unity-semantic-bridgeCAUTION
Unity MCP bridge designed for Human-Agent Coworking.
Overview
From the repository's own README, as read at the audited commit. Badges and raw HTML are left out.
A Unity MCP Bridge built for agents working alongside you in a live Editor session — not just querying a static project. Token-efficient tools give your agent visibility into what changed in the scene while you were both working in it.
Note: Unity Semantic Bridge is optimized for projects that use uGUI and URP (Universal Render Pipeline).If your project uses UI Toolkit, HDRP or BiRP use the official Unity CLI instead
Features
- Optimized scene heirarchy query and gameobject inspection tools with workflow hints for agents - more token efficient than official Unity CLI tool
- In Editor connection status and auto reconnect through domain reloads.
- Not tied to Unity Licensing - Runs 100% local. No need to reauthenticate when token expires
- Dedicated tools for agent to see human actions and changes
- Dedicated tools for working with Scriptable objects (error prone if agent uses bash to work SOs directly)
- Dedicated tools for uGUI. Makes uGUI accessible for agents to create a hierarchy, set layout properties, assign references, and inspect the result
- Bounded batch inspection and property edits with dry runs, expected-value checks, stale-reference protection, and grouped Undo
- Read-only prefab comparisons with component filtering and structured numeric values that preserve imported precision
- In Editor MCP log so you can see what tools are called
- Dedicated Lighting tools for URP projects
Prerequisites
Installation
Install both the Unity package and the Python MCP server:
- In U
e1ccc9b71e89OBSERVED · 2026-10-10Connect
Built from this server's own package name, version and transport as found in its source — not copied from anyone's documentation, so it cannot drift against a page we do not control.
claude mcp add com.gamenami.unity-semantic-bridge -- npx -y [email protected]
{
"mcpServers": {
"com.gamenami.unity-semantic-bridge": {
"command": "npx",
"args": [
"-y",
"[email protected]"
]
}
}
}Exposed tools (33)
20 read · 9 write · 4 destructive. Blast radius: 4 tools can delete or overwrite — an agent that can be talked into calling a tool can be talked into calling this one.
| Tool | Risk | Description |
|---|---|---|
add_component | write | |
author_ui | write | Create/revise ordinary uGUI in one Edit Mode transaction on Unity |
clear_console_logs | destructive | Clears old Unity Editor console logs. |
create_gameobject | write | |
create_scriptable_object | write | |
delete_asset | destructive | Deletes an asset via AssetDatabase.DeleteAsset (supports Undo). |
delete_gameobject | destructive | |
find_asset_references | read | Finds all assets or scenes that reference a specific asset path. |
get_asset_catalog_status | read | |
get_compilation_status | read | |
get_component_code | read | |
get_component_inspector_values | read | |
get_console_logs | read | Returns the most recent errors and warnings from the Unity Console. |
get_gameobject_tree | read | |
get_lights_affecting_object | read | |
get_physics_layers | read | |
get_project_settings | read | |
get_project_tree | read | Returns the folder structure starting from the given path. |
get_recent_unity_events | read | Returns Unity Editor events (hierarchy/selection/play-mode/console/objectChanged changes) |
get_screenshot | read | |
get_urp_pipeline_settings | read | Returns the URP render pipeline asset |
inspect_gameobject | read | |
inspect_ui | read | Inspect calculated uGUI layout, screen bounds, visibility estimates, interaction, |
notify_unity | read | Sends a message to the Unity Editor chat window. |
raycast_ui | read | Query actual raycasters, returning each hit |
refresh_assets | read | Queue AssetDatabase.Refresh on Unity |
remove_component | destructive | Remove a component by instance_id |
save_ui_context | write | Explicitly save the entire containing scene or current prefab contents, including |
set_editor_throttling | write | Explicitly change Unity |
set_parent | write | |
set_play_mode | write | Enters or exits Play Mode in the Unity Editor. |
undo_ui_batch | read | Undo the latest UI batch only if no intervening Undo activity occurred. |
update_scriptable_object | write |
Trust audit
CAUTIONgrade B · trust 89/100 Install with care. The audit found things worth knowing before you trust its output.
| Layer | What it checks | Result |
|---|---|---|
| L0 | Provenance & inventory | PASS |
| L1 | Static analysis of the code | WARN |
| L2 | Instruction surface (what it tells the agent) | PASS |
| L3 | Class-specific surface | WARN |
| L4 | Behavioural (sandbox) | SKIPPED |
What the source does
- Filesystem
- declared (1 observation(s))
- Network
- declared (4 observation(s))
- Shell
- none-observed
- Dependencies
- pinned
- Secrets in source
- none-found
Findings (8)
/// <c>SendNotification("unity/hierarchyChanged", new JObject{...})</c> -> POST http://127.0.0.1:1074/rpc (via <see cref="SendRequestAsync"/>, acked)private static readonly string Prefix = $"http://127.0.0.1:{Port}/";private static readonly string PythonRpcUrl = $"http://127.0.0.1:{PythonEventPort}/rpc";EditorGUILayout.HelpBox($"HTTP bridge active at http://127.0.0.1:{EditorBridge.ListeningPort}/rpc — ready to receive JSON-RPC commands.", MessageType.Info);clear_console_logs, delete_asset, delete_gameobject, remove_component
`http://127.0.0.1:1073/rpc`. Unity sends events to Python at
return Image(data=base64.b64decode(result), format="jpeg")
images/usb-editor-mode.png
Gates applied: no_behavioural_pass.
e1ccc9b71e89full audit observations/trust-audit/mcp-server/programalyst__unity-semantic-bridge.json · Report an issue / request a re-scanAudit history
Every audit this server has had. A grade with a past is a grade somebody is still checking.
| Date | Source | Verdict | Grade | Score | Change |
|---|---|---|---|---|---|
| 2026-10-10 | e1ccc9b71e89 | CAUTION | B | 89 | first audit |
Questions
What is the unity-semantic-bridge MCP server?
Unity MCP bridge designed for Human-Agent Coworking.
What tools does unity-semantic-bridge expose?
33 in total: 20 read-only, 9 that write, and 4 that can delete or overwrite (clear_console_logs, delete_asset, delete_gameobject, remove_component). Every one is listed on this page with its risk.
Is unity-semantic-bridge safe to connect to an agent?
With care. The audit graded it B (89/100) and found 8 things worth knowing before you trust this server, listed below with the exact line each was found on. Separately from the audit: 4 of its tools can destroy data, so scope the token you give it to what you actually need.
What credentials does unity-semantic-bridge need?
No credential environment variables were found in its source, so it appears to need none.
How current is this page?
The grade is for one exact copy of the source (e1ccc9b71e89), read on 2026-10-10. The repository is watched and re-audited when it changes.