io.github.ObscuritySRL/umbriel
MCPby ObscuritySRL · v1.14.0
See and drive a whole Windows machine from Bun — apps, input, screen, OCR, registry, OS — via MCP.
MCP configuration
Command
Environment
UMBRIEL_PROFILECapability profile: 'readonly' (inspect/read only), 'safe' (read + input + window — default), or 'full' (also os + fs tools).
UMBRIEL_OSSet to '1' to allow the 'os' tools (launch_app/run_program/open_path, kill_process, manage_process, control_service, set_env, registry_get/registry_list/registry_set) AND the 'fs' tools (read_file/write_file/list_dir/stat_path/make_dir/copy_file/move_file/delete_file) regardless of profile.
UMBRIEL_ALLOWComma-separated tool names or categories to additionally allow on top of the profile.
UMBRIEL_DENYComma-separated tool names or categories to deny, overriding the profile and UMBRIEL_ALLOW.
UMBRIEL_CURSORSet to 'never' to forbid the real-cursor fallback entirely (strictly cursor-free). By default clicks/drags are cursor-free but fall back to the real hardware cursor when no cursor-free path exists.
UMBRIEL_FS_ROOTSandbox root directory that the fs-category file tools (read_file/write_file/list_dir/stat_path/make_dir/copy_file/move_file/delete_file) are confined to when fs tools are enabled; open_path's path argument is honored too.
UMBRIEL_TRACEFile path to journal every mutating tool call as JSON Lines (tool, category, masked args, ok, observation); secret-bearing args and values are redacted. Unset = no trace.
UMBRIEL_FFI_TRACEFile path to a flush-before-call diagnostic journal of every COM vcall (slot, this-pointer, arg count). Each line is written and flushed to the OS BEFORE the native call, so after an uncatchable crash the last line names the faulting call. Has per-call overhead; unset = off. For debugging native faults only.
UMBRIEL_AUDITControls the default-on stderr audit of mutating tool calls. 'off' is the explicit opt-out (reported at startup); 'verbose' also audits reads.
UMBRIEL_REDACTCredential masking (default on). 'off' opts out; a regex value overrides the built-in secret shapes masked in clipboard/env/registry reads and the trace journal.
Install in one click with Zurek
Browse here, install from the native macOS app — pick targets, fill env vars, and write configs safely.