Computeruse

Python Tauri React Ollama MCP

ComputerUse is a local desktop-control agent for Ollama vision models. It captures the screen, asks a selected local model for exactly one structured action, executes that small action through local mouse and keyboard tools, verifies the result with a fresh screenshot, and repeats until the task is done.

It is built for the daily computer-use workflow: observe, plan, act, verify.

Video Preview

ComputerUse demo video preview

Watch the demo: ComputerUse local AI desktop agent

Natural-language task
  -> Tauri + React desktop runner
  -> Python worker over newline-delimited JSON
  -> screenshot + perception
  -> Ollama vision planner
  -> Pydantic action validation
  -> local mouse/keyboard executor
  -> verification screenshot
  -> session state, timing events, and UI updates

Highlights

• Polished desktop task runner with model selection, screenshot preview, timeline, status, history, and debug timings.
• CLI path for development, dry runs, model listing, screenshots, and automation.
• Local Ollama integration with known vision-capable models ranked first.
• Strict one-action-at-a-time planner contract backed by Pydantic validation.
• Screenshot capture with mss, plus planner overlays and optional UI Automation element collection.
• Local mouse, keyboard, scroll, drag, wait, screenshot, done, and fail action handlers.
• Pause, resume, stop, dry-run, and max-step controls.
• Stdio MCP server for external agents that want safe observe -> execute -> verify computer-use tools.
• Local-only runtime files for the active session, screenshots, timing logs, and run history.

Execution History & Benchmarks

The current local runtime history has been read from data/computeruse.sqlite3 and logs/debug_timing.jsonl. These numbers are a real desktop-run snapshot from timing records dated 2026-07-05 UTC, not synthetic lab benchmarks.

History Snapshot

Metric	Value
SQLite sessions	5
Completed sessions	3
Cancelled sessions	1
Running session records	1
Tracked SQLite steps	58
Successful tool steps	56 / 58, 96.6%
Valid timing log records	108
Timing log models	kimi-k2.6:cloud, gemma4:31b-cloud

Most recorded actions were UI-targeted interactions: click_element was the dominant action, followed by type_text, press, done, hotkey, click_target, move, and double_click.

Timing Snapshot

Phase	Samples	Average	P50	P95	Notes
Screenshot capture	107	16.3 ms	16.0 ms	25.0 ms	Comfortably under the 100 ms target.
Screenshot encode	107	83.7 ms	88.0 ms	132.0 ms	Usually under the 150 ms target; max observed was 171 ms.
Planner grid overlay	107	141.0 ms	150.0 ms	185.0 ms	Extra cost for coordinate rulers and element markers.
UI perception	107	2280.8 ms	2052.0 ms	4000.0 ms	Largest local overhead; UIA/perception is the main optimization target.
Ollama/model call	107	9757.1 ms	7579.0 ms	23694.0 ms	Dominant end-to-end cost, as expected.
Tool execution	107	140.1 ms	5.0 ms	188.0 ms	Includes one explicit wait outlier at about 5 seconds.
Verification capture	107	80.0 ms	87.0 ms	128.0 ms	Post-action screenshot verification.
Metrics collection	108	53.0 ms	51.0 ms	68.0 ms	CPU/RAM/GPU sampling overhead.

Derived loop overhead from the same timing log:

Aggregate	Average	P50	P95	Interpretation
Core non-LLM overhead, excluding perception and settle delay	370.1 ms	250.0 ms	568.0 ms	Includes screenshot capture/encode, execution, verification, and metrics.
Core non-LLM overhead, excluding perception, settle delay, and wait actions	239.7 ms	247.0 ms	337.0 ms	Closer to normal click/type/keypress loop overhead.
Non-LLM overhead with perception, excluding settle delay	2769.5 ms	2419.0 ms	4569.0 ms	Shows the cost of UI perception on top of screenshot/execute work.
Non-LLM overhead with perception and settle delay	3763.0 ms	3562.5 ms	5575.0 ms	Reflects the default post-action settle delay for mutating actions.

session_write_ms is not present in the current timing records, so JSON/session-write overhead is not benchmarked in this snapshot.

Requirements

• Windows desktop session.
• Python 3.10 or newer. Python 3.11+ is recommended.
• Ollama running locally at http://127.0.0.1:11434.
• At least one installed Ollama vision model.
• Node.js and npm for the React frontend.
• Rust and Cargo for the Tauri desktop shell.

Quick Start

cd E:\ComputerUse

py -3.11 -m venv .venv
.\.venv\Scripts\Activate.ps1

python -m pip install --upgrade pip
python -m pip install -e .

npm install --prefix apps\desktop

Start the desktop app:

npm run desktop:dev

The Tauri app starts the Python worker with:

python -m computeruse.worker

For the smoothest local setup, launch the desktop app from a shell where the intended Python environment is already active.

Desktop App

The first screen is the task runner, not a landing page.

Panel	What it does
Task runner	Enter a natural-language task, choose dry-run mode, set max steps, and run/pause/resume/stop.
Model selector	Lists installed Ollama models with known vision models ranked first.
Screenshot preview	Shows the latest observe or verification capture.
Last action	Displays the validated JSON action returned by the model.
Step timeline	Shows action, thought, confidence, result, and inline failures.
Debug timing	Shows per-phase loop timings when enabled.
History	Lists recent local tracked sessions and step summaries.

Run a task like:

Open Chrome, go to YouTube, search for TWICE, and open the first video.

ComputerUse will keep taking one small action at a time until the model returns done, returns fail, the task is cancelled, or the max-step limit is reached.

CLI

List installed Ollama models:

computeruse models

Capture the current screen:

computeruse screenshot

Run a task:

computeruse run "Open Chrome, go to YouTube, search for TWICE, and open the first video" --model llava:latest

Run without executing mouse or keyboard events:

computeruse run "Open Chrome and go to YouTube" --model llava:latest --dry-run --debug-timing

Start the MCP server:

computeruse mcp

Equivalent module entrypoint:

python -m computeruse.mcp_server

Ollama Models

ComputerUse queries Ollama through the local HTTP API and displays every installed model. Known vision-capable families are ranked first when present:

• LLaVA
• BakLLaVA
• Moondream
• MiniCPM-V
• Qwen VL and Qwen2.5-VL
• Gemma vision-capable variants

Example model install:

ollama pull llava:latest

Action Contract

The model may return exactly one JSON object per turn. No prose, no Markdown, no multiple actions.

{
  "thought": "Use the address bar to navigate directly.",
  "action": "hotkey",
  "args": {
    "keys": ["ctrl", "l"]
  },
  "done": false,
  "confidence": 0.92
}

Supported action names:

screenshot
click
double_click
right_click
move
scroll
drag
click_element
double_click_element
move_element
click_target
move_target
type_text
press
hotkey
wait
done
fail

Coordinate actions use absolute screenshot-pixel coordinates from the latest capture. Element and target actions use the most recent UI Automation/perception data where available.

Use click_element for normal controls: buttons, links, tabs, menus, text fields, checkboxes, browser controls, web results, and app navigation. Use double_click_element only for desktop-style items that conventionally require double-click to open: desktop shortcuts/icons, files, folders, Explorer rows, and open/save dialog file rows. Do not double-click web links, buttons, tabs, YouTube thumbnails, checkboxes, text fields, or menu commands. scroll accepts clicks; negative values scroll down and positive values scroll up. drag performs one atomic click-hold-drag-release with start_x, start_y, end_x, end_y, and optional duration_ms.

Worker Protocol

The GUI talks to the Python worker with newline-delimited JSON over a managed process. The protocol is intentionally small and explicit.

GUI commands:

{"type":"list_models"}
{"type":"start_task","task":"Open Chrome and go to YouTube","model":"llava:latest","dry_run":false,"max_steps":50}
{"type":"pause"}
{"type":"resume"}
{"type":"stop"}
{"type":"take_screenshot"}
{"type":"list_history","limit":50}
{"type":"get_history_session","session_id":"..."}

Worker events:

{"type":"models","models":[{"name":"llava:latest","vision":true}]}
{"type":"session_started","session_id":"..."}
{"type":"screenshot","path":"E:\\ComputerUse\\screenshots\\current.png","width":1920,"height":1080}
{"type":"step_started","step_index":3}
{"type":"model_action","action":{"action":"click","args":{"x":500,"y":300},"confidence":0.82}}
{"type":"tool_result","ok":true,"message":"clicked"}
{"type":"timing","step_index":3,"capture_ms":42,"encode_ms":65,"ollama_ms":1840,"execute_ms":7,"session_write_ms":3}
{"type":"session_done","summary":"The requested page is open."}
{"type":"session_failed","reason":"The browser did not load after repeated attempts."}

MCP Server

ComputerUse includes a stdio MCP server so other agents can use local screen observation and one-step execution safely.

Generic MCP configuration:

{
  "mcpServers": {
    "computeruse": {
      "command": "python",
      "args": ["-m", "computeruse.mcp_server"],
      "cwd": "E:\\ComputerUse"
    }
  }
}

If the MCP client does not inherit your activated shell, point directly at the virtual environment:

{
  "mcpServers": {
    "computeruse": {
      "command": "E:\\ComputerUse\\.venv\\Scripts\\python.exe",
      "args": ["-m", "computeruse.mcp_server"],
      "cwd": "E:\\ComputerUse"
    }
  }
}

Codex TOML example:

[mcp_servers.computeruse]
command = 'E:\ComputerUse\.venv\Scripts\python.exe'
args = ['-m', 'computeruse.mcp_server']
cwd = 'E:\ComputerUse'
startup_timeout_sec = 120

Recommended MCP workflow:

1. Call computeruse_help.
2. Call computeruse_start_session with the user task.
3. Call computeruse_observe.
4. Call computeruse_execute_step with exactly one validated action.
5. Inspect the verification observation.
6. Repeat observe/execute until complete.
7. Call computeruse_finish_session.

Runtime Files

These files are local runtime state and are ignored by Git:

Path	Purpose
sessions/active_session.json	Current active task state.
screenshots/current.png	Latest raw screenshot.
screenshots/planner.png	Planner screenshot with rulers and element markers.
logs/debug_timing.jsonl	Timing and resource metrics.
data/computeruse.sqlite3	Local run history and step summaries.

The runtime does not need cloud storage. Keep these artifacts private unless you deliberately redact and share them.

Safety Model

ComputerUse is designed around narrow, validated actions:

• The planner cannot run shell commands or arbitrary Python.
• The runtime validates every model action before execution.
• Dry-run mode validates model actions without moving the mouse or typing.
• Pause and stop are available from the desktop UI.
• Passwords, payment details, tokens, destructive changes, purchases, posts, and security-setting changes require explicit user intent before they should be executed.
• Web pages are treated as untrusted input.

Project Layout

apps/
  desktop/                 Tauri 2 + React + TypeScript app
computeruse/
  agent/                   loop, prompts, Ollama client, session and history logic
  schemas/                 Pydantic action and session models
  tools/                   screenshots, screen metadata, mouse, keyboard, windows, executor
  cli.py                   Typer CLI
  worker.py                newline-delimited JSON worker for the GUI
  mcp_server.py            stdio MCP server
data/                      local SQLite history, ignored by Git
logs/                      debug timing logs, ignored by Git
screenshots/               current/planner captures, ignored by Git
sessions/                  active session JSON, ignored by Git

Development

Frontend typecheck:

npm run desktop:typecheck

Frontend/Tauri build:

npm run desktop:build

Python package install in editable mode:

python -m pip install -e .

Troubleshooting

Symptom	Check
No models appear	Confirm Ollama is running and ollama list shows installed models.
Worker fails to start	Activate .venv, reinstall with python -m pip install -e ., then relaunch Tauri from that shell.
Screenshot does not update	Check that the app has access to the active Windows desktop session.
Actions land in the wrong place	Use the latest screenshot and verify DPI/monitor coordinates; avoid stale screenshots.
Tauri cannot find Rust tooling	Install Rust/Cargo and restart the shell.

Status

ComputerUse is an MVP local automation tool. Treat real desktop control as powerful and potentially disruptive: start with dry runs, keep tasks specific, and verify the screen after each action.