feat(screenshot): target a single window via window_name / window_pid

CLAUDE.md

@@ -50,6 +50,7 @@ The codebase follows a layered service architecture under `src/windows_mcp/`:
 - Screenshots are capped to 1920x1080 for token efficiency
 - Mouse/keyboard input uses UIA (same coordinate space as BoundingRectangle; no DPI mismatch)
 - Screenshot is the preferred fast visual-context tool; Snapshot is the heavier path for UI element ids and DOM extraction
+- Both Screenshot and Snapshot accept `window_name` (fuzzy title) or `window_pid` (exact pid) to capture a single window via `desktop/window_resolver.py`; the rect is read with `DwmGetWindowAttribute(DWMWA_EXTENDED_FRAME_BOUNDS)` falling back to `GetWindowRect`
 - Browser detection (Chrome, Edge, Firefox) triggers special DOM extraction mode in Snapshot
 - Fuzzy string matching (`thefuzz`) is used for element name matching
 - UI element fetching has retry logic (`THREAD_MAX_RETRIES=3` in tree service)
@@ -64,6 +65,7 @@ The codebase follows a layered service architecture under `src/windows_mcp/`:
 | `WINDOWS_MCP_PROFILE_SNAPSHOT` | _(off)_ | Set to `1`/`true`/`yes`/`on` to log per-stage timing for Screenshot/Snapshot. Checked in `tools/_snapshot_helpers.py` and `desktop/service.py`. |
 | `ANONYMIZED_TELEMETRY` | `true` | Set to `false` to disable PostHog telemetry. Checked in `__main__.py` and `analytics.py`. |
 | `WINDOWS_MCP_DEBUG` | `false` | Set to `1`/`true`/`yes`/`on` to enable debug mode. Checked in `config.py`. Also available as `--debug` CLI flag. |
+| `WINDOWS_MCP_DISABLE_FLASH` | _(off)_ | Set to `1`/`true`/`yes`/`on` to suppress the orange-red glowing border that briefly appears after every screenshot. Resolved in `desktop/flash_overlay.py`. |
 
 ## Security Context
 

README.md

@@ -446,6 +446,7 @@ All variables are optional unless noted. Set them via the `env` key in `claude_d
 | `WINDOWS_MCP_SCREENSHOT_SCALE` | `1.0` | Scale factor applied to screenshots before encoding. Accepts a float in the range `0.1`–`1.0`. Useful on high-resolution displays (1440p, 4K) where the default produces images that exceed Claude Desktop's 1 MB tool-result limit. Set to `0.5` to halve both dimensions (quarter the file size). |
 | `WINDOWS_MCP_SCREENSHOT_BACKEND` | `auto` | Screenshot capture backend. Accepted values: `auto` (tries dxcam → mss → pillow in order), `dxcam`, `mss`, `pillow`. Use `mss` or `pillow` if `dxcam` is unavailable or causes issues on your GPU. |
 | `WINDOWS_MCP_PROFILE_SNAPSHOT` | _(disabled)_ | Set to `1`, `true`, `yes`, or `on` to emit per-stage timing logs for Screenshot/Snapshot calls. Useful for diagnosing slow captures. |
+| `WINDOWS_MCP_DISABLE_FLASH` | _(disabled)_ | Set to `1`, `true`, `yes`, or `on` to suppress the orange-red glowing border that briefly highlights the captured area after every screenshot. The flash is rendered on a transparent always-on-top window *after* capture so it never appears in the captured image. |
 
 ### Telemetry
 
@@ -493,8 +494,8 @@ MCP Client can access the following tools to interact with Windows:
 - `Move`: Move mouse pointer or drag (set drag=True) to coordinates.
 - `Shortcut`: Press keyboard shortcuts (`Ctrl+c`, `Alt+Tab`, etc).
 - `Wait`: Pause for a defined duration.
-- `Screenshot`: Fast screenshot-first desktop capture with cursor position, active/open windows, and an image. Skips UI tree extraction for speed and should be the default first call when you mainly need visual context. Supports `display=[0]` or `display=[0,1]` to capture specific screens.
-- `Snapshot`: Full desktop state capture for workflows that need interactive element ids, scrollable regions, or `use_dom=True` browser extraction. Supports `use_vision=True` for including screenshots and `display=[0]` or `display=[0,1]` for limiting all returned Snapshot information to specific screens.
+- `Screenshot`: Fast screenshot-first desktop capture with cursor position, active/open windows, and an image. Skips UI tree extraction for speed and should be the default first call when you mainly need visual context. Supports `display=[0]` or `display=[0,1]` to capture specific screens, or `window_name="..."` (fuzzy title match) / `window_pid=12345` (exact process id) to capture just one window's bounding rectangle. The targeted window is brought to the foreground first unless `focus_window=False`. `window_name` / `window_pid` and `display` are mutually exclusive. After capture, a brief orange-red glowing border is drawn over the captured area as a visual confirmation (set `WINDOWS_MCP_DISABLE_FLASH=1` to disable).
+- `Snapshot`: Full desktop state capture for workflows that need interactive element ids, scrollable regions, or `use_dom=True` browser extraction. Supports `use_vision=True` for including screenshots, `display=[0]` or `display=[0,1]` for limiting all returned Snapshot information to specific screens, and `window_name` / `window_pid` for limiting capture to a specific window's bounding rectangle (mutually exclusive with `display`).
 - `App`: To launch an application from the start menu, resize or move the window and switch between apps.
 - `Shell`: To execute PowerShell commands.
 - `Scrape`: To scrape the entire webpage for information.