ue4ss-bridge 1.2.0

Renamed from ue-bridge to ue4ss-bridge. The old name collided with an unrelated Unreal Editor tool.

Protocol 3. Both halves must be updated together: the UEBridge mod (zip below) and the ue4ss-bridge Python package (pip install -U ue4ss-bridge or uvx ue4ss-bridge). A server and mod on different protocols refuse each other, with a message saying which side is older.

Rename

• PyPI package ue4ss-bridge, module ue4ss_bridge, command ue4ss-bridge. ue-bridge stays installed as a second command, so MCP client configs written against the old name keep launching.
• pip install -U ue-bridge keeps working: that package is now a stub that installs ue4ss-bridge.
• UE4SS_BRIDGE_GAME_DIR and UE4SS_BRIDGE_DATA_DIR, falling back to the old UE_BRIDGE_* names.
• Nothing in the game changes: the mod folder is still ue4ss\Mods\UEBridge\, and settings.lua, its keys and the request/response layout are unchanged. The archive is now named ue4ss-bridge-<version>.zip.

New

• Event streams: watch_property samples properties on a timer and records changes (default 250 ms, minimum 100). A watch holds its object between samples, survives a map change or save reload with lost / resumed rows, and ends only on stop_stream. Read-only.
• hook_function records every call of a UFunction with its arguments and caller. Refused with allow_writes = false. Read hook output through poll_events; do not call a hooked function from eval in the same session (access violation seen).
• poll_events, list_streams, stop_stream (batch ops events, streams, unwatch; CLI subcommands of the same names). One shared 2000-event buffer with sequence numbers and a dropped count.
• targeted_actor (batch op target): a line trace from the camera, or from an actor's forward vector with ref, returning the hit actor, component, distance, impact point and materials. Read-only.
• list_subclasses (batch op subclasses): every loaded class derived from a base, Blueprint classes included. About 1.5 s on a large game.

Fixed

• UEHelpers is available in eval; it previously failed with attempt to index a nil value.

UEBridge 1.1.0

Protocol 2. Both halves must be updated together: the UEBridge mod (zip below) and the ue-bridge Python package (pip install -U ue-bridge or uvx ue-bridge). A 1.0.0 server refuses a 1.1.0 mod and vice versa, with a message saying which side is older.

New

• Snapshot and diff: snapshot_object, diff_object, list_snapshots, forget_snapshot (batch ops snapshot, diff, snapshots, forget; CLI subcommands of the same names). A diff reports changed, added and removed values by dotted property path; an unchanged object diffs empty. Read-only.
• reload_mod (batch op reload, CLI reload): re-read settings.lua and re-run the mod in place. Read-only, so it works with allow_eval = false.
• CLI --super on props and snapshot includes inherited properties.

Changed

• poll_ms default 50 (was 250). Round trip median 57 ms on Lantern, 62 ms on Dawnwalker.
• scripts\settings.lua wins over a root settings.lua. An in-place upgrade from 1.0.0 leaves the root copy behind; the mod logs it as ignored. Delete it.
• inspect_object, list_functions, find_objects and list_types results over 200 entries stay JSON lists.
• bridge_status reports the game running now, not the previous one, after a game switch.
• allow_writes = false forcing allow_eval off is logged, and the eval refusal names the cause.

Tested on The Lantern of the Laughless Saint (UE 5.8) and The Blood of Dawnwalker (UE 5.5.4).

UEBridge 1.0.0

First release.

UEBridge-1.0.0.zip is the UE4SS Lua mod. Extract into the game's install folder; it lands in ue4ss\Mods\UEBridge with an enabled.txt, no mods.txt edit. Settings in scripts\settings.lua (enabled, poll_ms, allow_eval, allow_writes, bridge_dir).

The server and CLI (ue-bridge) is the Python package in this repository: MCP over stdio or --http, finds the running game by itself.

Verified on The Lantern of the Laughless Saint (UE 5.8) and The Blood of Dawnwalker (UE 5.5.4).