diff --git a/README.md b/README.md
index 43257d9..f0b1b34 100644
--- a/README.md
+++ b/README.md
@@ -125,7 +125,8 @@ By default it listens on http://127.0.0.1:3030.
             "POST /torrents/{index}/delete": "Forget about the torrent, remove the files",
             "POST /torrents/{index}/forget": "Forget about the torrent, keep the files",
             "POST /torrents/{index}/pause": "Pause torrent",
-            "POST /torrents/{index}/start": "Resume torrent"
+            "POST /torrents/{index}/start": "Resume torrent",
+            "POST /torrents/{index}/update_only_files": "Change the selection of files to download. You need to POST json of the following form {"only_files": [0, 1, 2]}"
         },
         "server": "rqbit"
     }
diff --git a/crates/librqbit/src/chunk_tracker.rs b/crates/librqbit/src/chunk_tracker.rs
index 8f03dd9..21590b0 100644
--- a/crates/librqbit/src/chunk_tracker.rs
+++ b/crates/librqbit/src/chunk_tracker.rs
@@ -493,10 +493,10 @@ mod tests {
 
         let bf_len = l.piece_bitfield_bytes();
         let initial_have = BF::from_boxed_slice(vec![0u8; bf_len].into_boxed_slice());
-        let initial_needed = BF::from_boxed_slice(vec![u8::MAX; bf_len].into_boxed_slice());
+        let initial_selected = BF::from_boxed_slice(vec![u8::MAX; bf_len].into_boxed_slice());
 
         // Initially, we need all files and all pieces.
-        let mut ct = ChunkTracker::new(initial_needed.clone(), initial_have.clone(), l).unwrap();
+        let mut ct = ChunkTracker::new(initial_have.clone(), initial_selected.clone(), l).unwrap();
 
         // Select all file, no changes.
         assert_eq!(
@@ -509,7 +509,7 @@ mod tests {
             }
         );
         assert_eq!(ct.have, initial_have);
-        assert_eq!(ct.queue_pieces, initial_needed);
+        assert_eq!(ct.queue_pieces, initial_selected);
 
         // Select only the first file.
         println!("Select only the first file.");
diff --git a/crates/librqbit/src/http_api.rs b/crates/librqbit/src/http_api.rs
index 44fc9d9..ccb0a5e 100644
--- a/crates/librqbit/src/http_api.rs
+++ b/crates/librqbit/src/http_api.rs
@@ -64,6 +64,7 @@ impl HttpApi {
                     "POST /torrents/{index}/start": "Resume torrent",
                     "POST /torrents/{index}/forget": "Forget about the torrent, keep the files",
                     "POST /torrents/{index}/delete": "Forget about the torrent, remove the files",
+                    "POST /torrents/{index}/update_only_files": "Change the selection of files to download. You need to POST json of the following form {\"only_files\": [0, 1, 2]}",
                     "POST /torrents": "Add a torrent here. magnet: or http:// or a local file.",
                     "POST /rust_log": "Set RUST_LOG to this post launch (for debugging)",
                     "GET /web/": "Web UI",