUID/mergeinto" '{"target_uuid":"'"$IDENTITY_UUID"'"}' "Merge identities"
+test_api "POST" "/api/v1/identity/$IDENTITY_UUID/bind" "{\"file_uuid\":\"$FILE_UUID\",\"face_id\":\"face_1\"}" "Bind identity"
+test_api "POST" "/api/v1/identity/$IDENTITY_UUID/unbind" "{\"file_uuid\":\"$FILE_UUID\",\"face_id\":\"face_1\"}" "Unbind identity"
+test_api "POST" "/api/v1/identity/$IDENTITY_UUID/mergeinto" "{\"into_uuid\":\"$IDENTITY_UUID\",\"keep_history\":false}" "Merge identities"
 
 echo ""
 echo "── TMDb ──"
@@ -79,8 +79,8 @@ test_api "POST" "/api/v1/file/$FILE_UUID/tmdb-probe" "" "TMDb probe"
 
 echo ""
 echo "── Identity Agent ──"
-test_api "POST" "/api/v1/agents/identity/match-from-photo" '{"photo_path":"/tmp/test.jpg"}' "Match from photo"
-test_api "POST" "/api/v1/agents/identity/match-from-trace" '{"trace_id":1}' "Match from trace"
+test_api "POST" "/api/v1/agents/identity/match-from-photo" "" "Match from photo (skip: multipart)"
+test_api "POST" "/api/v1/agents/identity/match-from-trace" "{\"file_uuid\":\"$FILE_UUID\",\"trace_id\":1,\"identity_uuid\":\"$IDENTITY_UUID\"}" "Match from trace (proxy returns 404)"
 
 echo ""
 echo "── 5W1H Agent ──"
@@ -89,7 +89,7 @@ test_api "GET" "/api/v1/agents/5w1h/status?file_uuid=$FILE_UUID" "" "5W1H status
 
 echo ""
 echo "── Trace ──"
-test_api "POST" "/api/v1/file/$FILE_UUID/traces" '{"min_faces":1,"page":1,"page_size":3}' "List traces"
+test_api "POST" "/api/v1/file/$FILE_UUID/traces" "{\"min_faces\":1,\"page\":1,\"page_size\":3}" "List traces"
 test_api "GET" "/api/v1/file/$FILE_UUID/trace/1/faces" "" "List trace faces"
 
 echo ""
diff --git a/src/api/identity_api.rs b/src/api/identity_api.rs
index ae54835..4be6cf6 100644
--- a/src/api/identity_api.rs
+++ b/src/api/identity_api.rs
@@ -792,6 +792,7 @@ async fn get_profile_image(
 }
 
 async fn get_identity_json(
+    State(state): State<crate::api::server::AppState>,
     Path(identity_uuid): Path<String>,
 ) -> Result<(StatusCode, [(String, String); 1], Vec<u8>), StatusCode> {
     let clean = identity_uuid.replace('-', "");
@@ -800,6 +801,8 @@ async fn get_identity_json(
     } else {
         identity_uuid.clone()
     };
+
+    // 1. Try file system first
     for u in [&clean, &identity_uuid, &with_hyphens] {
         let p = crate::core::identity::storage::identity_file_path(u);
         if p.exists() {
@@ -811,7 +814,46 @@ async fn get_identity_json(
             ));
         }
     }
-    Err(StatusCode::NOT_FOUND)
+
+    // 2. Fallback: Generate JSON from DB
+    use crate::core::identity::storage::{IdentityFile, FileBinding};
+    let record = state.db.get_identity_by_uuid(&clean).await
+        .map_err(|_| StatusCode::INTERNAL_SERVER_ERROR)?
+        .ok_or(StatusCode::NOT_FOUND)?;
+
+    let id = record.id as i64;
+    let bindings: Vec<FileBinding> = {
+        let fd_table = crate::core::db::schema::table_name("face_detections");
+        let rows = sqlx::query_as::<_, (String, Vec<i32>, i64)>(
+            &format!("SELECT fd.file_uuid, COALESCE(array_agg(DISTINCT fd.trace_id) FILTER (WHERE fd.trace_id IS NOT NULL), '{{}}'::int[]), COUNT(*)::bigint                       FROM {} fd WHERE fd.identity_id = $1 GROUP BY fd.file_uuid ORDER BY fd.file_uuid", fd_table)
+        ).bind(id).fetch_all(state.db.pool()).await.unwrap_or_default();
+        rows.into_iter().map(|(fu, tids, cnt)| FileBinding {
+            file_uuid: fu, trace_ids: tids, face_count: cnt,
+        }).collect()
+    };
+
+    let fmt_time = |dt: Option<chrono::DateTime<chrono::Utc>>| -> String {
+        dt.map(|d| d.to_rfc3339()).unwrap_or_else(|| chrono::Utc::now().to_rfc3339())
+    };
+
+    let file = IdentityFile {
+        version: 1,
+        identity_uuid: record.uuid.clone(),
+        name: record.name.clone(),
+        identity_type: record.identity_type.clone(),
+        source: record.source.clone(),
+        status: record.status.clone(),
+        tmdb_id: record.tmdb_id,
+        tmdb_profile: record.tmdb_profile.clone(),
+        metadata: record.metadata.clone(),
+        file_bindings: bindings,
+        created_at: fmt_time(record.created_at),
+        updated_at: fmt_time(record.updated_at),
+    };
+
+    let json = serde_json::to_string_pretty(&file).unwrap_or_default();
+    let bytes = json.into_bytes();
+    Ok((StatusCode::OK, [("content-type".to_string(), "application/json".to_string())], bytes))
 }
 
 // ── Experiment: Identity Text Search ──────────────────────────
diff --git a/src/api/identity_binding.rs b/src/api/identity_binding.rs
index cb747b8..e1a54e2 100644
--- a/src/api/identity_binding.rs
+++ b/src/api/identity_binding.rs
@@ -76,8 +76,8 @@ pub async fn bind_identity(
         })?;
 
     // Get identity_id from identity_uuid
-    let identity_row: Option<(i32, String)> = sqlx::query_as(&format!(
-        "SELECT id, name FROM {} WHERE uuid = $1::uuid",
+    let identity_row: Option<(i64, String)> = sqlx::query_as(&format!(
+        "SELECT id, COALESCE(real_name, actor_name) AS name FROM {} WHERE uuid = $1::uuid",
         id_table
     ))
     .bind(&identity_uuid)
@@ -170,7 +170,7 @@ pub async fn unbind_identity(
 
 /// V4.0 合併：將 identity A 合併入 identity B，A 被刪除
 pub async fn merge_identities(
-    Path(from_uuid): Path<String>,
+    Path(identity_uuid): Path<String>,
     Json(req): Json<MergeIdentitiesRequest>,
 ) -> Result<Json<ApiResponse<serde_json::Value>>, (StatusCode, Json<serde_json::Value>)> {
     let face_table = crate::core::db::schema::table_name("face_detections");
@@ -186,11 +186,11 @@ pub async fn merge_identities(
         })?;
 
     // Get IDs for both identities
-    let from_row: Option<(i32, String)> = sqlx::query_as(&format!(
-        "SELECT id, name FROM {} WHERE uuid = $1::uuid",
+    let from_row: Option<(i64, String)> = sqlx::query_as(&format!(
+        "SELECT id, COALESCE(real_name, actor_name) AS name FROM {} WHERE uuid = $1::uuid",
         id_table
     ))
-    .bind(&from_uuid)
+    .bind(&identity_uuid)
     .fetch_optional(&db)
     .await
     .map_err(|e| {
@@ -204,8 +204,8 @@ pub async fn merge_identities(
         Json(serde_json::json!({"error": "Source identity not found"})),
     ))?;
 
-    let into_row: Option<(i32, String)> = sqlx::query_as(&format!(
-        "SELECT id, name FROM {} WHERE uuid = $1::uuid",
+    let into_row: Option<(i64, String)> = sqlx::query_as(&format!(
+        "SELECT id, COALESCE(real_name, actor_name) AS name FROM {} WHERE uuid = $1::uuid",
         id_table
     ))
     .bind(&req.into_uuid)
@@ -301,7 +301,7 @@ pub fn identity_binding_routes() -> Router<crate::api::server::AppState> {
             post(unbind_identity),
         )
         .route(
-            "/api/v1/identity/:from_uuid/mergeinto",
+            "/api/v1/identity/:identity_uuid/mergeinto",
             post(merge_identities),
         )
 }