Click a DOM element in Chrome/Edge. Two ways to target: (1) selector — a CSS selector (combines browser_locate + mouse_click; stable across repaints); or (2) by-axis (semantic) — by:'text'|'regex'|'role'|'ariaLabel' + pattern, so you do not have to build a CSS selector for dynamic-class SPAs. by-axis resolves to a SINGLE actionable element (climbing to a clickable ancestor up to 3 levels, hit-testing for occlusion) and STOPS with code:'BrowserAmbiguousTarget' (candidates[] + next[] hints) when 2+ actionable elements match, or code:'BrowserNoActionableTarget' when matches exist but none is clickable — it never guesses. If the target is behind a modal dialog blocking the page, BOTH targeting modes STOP with code:'BrowserModalBlocking' (context.blockingElement {name, role}) instead of clicking through to the backdrop — dismiss the dialog (its close button or Escape) and retry; a plain navigation drawer does not count as blocking. Optionally add role to filter (by:'text',pattern:'Save',role:'button') and scope to narrow the search. Provide EITHER selector OR by+pattern (not both). Pass tabId+port so the server auto-guards (verifies tab readyState and identity) and returns post.perception.status. lensId is optional for advanced pinned-tab workflows. Caveats: selector mode fails if the element is outside the visible viewport — scroll it into view with browser_eval("document.querySelector('sel').scrollIntoView()") first (by-axis only resolves in-viewport actionable targets). hints.verifyDelivery:{status:'delivered'|'unverifiable', reason, observedSignals:{mutationCount,urlChanged,activeElementChanged}} reports the post-click observation in 2 values: 'delivered' fires only when mutationCount>0 OR urlChanged (activeElementChanged is recorded in observedSignals but intentionally NOT a delivery signal — plain clicks on focusable controls always update focus, treating that as 'delivered' would mask silent-fail regressions); 'unverifiable' reason ∈ {'iframe_context_mismatch','no_dom_mutation','probe_install_failed','probe_read_failed'}. CDP emits 2 values only (focus_only is a UIA-path concept, N/A here). BrowserClickNotDelivered is reserved-only (false-positive risk too high to emit) — degradation reads from 'unverifiable' status.

Purpose: Inspect or operate on a browser tab via 3 actions: 'js' (evaluate JS), 'dom' (get HTML), 'appState' (extract SSR-injected SPA state). Details: action='js' — Run a JS expression. withPerception:true wraps in {ok, result, post}. action='dom' — Return outerHTML of selector (or document.body), truncated to maxLength. action='appState' — Scan Next/Nuxt/Remix/Apollo/GitHub/Redux SSR injected JSON; pass selectors to override defaults. Prefer: Use action='appState' BEFORE 'dom' or 'js' on SPAs where rendered HTML is sparse — single CDP call. Use 'dom' when 'appState' is empty and you need page structure. Use 'js' as the escape hatch for arbitrary scripting. Caveats: DOM nodes cannot be returned from action='js' directly (circular refs are serialized safely). React/Vue/Svelte controlled inputs cannot be set via element.value — use keyboard(action='type') / browser_fill instead. readyState is strictly checked; guard blocks if page is still loading. Typed errors: code:'BrowserNotConnected' on CDP disconnect (re-attach via browser_open); code:'AutoGuardBlocked' when the auto-guard refuses (e.g. page still loading) — the error message preserves the guard's 1-sentence recommended next step (most often wait_until({condition:'ready_state'}) or browser_eval readyState polling, then retry). Examples: browser_eval({action:'js', expression:'document.title'}) → page title browser_eval({action:'dom', selector:'#main', maxLength:5000}) → outerHTML browser_eval({action:'appState'}) → default SPA state probes

Fill a form input with a value via CDP — works on React/Vue/Svelte controlled inputs that reject browser_eval value assignment. Two ways to target: (1) selector — a CSS selector (use browser_overview / browser_locate to find one); or (2) by-axis (semantic) — by:'text'|'regex'|'role'|'ariaLabel' + pattern (e.g. by:'ariaLabel', pattern:'Email address', or by:'role', pattern:'textbox'), so you do not have to build a CSS selector. by-axis resolves to a SINGLE fillable element and STOPS with code:'BrowserAmbiguousTarget' (candidates[] + next[] hints) when 2+ match, or code:'BrowserNoActionableTarget' when the match is not a fillable input/textarea/contenteditable — it never guesses. Optionally add role to filter and scope to narrow. Provide EITHER selector OR by+pattern (not both). Use this over browser_eval when setting a controlled input's value via JS does not update framework state. Caveats: Requires browser_open (CDP active). actual in the response shows the element's value after fill; verify it matches the intended value. Typed errors: code:'BrowserFillNotDelivered' on post-fill value mismatch — note the false-positive case where a React controlled input's onChange transforms the value (delivery actually succeeded; hints.verifyDelivery.subReason:'controlled_input_transform' for that case; the actual value is authoritative).

Inspect all form fields (input, select, textarea, button) within a CSS-selector-specified container and return their name, type, id, current value, hint text, disabled/readOnly state, and associated label text (resolved via for[id], ancestor LABEL, aria-labelledby, aria-label in that order). Use this before browser_fill to discover exact field selectors and avoid accidentally targeting the wrong input (e.g. a global search bar). Caveats: Requires browser_open (CDP active). Hidden inputs (type=hidden) are excluded by default — set includeHidden:true if needed. Value text is truncated at 200 chars.

Find a DOM element by CSS selector and return its physical screen coordinates — compatible directly with mouse_click. Prefer browser_click to find+click in one step. Prefer browser_overview to discover selectors. Caveats: Coordinates are captured at call time; if the page reflows before mouse_click, coords may be stale. Typed errors: code:'BrowserNotConnected' (call browser_open first), code:'ElementNotFound' (selector did not match — re-discover via browser_overview / browser_search).

Navigate a browser tab to a URL via CDP Page.navigate — more reliable than clicking the address bar. Pass tabId+port so the server auto-guards (verifies tab readyState) and returns post.perception.status. lensId is optional for advanced pinned-tab workflows. Caveats: Does not block until page load completes — the Page.navigate ack confirms only that the navigation request was accepted (frameStoppedLoading / loaderId observation is internal). Follow with wait_until({condition:'ready_state' or 'element_matches'}) or repeated browser_eval polling for slow pages. Typed errors: code:'NavigateFailed' (Page.navigate rejected — DNS failure, malformed URL, network unreachable; check URL + connectivity), code:'BrowserNotConnected' (CDP disconnect — re-attach via browser_open), code:'AutoGuardBlocked' when the auto-guard refuses (e.g. tab still loading) — the error message preserves the guard's 1-sentence recommended next step (most often wait_until({condition:'ready_state'}) then retry).

Connect to Chrome/Edge running with --remote-debugging-port and return open tab IDs — required before all other browser_* tools. Pass launch:{} (or with overrides) to auto-spawn a debug-mode browser when no CDP endpoint is live (idempotent: an already-running endpoint is preferred). Returns tabs[] with id, url, title, active — pass tabId to browser_* tools to target a specific tab. Caveats: CDP connection is per-process; if Chrome restarts, call browser_open again to get fresh tab IDs. A Chrome session started without --remote-debugging-port cannot be taken over — close it first or use a separate userDataDir. If the CDP endpoint is unreachable and launch is omitted, returns ok:false (typically code:'BrowserNotConnected' when the fetch surfaces ECONNREFUSED, otherwise code:'ToolError' with error 'Cannot reach Chrome/Edge CDP...'); re-call with launch:{} (idempotent) to auto-spawn or start Chrome manually with --remote-debugging-port=9222.

List all interactive elements (links, buttons, inputs, ARIA controls) on the current page with CSS selectors, visible text or value for inputs, and viewport status — use before browser_click to discover stable selectors, and prefer this over screenshot when verifying button/toggle state after submission (no image tokens, structured output). scope limits to a CSS subsection (e.g. '.sidebar'). Returns state (checked/pressed/selected/expanded) for ARIA custom controls. Also returns a modal: section — whether a true modal dialog is blocking the page (isModal + blocker {name, role} + the signals it was judged on); it is ALWAYS present (isModal:false when no modal), and a navigation drawer is NOT reported as a modal (only an aria-modal / alertdialog / native showModal dialog, or a backdrop-backed dialog that locks the page, is treated as modal). Caveats: Selectors are CDP-generated snapshots — re-call after page navigates or re-renders. Input text reflects the empty-field hint text when defined (takes priority over typed value) — use browser_eval('document.querySelector(sel).value') to read actual typed content. Typed errors: code:'BrowserNotConnected' (CDP not attached — call browser_open or browser_open({launch:{}})). Note: a non-matching scope CSS selector silently falls back to the full document (does not raise an error) — verify the selector via browser_eval if scoped enumeration is required.

Grep-like element search across the current page. by: 'text' (literal substring), 'regex', 'role', 'ariaLabel', 'selector' (CSS). Returns results[] sorted by confidence descending — pass results[0].selector to browser_click. Pagination via offset/maxResults. Caveats: Use browser_overview for broad discovery; use browser_search when you know specific text or role to target. Typed errors: code:'BrowserSearchNoResults' (broaden the by:'text' substring or relax the by:'regex' pattern; switch to browser_overview to enumerate selectors), code:'BrowserSearchTimeout' (reduce maxResults / narrow scope), code:'ScopeNotFound' (the scope CSS selector did not match — verify the selector or omit scope), code:'BrowserNotConnected' (call browser_open first, or browser_open({launch:{}}) to auto-spawn).

Invoke a UI element by name or automationId via UIA InvokePattern — no screen coordinates needed. The server auto-guards using windowTitle (verifies identity, foreground, modal) and returns post.perception.status. Prefer over mouse_click for buttons, menu items, and links in native Windows apps. Use desktop_discover first to discover automationIds. Pass fixId from a suggestedFix to re-target after window identity drift. lensId is optional for advanced pinned-lens use. Caveats: Typed errors: code:'InvokePatternNotSupported' — the control does not expose InvokePattern, fall back to mouse_click; code:'ElementDisabled' — the element is in a disabled state, re-check preconditions before retry; code:'GuardFailed' — read the perception envelope (attention / guard fields) and choose recovery (re-focus, wait, or pass the suggestedFix.fixId on the next call). Some custom controls do not expose InvokePattern at all; fall back to mouse_click for those.

Read or write the Windows clipboard. action='read' returns current text content (empty string if non-text). action='write' replaces clipboard with given text and verifies delivery via Get-Clipboard -Raw read-back, comparing the bytes (UTF-16LE) for exact equality. Caveats: Non-text clipboard payloads (images, files) return empty string on read. Overwrites existing clipboard content on write. action='write' delivery-verification failure returns code:'ClipboardWriteNotDelivered' — typical causes: a third-party clipboard manager intercepts SetClipboardData, DLP / endpoint protection blocks the payload, RDP / Citrix clipboard transcoding strips the text, or another process clears the clipboard between Set and the read-back. Recovery: retry the write, or fall back to keyboard(action='type', use_clipboard=false) for short text. Examples: clipboard({action:'write', text:'hello'}) → write+verify; clipboard({action:'read'}) → returns current text.

Purpose: Read-only observation of the current desktop state. Returns focused window/element, modal flag, attention signal from Auto Perception. Phase 4 absorbs former get_active_window / get_cursor_position / get_screen_info / get_document_state via include* flags. Details: Always returns: focusedWindow (title, hwnd, processName), focusedElement (name, type, value, automationId), cursorPos {x,y}, cursorOverElement (name, type), cursorOverWindow, hasModal (boolean), pageState ('ready'|'loading'|'dialog'), attention, visibleWindows count. Optional fields (default off): includeCursor:true → cursor {x,y,monitorId} (richer than cursorPos). includeScreen:true → screen {virtualScreen, displays[], displayCount, primaryIndex}. includeDocument:true → document {url, title, readyState, selection, scroll, viewport} via CDP (silently omitted on non-Chromium foreground). includeSessionContext:true (or include:['sessionContext']) → sessionContext {origin, consoleSessionId, sessionLabel, sessionState, ownWinStation} for Terminal Services session classification (ADR-017, observability-only). Chromium: cursorOverElement is null (UIA sparse); focusedElement may fall back to CDP document.activeElement; hints.focusedElementSource reports which path produced the row ('view' = engine-perception latest_focus, 'uia' = direct UIA query, 'cdp' = document.activeElement). Does NOT enumerate descendants — use desktop_discover for actionable entity list and window list. Prefer: Use after each action to confirm state. Cheapest observation tool — cheaper than any screenshot. attention='ok' means safe to proceed; other values require recovery (see suggest[]). Set include* flags only when you need the extra data (each adds one syscall or CDP round-trip). Caveats: Cannot detect non-UIA elements (custom-drawn UIs, game overlays). hasModal only detects modal dialogs exposed via UIA — browser alert/confirm dialogs may not appear here. includeDocument requires browser_open (CDP active); silently omitted otherwise with hints.documentUnavailable.

Purpose: Author and run VBA macros against Excel via COM late binding (ADR-015). Headline differentiator against Claude for Excel which writes formulas but cannot run VBA. Details: action='run_vba' authors a Sub in a fresh workbook, saves into the managed Trusted Location (%LOCALAPPDATA%\desktop-touch-mcp\trusted-vba), and Application.Run the macro. Requires HKCU AccessVBOM=1 + VBAWarnings=1 + a registered Trusted Location (all configured by node scripts/enable-access-vbom.mjs). Trust setup: Excel must restart after the CLI runs (values cached at process start). action='check_access_vbom' is a read-only preflight returning {trusted, lockedByPolicy, scope}. Prefer: Run check_access_vbom first when a workflow depends on macro execution; the remediation hint pre-empts an opaque HRESULT 0x800a03ec failure inside run_vba. Caveats: macroName MUST appear as Sub <name>(...) in code (else VbaMacroNotFound). VBA Editor UI is structurally bypassed — no UIA tree walk needed. Excel COM is STA: each call serialises through the bridge's worker thread, so long-running macros block subsequent excel() calls on the same MCP server. Examples: excel({action:'check_access_vbom'}) → {trusted:true, scope:'hkcu'} excel({action:'run_vba', code:'Sub DesktopTouchAdHoc()\n Range("A1").Value = "Hello"\nEnd Sub'}) → {ok:true, workbookPath:'...\trusted-vba\dt_vba_.xlsm'} excel({action:'run_vba', code:'Sub Demo()\n MsgBox "hi"\nEnd Sub', macroName:'Demo', visible:true}) → demo recording path

Bring a window to the foreground by partial title match (case-insensitive). Use when a tool does not accept a windowTitle param, or when you need to switch focus before a sequence of actions. Use chromeTabUrlContains to activate a specific Chrome/Edge tab by URL substring before focusing — only the active tab's title appears in the windows list. If CDP is unavailable, chromeTabUrlContains is silently skipped — check response.hints.warnings. Returns WindowNotFound if no match exists; call desktop_discover to see available titles. Caveats: On some apps focus may be immediately stolen back (modal dialogs, UAC prompts) — verify with desktop_state after focusing. Win11 foreground refusal (UIPI cross-elevation / admin-only target / call from a background process or service) returns code:'ForegroundRestricted' ok:false instead of silently failing — recover by switching to a tool that does not require foreground transfer: desktop_act / click_element use UIA InvokePattern (no foreground needed); keyboard BG path bypasses foreground for terminal-class targets only (Windows Terminal / cmd / PowerShell — keyboard with windowTitle on non-terminal apps still hits the same ForegroundRestricted refusal). browser_* tools target by tabId/selector, not windowTitle.

Purpose: Send keyboard input to a window: 'type' for text, 'press' for key combos, 'sequence' for atomic multi-step chords. Details: action='type' inserts text (auto-clipboard for non-ASCII / IME-safe). action='press' sends key combos like 'ctrl+c'/'alt+tab'. action='sequence' runs ordered steps in one keyboard lock — use for Alt+letter, letter mnemonic chains where intermediate tool calls would close the menu. Pass windowTitle to auto-focus and auto-guard (identity, foreground, modal) before input. Omitting windowTitle acts on the active window (unguarded). Prefer: Use windowTitle to auto-focus before injection. Set lensId for perception guards. Use desktop_act({action:'setValue'}) for UIA ValuePattern text fields. Caveats: win+r/win+x/win+s/win+l blocked. action='type' does not handle CJK IME composition — use use_clipboard=true or desktop_act({action:'setValue'}). Non-ASCII text (CJK / emoji / diacritics / smart-quote-class punctuation) auto-clipboards to prevent silent-drop and Chrome accelerator hijack; pass forceKeystrokes:true to disable. Background (PostMessage/WM_CHAR) auto-engages for terminal-class windows (Windows Terminal / cmd / PowerShell); DTM_BG_AUTO=1 enables globally. Foreground non-terminal type runs a per-chunk leash; user focus-steal mid-stream aborts with FocusLostDuringType + context.typed/remaining; pass abortOnFocusLoss:false to disable. BG type verifies WM_CHAR via UIA TextPattern read-back; mismatch returns BackgroundInputNotDelivered (see SUGGESTS for false-positive notes). BG press read-back is scoped to terminal-class + enter/tab/arrow; other combos return verifyDelivery:'unverifiable', failure returns BackgroundKeyNotDelivered. action='sequence' is FG-only (BG/foreground_flash schema-rejected); emits verifyDelivery:'focus_only'; mid-loop focus theft returns MenuFocusLostMidSequence + context.remaining: Step[]. Win11 FG refusal returns ForegroundRestricted — terminal-class targets auto-engage BG; non-terminal switch to desktop_act / click_element. Examples: keyboard({action:'type', text:'hello', windowTitle:'Notepad'}) → text injected (guarded) keyboard({action:'type', text:'hello'}) → text injected (unguarded) keyboard({action:'press', keys:'ctrl+c'}) → copy keyboard({action:'press', keys:'escape', windowTitle:'Dialog'}) → dismiss dialog keyboard({action:'sequence', steps:[{keys:'alt+i', gapMs:100},{keys:'m'}], windowTitle:'Microsoft Visual Basic'}) → Insert > Module (atomic)

Click at screen coordinates. Normally pass windowTitle so the server auto-guards the click (verifies target identity, foreground, coordinate is inside the target rect) and returns post.perception without a confirmation screenshot. origin+scale from dotByDot=true screenshots are converted to screen coords before guarding. doubleClick:true for double-click; tripleClick:true for triple-click (selects a full line of text). Prefer click_element (UIA) for native apps, prefer browser_click for Chrome. Examples: mouse_click({windowTitle:'Notepad', x:200, y:150}) // guarded — post.perception.status='ok'. mouse_click({x:100, y:100}) // unguarded — post.perception.status='unguarded'. If a guard failure returns a suggestedFix, pass its fixId to approve the fix: mouse_click({fixId:'fix-...'}) // one-shot, expires in 15s. lensId is optional and only for advanced pinned-target workflows; omit it for normal use. Caveats: origin+scale are meaningful ONLY with dotByDot=true screenshot responses. hints.verifyDelivery:{status:'delivered'|'focus_only'|'unverifiable', reason} reports the post-click observation in 3 values (focused-element shift, window-foreground change, or no signal). Win11 foreground refusal during the homing path (UIPI cross-elevation / admin-only target / call from a background process or service) returns code:'ForegroundRestricted' ok:false rather than landing the click on the wrong window — recover by switching to a tool that accepts windowTitle directly (click_element / desktop_act) — browser_* tools target by tabId/selector, not windowTitle. MouseClickNotDelivered is reserved-only (false-positive risk is too high to emit a typed code), so degradation is expressed via the 'unverifiable' status, not a separate error.

Click and drag from (startX, startY) to (endX, endY) holding the left mouse button — for sliders, drag-and-drop, canvas drawing, and window resizing. Pass windowTitle so the server auto-guards the start coordinate and returns post.perception. Examples: mouse_drag({windowTitle:'Notepad', startX:50, startY:50, endX:200, endY:200}). lensId is optional and only for advanced pinned-target workflows. Caveats: Left button only. Both start and endpoint are guarded. Cross-window and desktop drags are blocked by default — pass allowCrossWindowDrag:true to confirm intent. hints.verifyDelivery:{status:'delivered'|'focus_only'|'unverifiable', reason} reports the post-drop observation in the same 3-value shape as mouse_click. MouseDragNotDelivered is SUGGESTS-registered but reserved-only (not emitted) — degradation is expressed via the 'unverifiable' status rather than a typed code. Win11 foreground refusal (UIPI cross-elevation / admin-only target / call from a background process or service) returns code:'ForegroundRestricted' ok:false from the homing path.

Show a Windows system tray balloon notification to alert the user. Use at the end of a long-running task so the user knows it finished without watching the screen. Caveats: toast の user reach は原理的に観測不能 (matrix §3.1 line 158 規範整合)。Focus Assist (Do Not Disturb) / Notifications-off setting / consent UI sink いずれも tool 側からは判別不能のため、successful response は常に hints.verifyDelivery を含む (status="unverifiable", reason="user_visible_side_effect_uninspectable", channel="win32_balloon_tip" — 全 double-quoted JSON literal)。caller は user 側の post-notification behavior (例: wait_until(focus_changes)) で間接観測することが望ましい。Uses System.Windows.Forms — no external modules needed.

Purpose: Execute multiple tools sequentially in one MCP call — eliminates round-trip latency for predictable multi-step workflows. Details: steps[] is an array of {tool, params} objects. Accepts all desktop-touch tools plus a special sleep pseudo-step: {tool:"sleep", params:{ms:N}} (max 10000ms per step). stop_on_error=true (default) halts on first failure. Max 50 steps. The LLM cannot inspect intermediate results during execution — all steps run to completion (or first error) before any output is returned. Prefer: Use for predictable fixed sequences (focus → sleep → type → screenshot). Do not use for conditional logic — return to the LLM between branches so it can inspect intermediate state. Caveats: If any step may fail conditionally (e.g. a dialog that may or may not appear), split the macro at that point. Each screenshot step within a macro incurs the same token cost as a standalone call. Examples: [{tool:'focus_window',params:{windowTitle:'Notepad'}},{tool:'sleep',params:{ms:300}},{tool:'keyboard',params:{action:'type',text:'Hello'}},{tool:'screenshot',params:{detail:'text',windowTitle:'Notepad'}}] [{tool:'browser_navigate',params:{url:'https://example.com'}},{tool:'wait_until',params:{condition:'element_matches',target:{by:'text',pattern:'Example Domain'}}}]

Purpose: Capture desktop, window, or region across detail levels (meta / text / image / som / ocr) and capture modes (normal / background). Details: detail='meta' (default) returns window titles+positions only (~20 tok/window, no image). detail='text' returns UIA actionable elements with clickAt coords, no image (~100-300 tok). detail='som' returns a Set-of-Marks annotated image plus OCR-detected elements with IDs (bypasses UIA entirely). detail='ocr' returns Windows OCR words with screen-pixel clickAt coords (Phase 4: absorbs former screenshot_ocr — use when UIA is sparse and you want to force OCR unconditionally). detail='image' and detail='som' are server-blocked unless confirmImage=true is also passed. mode='background' captures hidden/minimised/occluded windows via PrintWindow (Phase 4: absorbs former screenshot_background) — pair with windowTitle/hwnd. dotByDot=true returns 1:1 pixel WebP; compute screen coords: screen_x = origin_x + image_x (or screen_x = origin_x + image_x / scale when dotByDotMaxDimension is set — scale printed in response). diffMode=true returns only changed windows after the first call (~160 tok). region={x,y,width,height} captures a sub-rectangle (Phase 4: absorbs former scope_element when paired with windowTitle/hwnd — discover element bounds via desktop_discover, then pass region here). Data reduction: grayscale=true (−50%), dotByDotMaxDimension=1280 (caps longest edge), windowTitle+region (sub-crop to exclude browser chrome — e.g. region={x:0, y:120, width:1920, height:900}). Prefer: Use meta to orient, text before clicking, dotByDot only when precise pixel coords are needed. Use detail='som' for native apps or games that do not expose UIA elements (UIA-Blind). Use detail='ocr' for OCR-only (skip UIA entirely). Use mode='background' when the target window must stay hidden or cannot be brought to foreground. Prefer browser_* tools for Chrome. Use diffMode after actions to confirm state changed. Only use image+confirmImage when text returned 0 actionable elements and visual inspection is genuinely required. Caveats: Default mode scales to maxDimension=768 — image pixels ≠ screen pixels; apply the scale formula before passing to mouse_click. Foreground detail='image' is always blocked without confirmImage=true. diffMode requires a prior full-capture baseline (non-diff call or workspace_snapshot) — calling diffMode cold returns a full frame, not a diff. mode='background' requires windowTitle or hwnd, and only composes with detail in {'image','meta'} — detail='text'/'som'/'ocr' run only against foreground capture (the dispatcher rejects the conflicting combination). Passing mode='background' is itself the acknowledgement that image pixels are wanted, so confirmImage is NOT required for it (matches the former screenshot_background contract). fullContent=false enables legacy mode (faster but GPU windows may be black). detail='ocr' requires windowTitle or hwnd; first call may take ~1s (WinRT cold-start) and the matching OCR language pack must be installed. Examples: screenshot() → meta orientation of all windows screenshot({detail:'text', windowTitle:'Notepad'}) → clickable elements with coords screenshot({detail:'ocr', windowTitle:'PDF', ocrLanguage:'ja'}) → OCR words with screen-pixel coords screenshot({mode:'background', windowTitle:'Chrome', dotByDot:true, dotByDotMaxDimension:1280, grayscale:true}) → background-capture pixel-accurate Chrome screenshot({windowTitle:'Notepad', region:{x:0,y:120,width:600,height:400}}) → cropped sub-region (zoom into element after desktop_discover)

Purpose: Scroll a window or page. 5 strategies via action: 'raw' (wheel notches), 'to_element' (UIA name/automationId or CSS selector), 'smart' (auto-detect target with multi-strategy fallback), 'capture' (full-page stitched image), 'read' (scroll+OCR+dedupe → stitched text). Details: action='raw': send raw mouse-wheel notches at (x,y) or current cursor, optional window focus. Scroll scale — UIA Tier 1 (ScrollPattern apps): empirically ≈1 text line per notch; amount:3 (default) ≈ 3 lines (small nudge), amount:10 ≈ 10 lines (~½ visible area). Legacy SendInput: each amount unit = 3 wheel ticks; ≈9 text lines per unit at Windows default (app/OS-setting dependent). action='to_element': scroll a named element into viewport (UIA or CDP). action='smart': handles nested scroll layers, virtualised lists, sticky-header occlusion. action='capture': stitches full-page images (caps at ~700KB raw); sizeReduced=true means downscaled. action='read': scrolls page-by-page, OCRs each viewport, deduplicates overlapping lines, returns stitched text; language auto-detected from OS locale if omitted. Prefer: Use action='to_element' or action='smart' for click target out-of-viewport recovery (entity_outside_viewport). Use action='capture' for reading long pages as images. Use action='read' for extracting text from long native-app documents (PDF readers, text editors, terminals) where copy-paste is unavailable. For simple scroll without target, use action='raw'. Caveats: action='capture' returns stitched image — pixels do NOT match screen coords when sizeReduced=true, use for reading only, not mouse_click. action='smart' CDP path requires browser_open. action='to_element' native path requires element to implement UIA ScrollItemPattern. action='read' uses OCR (imperfect accuracy) and requires the window to be visible; for browser pages prefer browser_eval or browser_overview for accurate DOM text. action='raw' typed errors: code:'ScrollNotDelivered' on silent drop (overlay / non-scrollable / UIPI low-IL); already-at-boundary is success via pre/post-percent disambiguation. hints.verifyDelivery.{channel,reason} per ADR-018 §2.6 (Phase 1b: Tier 1 UIA dispatch for HWNDs exposing ScrollPattern; other apps use legacy SendInput). action='smart' typed errors: code:'OverflowHiddenAncestor' (retry with expandHidden:true), code:'VirtualScrollExhausted' (provide virtualIndex). Examples: scroll({action:'raw', direction:'down', amount:5, windowTitle:'Chrome'}) scroll({action:'to_element', name:'OK', windowTitle:'Dialog'}) scroll({action:'smart', target:'#create-release-btn'}) scroll({action:'capture', windowTitle:'Chrome', maxScrolls:10}) scroll({action:'read', windowTitle:'Acrobat', maxPages:15}) // OCR + dedupe long PDF

Return MCP server status. engine: native engine availability — uia: 'native' = Rust UIA addon (~2 ms focus / ~100 ms tree); 'powershell' = PS fallback (~366 ms focus). imageDiff: 'native' = Rust SSE2 SIMD (0.26 ms @ 1080p); 'typescript' = TS fallback (~3.8 ms). health: process diagnostic snapshot (issue #365) — uptimeSec, memory.{rssBytes,heapUsedBytes,heapTotalBytes}, cpu.{userUs,systemUs} (cumulative since startup), shutdown.{pending,graceMs,inflightCount} (pending=true means stdin EOF received and grace timer is running), lastRpc.{receivedAt(ISO),method} (last JSON-RPC request observed on stdio transport; HTTP transport is not tracked). Diagnostic metadata — do not surface unless the user asks about performance/troubleshooting. engine values are stable for the process lifetime; health values change per call.

Purpose: Interact with a terminal window: read output, send input, or run+wait+read in one call. action='read' / action='send' absorb the formerly-standalone read/send tools (Phase 4). Details: action='run' is the recommended high-level workflow: send command → wait until quiet/pattern/timeout → read output. The command text is passed as input (the legacy parameter name command is also accepted as a deprecated alias — see issue #245). Returns completion={reason, elapsedMs} first-class plus outputIntegrity:'ok'|'baseline_lost' so callers can detect when scrollback could not be anchored to the pre-send buffer. action='read' reads current text via UIA TextPattern (falls back to OCR); use sinceMarker for incremental diff. action='send' sends a command with focus management. Prefer: action='run' for command execution + result. For long-running commands (test runners, builds, deploys) use until:{mode:'pattern', pattern:''} — the default quiet mode is tuned for short interactive commands and may complete prematurely on multi-second silent gaps mid-run. Use action='read'/'send' for fine-grained control or when you need to interleave other actions. Caveats: Do not screenshot the terminal — action='read' is cheaper and structured. action='run' supports completion reasons: quiet | pattern_matched | exited | timeout | window_closed | window_not_found | send_failed (send rejected on a live window — see warnings for the underlying error code). until:{mode:'exit', shell:'bash'|'powershell'} (issue #386) returns completion.exitCode + reason:'exited' via an echo-immune sentinel that works for multiline input that pattern mode cannot anchor; pass shell explicitly (auto fails as ExitModeShellAmbiguous on WT/conhost/SSH), cmd is unsupported (ExitModeShellUnsupported), open-construct input is rejected (ExitModeUnsafeInput). When outputIntegrity:'baseline_lost' is returned, output is forced to '' and readError.code='BaselineMarkerLost' is set: rerun with until:{mode:'pattern',...} or longer timeoutMs. action='run' may also emit warnings prefixed FileLockCollision: when output reveals an EBUSY/Windows-lock/EAGAIN-EDEADLK file collision (e.g. shell '>' redirect colliding with the script's own writer — issue #236). Default quietMs=1500 (issue #196); long silences require pattern mode. preferClipboard=true (send default) overwrites clipboard. Hidden-input prompts emit verifyDelivery.unverifiable (reason:'hidden_input_prompt') — use method:'foreground'. action='read' typed errors: TerminalWindowNotFound, TerminalTextPatternUnavailable (force source:'ocr'); stale sinceMarker → hints.terminalMarker.previousMatched:false on ok:true (omit sinceMarker). FG-path Win11 foreground refusal returns code:'ForegroundRestricted' — switch to method:'background' or DTM_BG_AUTO=1. BG path auto-engages only when (a) the target window class is ConsoleWindowClass (conhost: cmd / PowerShell / pwsh classic hosts) OR (b) env DTM_BG_AUTO=1 is set globally. Windows Terminal (CASCADIA_HOSTING_WINDOW_CLASS) is intentionally EXCLUDED from auto-engage (issue #173): WT runs on WinUI/XAML and silently drops WM_CHAR posted to its HWND, so the FG path is used by default — pass sendOptions:{method:'background'} only if you have verified your WT build accepts BG input. Examples: terminal({action:'run', windowTitle:'PowerShell', input:'npm test', until:{mode:'pattern', pattern:'Test Files'}}) → recommended for test runners; matches when vitest summary appears terminal({action:'run', windowTitle:'pwsh', input:'ls'}) → quiet 1500ms wait, returns output (short interactive) terminal({action:'run', windowTitle:'pwsh', command:'ls'}) → identical to the above; command is a deprecated alias of input (issue #245) terminal({action:'read', windowTitle:'PowerShell', sinceMarker:'...'}) → incremental diff using the read action terminal({action:'send', windowTitle:'PowerShell', input:'echo hello'}) → sends text + Enter using the send action

Purpose: Server-side poll for an observable condition — eliminates screenshot-polling loops when waiting for state changes. Details: condition selects what to watch: window_appears/window_disappears (target.windowTitle required), focus_changes (optional target.fromHwnd), element_appears/value_changes (target.windowTitle + target.elementName required, UIA; min 500ms interval), ready_state (target.windowTitle; visible + not minimized), terminal_output_contains (target.windowTitle + target.pattern required [+target.regex:true], needs terminal tools loaded), element_matches (target.by + target.pattern required, needs browser tools loaded), url_matches (target.pattern required [+target.regex:true]; matches the active tab's location.href via CDP — use for SPA route changes, redirects, OAuth flows). Returns {ok:true, elapsedMs, observed} on success, or WaitTimeout error with suggest hints. timeoutMs default 5000 (max 60000). Prefer: Use instead of run_macro({sleep:N}) + screenshot loops. Use terminal_output_contains to detect CLI command completion. Use element_matches for browser DOM readiness after navigation. Use url_matches when the URL is the most reliable signal (SPA routing / redirect cascades). Caveats: terminal_output_contains, element_matches, and url_matches require a browser CDP connection (open --remote-debugging-port=9222 first). element_appears/value_changes spawn a UIA process per poll — interval clamped to 500ms minimum. On elapsed-timeout the response is {ok:false, code:'WaitTimeout', error, suggest:[...]}; the suggest[] array lists three fixed actions: 'Increase timeoutMs', 'Verify the target is correct', 'Inspect intermediate state with screenshot(detail='meta')'. Non-timeout failures also occur — pre-poll validation and missing-hook errors classify as code:'ToolError' (read the descriptive error message), and CDP probe errors (url_matches / element_matches conditions) surface as code:'BrowserNotConnected' (re-attach via browser_open). Branch on code rather than assume WaitTimeout. Examples: wait_until({condition:'window_appears', target:{windowTitle:'Save As'}, timeoutMs:10000}) wait_until({condition:'terminal_output_contains', target:{windowTitle:'Terminal', pattern:'$ '}, timeoutMs:30000}) wait_until({condition:'element_matches', target:{by:'text', pattern:'Submit', scope:'#checkout-form'}}) wait_until({condition:'url_matches', target:{pattern:'/dashboard'}, timeoutMs:15000}) wait_until({condition:'url_matches', target:{pattern:'^https://app\.example\.com/orders/[0-9]+$', regex:true}})

Purpose: Decorate a window: pin (always-on-top), unpin, or dock (move + resize + optional pin). Details: action='pin' makes window always-on-top until unpin/duration_ms. action='unpin' removes always-on-top. action='dock' positions to corner with width/height (default 480×360 bottom-right) and optionally pins. Minimized windows are automatically restored before docking. Prefer: Use action='dock' for terminal/CLI window auto-positioning at session start. Use action='pin' alone when you only need always-on-top without moving or resizing. Caveats: Pin survives minimize/restore; explicit action='unpin' needed to release. Dock fails on elevated processes. Dock overrides any existing Win+Arrow snap arrangement. Examples: window_dock({action:'dock', title:'PowerShell', corner:'bottom-right', width:480, height:360}) window_dock({action:'pin', title:'Settings', duration_ms:5000}) window_dock({action:'unpin', title:'Settings'})

Purpose: Launch an application and wait for its new window to appear, returning title, HWND, and PID. Details: Runs the command via ShellExecute, snapshots the window list before launch, then polls until a new HWND appears (compared by HWND, not title). Returns {windowTitle, hwnd, pid, elapsedMs}. Works for localized window titles (e.g. '電卓' for calc.exe) because detection is HWND-based, not title-based. timeoutMs default 10000. detach=true fires without waiting and returns no window info. Prefer: Use instead of run_macro({exec, sleep, desktop_discover}) combos. Follow with focus_window(windowTitle) to interact with the launched app. Caveats: Single-instance apps that reuse an existing window will not register as a new HWND — call desktop_discover first to check if the window is already open. detach=true returns immediately with no window title or hwnd. Examples: workspace_launch({command:'notepad.exe'}) → {windowTitle:'', hwnd:'...', pid:...} workspace_launch({command:'calc.exe', timeoutMs:15000})

Purpose: Orient fully in one call — returns display layouts, all window thumbnails (WebP), and per-window actionable element lists with clickAt coords. Details: uiSummary.actionable[] per window includes: action ('click'|'type'|'expand'|'select'), clickAt {x,y} (pass directly to mouse_click), value (current text for editable fields). Runs parallel internally; latency ≈ max(single screenshot), not N×screenshots. Also resets the diffMode buffer so subsequent screenshot(diffMode=true) returns only changes (P-frame). Prefer: Use at session start or after major workspace changes. Use screenshot(detail='meta') for cheap re-orientation within a session. Use screenshot(detail='text', windowTitle=X) for a single-window update. Caveats: Thumbnails are scaled, not 1:1 — use screenshot(dotByDot=true, windowTitle=X) for pixel-accurate coords on a specific window after snapshot. Also: this call resets the screenshot diff baseline (I-frame) and identity tracker as a side effect, so subsequent screenshot(diffMode=true) starts fresh from this snapshot. The reset is not currently exposed in causal/working memory — record an explicit 'workspace_snapshot' step if you need to track the reset point in your causal trail (ADR-010 §11 OQ carry-over for full visibility).