LensSmith — errors where you are looking

LensSmith writes errors, warnings and messages right at the end of the line they belong to, and tints the line by the problem. No more hovering over squiggles or looking down at the Error List.

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📖 Documentation · Visual Studio 2022 and 2026 · x64 and ARM64 · UI in 14 languages

Same code, read in a second

In the code

Each line shows its most serious problem: a round icon, the diagnostic code and the text, in the color of its level. When a line has more, +N tells how many; hover the message to read all of them in full. Messages (suggestions such as IDE0017) are blue and quieter than errors and warnings, so they do not drown them out.

XAML, finally

A wrong property value, an unknown type, a typo in an attribute — the XAML editor underlines them, but the text used to hide in the Error List. LensSmith writes it next to the line, so a mistake is seen right away, not at build or run time.

Quiet while you type

Lines you are editing stay calm until you pause (500 ms by default), so half-typed code does not flash errors at you. Long texts are shortened with "…" to fit the window; a compact mode shows only the code.

Line tint for every theme

A soft gradient behind the line, fading to the right, makes problems visible even while scrolling. Dark themes are all different, so there are three styles — gradient, solid, or only a bar at the left edge — and three strengths. Each level can be tinted or not. Four color schemes — normal, bright, soft and monochrome — change the colors of the messages too.

Where it works

C#, Visual Basic and F#, C++, TypeScript and JavaScript, XAML — any editor where Visual Studio draws squiggles. In XAML the text comes from the Error List, since the XAML editor shows its squiggles without text. Files that nothing checks while you edit them — .idl, CMake lists, .props — show the errors of the last build from the Error List. Only visible lines are read and drawn, so even a file with thousands of lines stays fast.

Settings

Tools → Options → SmithWorks → LensSmith. Choose which levels to show and tint, hide single codes (for example IDE0008), change the pause after typing and the tint style. Every option has a description, and a live preview shows the result.

Questions or ideas? Use the Q & A tab on this page or the Feedback repository. Full documentation: lazowskianton.github.io/VSExtensions/lenssmith.