Changelog

Changelog

Home ← # Changelog

[0.2.36] - 2026-07-07

Fixed

• All handlers now return structured JSON instead of hardcoded "ok" — verifiedResult() helper and ~50+ handler functions set Content: []mcp.Content{&mcp.TextContent{Text: "ok"}} which blocked the MCP SDK from auto-populating with the structured second return value. When Content == nil, the SDK marshals the second value and sets both StructuredContent and Content (as JSON text). Fixed verifiedResult() to return nil Content when extra data is present, and changed every handler that returned explicit "ok" Content to return &mcp.CallToolResult{}, map[string]any{"ok": true}, nil (no-data tools) or &mcp.CallToolResult{}, result, nil (data tools). Verified live post-reboot: list_windows, get_system_info, get_active_window, ocr all return their structured JSON payloads instead of "ok".

[0.2.35] - 2026-07-07

Fixed

• roUninitialize never called on shutdown — COM WinRT apartment initialized by ensureRo() was never cleaned up. Added CloseWinRT() in ocr_com.go wired into main.go's signal handler so RoUninitialize runs on graceful shutdown.
• status initializer unreachable in verifiedResult — status := "ok" was always overwritten by the if/else branches before use. Changed to single default status := "ok (verified)" with negation on !vr.Passed.
• klMouseDown and winEventHookProc dead code — leftover scaffolding from keylogger refactor. winEventHookProc type was unused (callback uses syscall.NewCallback inline); klMouseDown was shadowed by local vars in pollLoop. Removed.
• Unused state params in execVerify and execPoll — both functions received *chainState but never used it. Renamed to _ *chainState to match the pattern already used by execWait and execTool. Keeps call-site interface compatibility with execIf/execLoop which do need state.
• Inefficient string concatenation in WriteString calls — three spots in readXlsx and readPdf concatenated strings before passing to buf.WriteString(...), allocating intermediate strings. Changed to fmt.Fprintf(&buf, ...) which avoids the extra allocation.

Added

• uia_set_text MCP tool — writes text into a UI element via UI Automation's ValuePattern.SetValue. The COM plumbing (uiaElement.setValue) existed but was never wired. Added UIASetText() in uia.go, handler and registration in server.go. Fills a backlog item from docs/meta/backlog.md.
• Prior-based coordinate prediction in FindUIElement — priors.go tracked element frequency and position per window but FindUIElement never consulted them. Added FindPriorPrediction() that returns predicted coordinates for high-confidence priors (frequency >= 70%, sample_count >= 5, StdX/StdY <= 2.0). Inserted as step 1.5 in the cascade: memory → prior → ONNX → OCR. A prior hit avoids ONNX (no GPU/CPU inference) and OCR (no PowerShell launch).
• ONNX/OCR failure logging in FindUIElement — when ONNX detection failed, the function silently fell through to OCR with no trace of the error. Same for OCR failure. Added log.Printf calls in both paths so server logs record when these subsystems are unavailable, distinguishing "not found" from "can't detect."
• Competitive intelligence gathered from landscape survey — cross-referenced 12 open-source and commercial projects in docs/comparison-vs-alternatives.md and extracted features worth adopting. Added a "Competitive Intelligence" section to docs/meta/plan.md with prioritized steals (quick wins → medium → high effort). Fleshed out docs/meta/backlog.md with 3 new sections (Memory & ML, Transport & Server, Browser Automation, Linux & Container) and enhanced Security & Identity, Vision, Mouse, Screen, and Processes sections — totaling ~41 new backlog items. Shout out to Cua, Agent-S, Bytebot, MS Magentic-UI, Windows-MCP, DesktopCtl, Windows MCP Server, Computer Control MCP, Browser Use, and Microsoft Windows Recall for the reference implementations and design inspiration.

Fixed

• Double screenshot in FindUIElement OCR fallback — when ONNX failed, OCRScreen("") captured the screen again even though CaptureScreen() had already been called at step 2. Changed OCR fallback to call ocrFromBase64(b64, "") directly, reusing the existing screenshot. Also performs pushRecentOCR/tryCompletePair/LogOCRSnapshot side effects that OCRScreen normally handles.
• Fragile memory deserialization in FindUIElement — the memory fast path used 4 levels of nested type assertions (any → map → float64 → int32) with silent fall-through on any mismatch. Extracted into memoryToElement() helper that returns nil on any parse failure, keeping it clear and testable.

[0.2.34] - 2026-07-07

Fixed

• Training pair pipeline died permanently after a single missed OCR window — LogToolCall only called OCRScreen("") (the auto-capture that completes a pending pair and refreshes recentOCR for the next action) inside the if ocrBefore != "" branch. If one action's findRecentOCRBefore call missed the bridgeWindow — entirely plausible under normal agent round-trip latency between an explicit ocr() call and the action that follows it — the buffer never refreshed again. Every subsequent action would also find nothing, permanently starving training_pairs until something called an OCR tool manually to re-seed it. Moved the OCRScreen("") auto-capture out of the conditional so it now runs after every action regardless of whether that action found a prior snapshot, making the bridge self-healing instead of a single point of failure.

Changed

• bridgeWindow widened 30s → 60s — 30s was tight for realistic agent-driven latency between an OCR call and the action that follows it. Combined with the self-healing refresh above, 60s gives headroom without letting stale context linger indefinitely.

Verification

Live end-to-end test through the MCP server (ocr → click → type → key_press → click → type): before this fix, 5 real actions produced 0 training_pairs rows (the bridge had already gone dark from an earlier missed window). After the fix and a rebuild/restart, the same kind of sequence produced 5/5 pairs, with agent_train/agent_analyze showing populated timing_stats, success_rates, and top_sequences with counts correctly bounded by total_commands.

[0.2.33] - 2026-07-06

Fixed

• agent_analyze: timing_stats/success_rates resetting on restart — Stats were purely in-memory (map[string]*ToolTiming, map[string]*ToolSuccess), so every server restart wiped them, leaving agent_analyze with empty timing_stats/success_rates until new commands arrived. Added adaptive_stats SQLite table and SaveAdaptiveStat()/LoadPersistedStats()/HydratePersisted(). On startup, EnsureAdaptive() calls HydratePersisted() to seed in-memory stats from the durable table, and every RecordResult() call persists the aggregate asynchronously via go SaveAdaptiveStat(...).

• Training token inflation: uniqueTokens() dedup — tokenize() on raw OCR text produced duplicate word entries per row (same word appearing multiple times in the OCR dump contributed multiple hits to the (word, command) pair). This caused Count in top_sequences to exceed total_commands/total_sequences (which count rows, not word occurrences). Added uniqueTokens() to dedupe before insert, so each (word, command) pair gets at most 1 hit per row regardless of how many times the word appears in the OCR context.

• OCR context scoped to nearby words — findRecentOCRBefore() used to pass the ENTIRE screen's OCR dump as ocr_before for every command, so common on-screen words ("the", bullet points, news headlines, unrelated UI labels) all got associated with whatever command followed — producing noise-dominated predictions. Now:

  • For coordinate-based tools (click, move_mouse, drag, hover), it uses word bounding boxes (words []OCRWord) to scope context to words within 200px of the target coordinates, nearest-first, capped at 20 words.
  • For non-coordinate tools, it falls back to capAndDedupeText() which returns at most 40 unique words from the full dump instead of the raw dump.

• LogToolCall no longer double-counts timing/success — LogToolCall previously called Adaptive.RecordResult(tool, 0, errVal == nil) with a phantom 0ms duration. Callers (Click, TypeText, etc.) already call Adaptive.RecordResult with the real elapsed duration. Removed the call from LogToolCall to avoid every action being double-counted with a fake 0ms sample alongside the real one.

Changed

• pushRecentOCR() signature — Now accepts *OCRResult (with word bounding boxes) instead of just string, enabling spatial scoping in findRecentOCRBefore.
• findRecentOCRBefore() signature — Now takes tool string, argsJSON string to enable tool-specific OCR scoping.
• Datalog query limit relaxed — From clamped 50–200 range to 1–5000 range (default 50).

[0.2.32] - 2026-07-05

Fixed

• chain tool startup panic — shared sub-schema pointers — chainInputSchema() reused the same *jsonschema.Schema for then, else, and steps fields. The MCP SDK's AddTool() requires schemas to form a tree (not a DAG) and panics on duplicate pointers. Changed to factory functions that return unique instances per call.
• Module path mismatch — go.mod declared github.com/user/go-mcp-computer-use but the repo lives at github.com/coff33ninja/go-mcp-computer-use. Updated module path and all 7 import references across the codebase. (User was lazy to update this.)
• Adaptive engine: timing_stats and success_rates never populated — RecordCommand (which calls RecordResult → RecordTiming + RecordSuccess) was defined but never called. Added Adaptive.RecordResult(tool, 0, errVal == nil) to LogToolCall so runtime success/failure is tracked per tool. Previously agent_analyze always showed empty timing_stats: {} and success_rates: {}.
• Adaptive engine: rebuildSequences merge corrupts Count and never updates Freq — When merging duplicate (word, command) entries, Count was overwritten instead of accumulated, and Freq (success ratio) was set at creation and never recalculated on merge. Added internal SuccessCount/FailCount fields to SequenceExample, fixed merge to accumulate correctly and recalculate Freq.

Added

• Chain integration tests — 7 tests build-tagged //go:build integration that start the mcp-server binary and validate chain tool end-to-end via stdio MCP protocol. Covers: simple steps, capture, loop, if/else branching, unknown tool error, timeout, and structured data output. Run with go test -tags=integration -v -count=1 -timeout 120s ./internal/actions/ -run 'TestChain_'.
• CI: chain-tests job — runs chain integration tests after lint in .github/workflows/ci.yml.
• README badges — Go version, release, CI status, Windows, MCP, last commit, PRs welcome.

[0.2.31] - 2026-07-05

Changed

• All 60+ query/result handlers now return structured data instead of "ok" — Every handler that returns meaningful data (get_volume, get_battery, list_windows, get_system_info, get_uptime, get_clipboard, get_pixel_color, list_displays, get_disk_usage, get_network_info, ocr, find_image, find_all_images, list_audio_devices, list_processes, uia_find, uia_get_text, memory_get/search/list, template_find/list/store/forget, training_, onnx_, datalog_status, chain, launch_and_wait, write_file, delete_file, find_files, list_directory, set/get_working_directory, bridge_debug, set_config, task_begin, and more) now return their structured JSON data instead of the placeholder "ok" text. The SDK auto-populates tool results from structured output when no explicit TextContent is set, so tools like get_screen_size now show {"width":1920,"height":1080} instead of "ok".
• get_screen_size, get_cursor_position — same fix applied (noticed during audit).
• chain tool schema — no longer rejected by Gemini — IfConfig.Then/Else and LoopConfig.Steps changed from []any to []ChainStep, which produced items: true and type: ["null", "array"] in the auto-generated JSON schema (both rejected by Gemini's MCP schema validator). The chain tool now uses a manually crafted InputSchema that avoids the recursive type cycle in jsonschema-go and produces clean schema output.

[0.2.30] - 2026-07-03

Added

• Windows icon embedded in mcp-server.exe — app.ico compiled into a COFF .syso resource via rsrc (github.com/akavel/rsrc), so the binary shows a custom icon in File Explorer, taskbar, and title bar. Icon sizes: 16, 32, 48, 64, 256px with SVG source in icons/app.svg.
• icons/ directory — app.svg source, generated PNGs at 5 sizes, app.ico multi-res icon, app.rc resource script.
• scripts/gen-icons.ps1 — PowerShell script that runs rsrc to compile app.ico into cmd/mcp-server/rsrc_windows.syso, auto-installing rsrc if missing. Called from build.ps1, lint.ps1, and CI release workflow.

Security

• Bump golang.org/x/net v0.54.0 → v0.55.0 — dependency update from Dependabot patching a security vulnerability in the go_modules group.
• .github/dependabot.yml — package-ecosystem was empty ""; set to "gomod" so Dependabot properly scans go.mod for vulnerabilities.

Changed

• write_file — overwrite is now optional — changed Overwrite bool to *Overwrite *bool with omitempty. No longer required in tool schema, defaults to false when omitted.
• get_file_info — returns metadata instead of "ok" — handler now returns actual file info JSON (name, size, is_dir, mod_time, mode).

[0.2.29] - 2026-07-02

Added

• File System tools — 11 new tools for navigating and manipulating files:
  • list_directory — list files/dirs at path (name, size, is_dir, mod_time, mode)
  • read_file — read file with automatic type detection + native format parsing
  • write_file — write/overwrite files with format-aware creation and editing
  • find_files — recursive glob search (e.g. *.go, **/*.md)
  • copy_file — copy file or directory (recursive)
  • move_file — move/rename file or directory
  • delete_file — delete file/dir to Recycle Bin via SHFileOperationW (not permanent)
  • create_directory — mkdir -p (recursive directory creation)
  • get_file_info — file/dir metadata (size, mod_time, is_dir, mode)
  • set_working_directory — set working directory for relative path resolution
  • get_working_directory — get current working directory
• Format-aware read_file — auto-detects mime type by magic bytes + extension; parses:
  • Plain text (txt, json, csv, yaml, toml, md, source code, configs, etc.) via io.ReadAll
  • .docx via nguyenthenguyen/docx library, extracting text from <w:t> XML elements
  • .xlsx via xuri/excelize/v2, all sheets rendered as TSV
  • .pdf via ledongthuc/pdf, all pages with separators
  • Images (png, jpg, gif, bmp, tiff, webp) via native WinRT COM OCR (ocrNative)
  • Pagination: page and page_size params (default 8000 chars), returns page/totalPages/truncated
• Format-aware write_file — detects target extension and creates/edits:
  • Plain text — raw write via os.WriteFile
  • .docx — new file creates from scratch (ZIP+XML); overwrite preserves existing headers/footers/images by swapping <w:body> content, writes to temp + rename
  • .xlsx — new file via excelize.NewFile(); overwrite opens existing, repopulates cells from TSV content
  • .pdf — new file creates from text via go-pdf/fpdf; overwrite tries pdfcpu.FillFormFile with JSON form field data, falls back to createPdf
• File verification — FilePreCheck/FilePostVerify wired into all 5 action file tool handlers (write, copy, move, delete, create_directory) using ExpConfig / VerifyArgs pattern from v0.2.28
• Recycle Bin delete — delete_file uses SHFileOperationW with FOF_ALLOWUNDO to move items to the Recycle Bin instead of permanent os.RemoveAll
• Working directory — all file tools resolve relative paths against a configurable working directory (defaults to process CWD, changeable via set_working_directory)
• New dependencies — nguyenthenguyen/docx, ledongthuc/pdf, xuri/excelize/v2, go-pdf/fpdf, pdfcpu/pdfcpu for native document parsing and creation

Changed

• internal/actions/filesystem.go — Enhanced ReadFile with format dispatch + pagination; enhanced WriteFile with format-aware creation/editing (docx, xlsx, pdf); file verification helpers; Recycle Bin via SHFileOperationW; working directory support.
• internal/server/server.go — Updated ReadFileArgs{Path, Page, PageSize}, updated write_file tool description; file verification handlers.
• internal/actions/chain.go — Updated chainReadFile with page/page_size params.
• VERSION — bumped to 0.2.29.

Tool Count

Now at 131 total MCP tools (+11).

[0.2.28] - 2026-07-02

Added

• Auto-verify on 5 remaining high-value tools — open_url, launch_app, find_text_and_click, select_all_and_type, click_menu_item now support auto_verify and expected parameters with OCR-based post-action verification, matching the existing 6 tools.
• TrainingCatLaunch category — New "launch" training category for app launch snapshots.
• Pre-action validation (pre_expected) — All 11 verification-enabled tools now accept pre_expected with the same ExpConfig shape (text/not_text/change). Runs OCR before the action and fails fast if precondition not met — action is never executed.
• VerifyArgs embeddable struct — Replaced duplicate AutoVerify/Expected/PreExpected fields across all 11 arg structs with a single VerifyArgs embed, reducing 22 lines of redundancy.
• preVerifyCheck helper — Common pre-verify logic extracted to server.go.
• Region-of-typing OCR — type, type_and_submit, select_all_and_type now capture cursor position (GetCursorPosition) before typing and restrict verification OCR to SmartRegionAround(cursor, 400px) instead of full-screen scan.
• Window-aware OCR for click_menu_item — Verification scans only within the target window bounds (found by FindWindowByTitle + GetWindowState) instead of full screen.
• Coordinate-reuse for find_text_and_click — FindTextAndClick now returns click coordinates (int32, int32, error). The handler uses SmartRegionAround(click_pos, 400px) for post-verify instead of full-screen OCR. Pre-verify uses the specified search region.

Changed

• internal/actions/chained.go — FindTextAndClick signature changed from error → (int32, int32, error). Callers updated: server.go, chain.go, cmd/benchmark/main.go.
• internal/actions/training.go — Added TrainingCatLaunch.
• internal/server/server.go — All 11 verification handlers updated with cursor-aware region (type tools), window-bounds region (click_menu_item), coordinate-reuse region (find_text_and_click), and pre-verify checks. VerifyArgs struct replaces repetitive fields.

[0.2.27] - 2026-06-30

Added

• find_image / find_all_images ONNX + OCR fallback — When NCC template matching fails (no match, degenerate template), both tools now cascade through ONNX YOLO object detection → Windows OCR. find_image returns the highest-confidence ONNX element (or first OCR word if ONNX is empty). find_all_images returns all ONNX elements + all OCR words. The fallback captures a fresh screenshot if no screenB64 was provided (ensureScreenB64), making it robust against degenerate templates.
• findImageONNXFallback / findAllONNXFallback helpers — Extracted fallback logic with full cascade (ONNX → OCR) and screen capture self-healing.
• ensureScreenB64 helper — Captures screen on demand when the passed-in screenB64 is empty, fixing the edge case where degenerate templates bypass screen decode.
• ocr_languages tool — New OcrLanguages() function in ocr.go:145 queries WinRT COM (IOcrEngineStatics.get_AvailableRecognizerLanguages) and returns every installed OCR language with tag, display name, and native name.
• Middle mouse button — Click now supports button: "middle" via mouseEventMiddleDown/mouseEventMiddleUp (0x0020/0x0040).
• Horizontal scroll — Scroll now takes horizontal bool parameter; uses mouseEventHWheel (0x1000) flag when horizontal. chainScroll passes it through from args.

Changed

• internal/actions/template.go — FindImage and FindAllImages restructured: degenerate templates (zero-dim, no-variance) skip NCC entirely and go straight to ONNX+OCR fallback. Template-larger-than-screen still errors (unrecoverable). FindAllImages added as new NCC implementation with non-maximum suppression (overlap >50% suppressed).
• internal/actions/window_ext.go — GetWindowState now returns fullscreen boolean field. Added isFullscreen() helper that checks MonitorFromWindow + GetMonitorInfoW + WS_CAPTION style.
• internal/actions/window_ext.go — Added monitorFromWindow proc, MONITORINFO struct, WS_CAPTION constant.
• docs/tools.md → docs/reference/tools.md — auto-regenerated (2 new tools, 120 total)
• Doc audit & reorganization — Audited 20 files across docs/, dev/, .github/instructions/. Deleted docs/todo.md (dead) and dev/models-setup.md (duplicate of docs/models-setup.md). Deduplicated privacy table, accessibility block, inline tool listing (80 lines), and inline release cycle (8 steps) into cross-references. Reorganized flat docs/ into subdirs: adr/, reference/, guides/, meta/. Moved 15 files to new locations. Updated all cross-references in README.md and all 18 docs files.
• CI/CD path updates — ci.yml references docs/tools.md → docs/reference/tools.md; release.yml references docs/CHANGELOG.md → docs/meta/CHANGELOG.md; scripts/gen-tools-doc.go writes to docs/reference/tools.md; scripts/push-and-release.ps1 references docs/meta/CHANGELOG.md.
• scripts/gen-tools-doc.go — MkdirAll("docs") → MkdirAll("docs/reference"), output path changed from docs/tools.md to docs/reference/tools.md.
• New reference docs — docs/reference/windows-dll-ref.md (every syscall proc, DLL, COM interface used), docs/reference/uipi.md (UIPI elevation detection logic + call sites), docs/reference/com-patterns.md (COM/WinRT patterns: vtable dispatch, async polling, HSTRING/BSTR lifecycle, threading model, UIA tree traversal)
• Cross-reference updates — README.md, codebase-map.md, windows-dll-ref.md all updated with links to the 3 new reference docs
• docs/reference/windows-dll-ref.md — Fixed inaccurate advapi32.dll proc names (removed CheckTokenMembership/AllocateAndInitializeSid/FreeSid that were never used in uipi.go)
• docs/reference/vtable-verification.md — New doc covering COM vtable stability guarantees, SDK header verification procedure, CI/CD plan, and complete test table (13 tests, 16 unique vtbl indices, all verified)

Fixed

• find_image / find_all_images no longer error on degenerate templates — Previously a constant-color or 0×0 template returned an unrecoverable error. Now falls through to ONNX + OCR object/text detection.

VTable Verification System (vtable hardening)

• 36 vtblMethod() call sites annotated — Every COM/WinRT vtable dispatch in uia_com.go, ocr_com.go, ocr.go, winrt.go tagged with inline // N = MethodName (verified 2026-06-30, Win11 26200) and block-level // Verified YYYY-MM-DD — WinBuild SDK headers above each interface definition.
• internal/actions/vtable_test.go — 13 smoke tests with build tag //go:build vtable && windows. Covers all 16 unique vtbl indices used in production: UIA GetRootElement (vtbl 5), BoundingRect (43), FindFirst (5, 21), Conditions (21, 23, 25), GetPropValue (10), GetCurrentPattern (16), ValuePattern/Invoke/Array (3, 4, 6, 21), OCR GetLanguages (7, 6), OCR TryCreate (10), OCR TryCreateFromLanguage (9), StorageFile async pipeline (6, 8, 14, 0, 7), HSTRING round-trip, vtblMethod nil guard. All pass (~8s).
• scripts/verify-vtable-docs.go — Parses all 36 vtblMethod() call sites from source, cross-references each unique index against com-patterns.md and vtable-verification.md doc tables, checks test coverage via // vtbl: annotations. Run go run ./scripts/verify-vtable-docs.go. Confirms all 16 unique indices are documented and tested.
• CI: vtable-check job — .github/workflows/ci.yml runs go test -v -tags=vtable ./internal/actions/ -run 'TestVtable' after build, plus go run ./scripts/verify-vtable-docs.go to catch doc drift.
• go vet passes — zero warnings across all vtable code.
• scripts/verify-iid-usage.go — New Go script that parses winrt.go, scans internal/actions/ for IID references, categorizes each as used (referenced outside winrt.go), internal (only within winrt.go), or unused. Cross-references against the Status column in com-patterns.md docs. With -update, rewrites the Status column. Run: go run ./scripts/verify-iid-usage.go or go run ./scripts/verify-iid-usage.go -update.
• scripts/discover-winrt-iids.ps1 -UpdateDocs mode — Added -UpdateDocs switch that auto-generates the 51-entry IID table in docs/reference/com-patterns.md from discovered values, replacing the content between <!-- IID_TABLE_START --> / <!-- IID_TABLE_END --> markers. Includes fallback pass for statics discovered under flat keys. Now also calls verify-iid-usage.go -update to set correct usage statuses. CI runs -UpdateDocs then go run verify-iid-usage.go then git diff to catch drift.
• ci.yml vtable-check job — Added Verify WinRT IID docs are in sync with source step: runs powershell -File scripts\discover-winrt-iids.ps1 -UpdateDocs + go run ./scripts/verify-iid-usage.go, fails if docs/reference/com-patterns.md has uncommitted changes.
• docs/reference/scripts.md — New reference doc cataloging all 8 scripts with purpose, invocation, uniqueness, and cross-references to docs and CI.
• docs/reference/com-patterns.md — VTable dispatch section (§2) updated with IUnknown base column in all index tables. IID table wrapped in <!-- IID_TABLE_START/END --> markers with new Status column (used/internal/unused). Inline -UpdateDocs flag in both "run the script" instructions.
• docs/reference/vtable-verification.md — Expanded from "proposed plan" to actual test table with vtbl Indices + Verified columns, Performance note documenting why FindAll on desktop root is slow by design, and CI/CD integration reference.
• uia.go andCondition dead code fixed — CreateAndCondition (vtbl 25) was called from buildCondition but not tested; now exercised by TestVtable_IUIAutomation_Conditions.
• internal/actions/uia_ctrltype_test.go — 3 tests validating the UIA ControlTypeId map covers all 41 constants (50000–50040), no duplicates, no out-of-range values, and unknown names return nil.
• Cross-references updated — README.md, docs/reference/codebase-map.md, docs/reference/windows-dll-ref.md, docs/ci-cd-pipeline.md all linked to new vtable docs.
• VTable indices are hard-won — Every index was researched against SDK headers (UIAutomationClient.h, windows.data.h, windows.storage.h) and verified at runtime on Windows 11 (build 26200). These are the most fragile part of the codebase: an incorrect vtbl index silently calls the wrong method or crashes. The verification script and test suite exist because even a single off-by-one error can take days to diagnose. Microsoft freezes these indices for published interfaces, but when upgrading to a new Windows build, run go test -tags=vtable and go run ./scripts/verify-vtable-docs.go before shipping.

... older versions omitted.