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Showing posts from 2026

Agents can now verify your UI changes without leaving VS Code

Verifying frontend changes always meant a mental context switch: write code, alt-tab to a browser, poke around in DevTools, switch back. Even with a decent dev server, the loop was still manual — and for AI agents, it was essentially broken. Agents could write unit tests for logic, but verifying whether a button actually renders, whether a dialog triggers, or whether a layout holds up? That required a human in the loop. I first tried to tackle this problem by using the Playwright or Chrome Dev-Tools MCP server, but with the February 2026 release of VS Code (1.110) , that changes. Agents can now open, interact with, and inspect your running application directly inside VS Code's integrated browser — closing the development loop without any manual hand-off. How it works When browser agent tools are enabled, Copilot gains access to a set of tools that let it read and interact with pages in the integrated browser. As the agent interacts with the page, it sees updates to page co...

Awesome GitHub Copilot just got awesommer (if that’s a word)

If you've been following the GitHub Copilot ecosystem, you've probably heard of the Awesome GitHub Copilot repo . It launched back in July 2025 with a straightforward goal: give the community a central place to share custom instructions, prompts, and chat modes for tailoring Copilot's AI responses. A lot of people contributed. As a result, the repo now contains 175+ agents, 208+ skills, 176+ instructions, 48+ plugins, 7 agentic workflows, and 3 hooks. And now the maintainers took it one step further and created an Awesome GitHub Copilot website and Learning hub . A website that actually helps you find things The new site lives at awesome-copilot.github.com and wraps the repo in a browsable interface built on GitHub Pages. The headline feature is full-text search across every resource — agents, skills, instructions, hooks, workflows, and plugins — with category filters to narrow things down. Each resource has its own page with a modal preview, so you can see exac...

Shining a light on .NET versions across our organisation with OpenTelemetry

At our organisation running a large fleet of .NET services, a deceptively simple question can be surprisingly hard to answer: what versions of .NET are our apps actually running in production? You'd think this would be easy. It isn't. Services get deployed, teams move on, and before long nobody is quite sure whether that one legacy service is still on .NET 6 — or even .NET Core 3.1. Spreadsheets fall out of date. README files lie. The only source of truth is what's actually running. We solved this with three lines of OpenTelemetry configuration. The problem We run dozens of .NET services across multiple teams. We are the middle of a push to .NET 10, but we have no reliable, centralised way to see the current state. We wanted to answer questions like: Which services are still on end-of-life .NET versions? Which teams still have work to do? After a migration wave, how do we confirm everything moved? The solution We already had OpenTelemetry set up ac...

VS Code Memory Tool: Local Memory meets GitHub Copilot Memory

A few weeks ago I wrote about Copilot Memory in VS Code - the GitHub-hosted system that lets Copilot learn repository-specific insights across agents. Since then, VS Code has shipped a second, complementary memory system: the Memory tool . These two systems solve related but distinct problems, and understanding both helps you get the most out of Copilot in your daily workflow. What is the Memory Tool? The Memory tool is a built-in agent capability that stores notes locally on your machine . Unlike Copilot Memory, which lives on GitHub's servers and requires a GitHub repo to function, the Memory tool writes plain files to your local filesystem and reads them back at the start of each session. You enable or disable it with the github.copilot.chat.tools.memory.enabled setting. It's on by default. Three memory scopes VSCode organizes memories into three scopes: Scope Persists across sessions Persists across workspaces Good for ...

DeepWiki - Talk to your documentation

I regularly clone repos on Github. I explore other codebases to learn other coding approaches and improve my understanding of specific libraries. Sometimes these repos have good documentation available but most of the time I end up spelunking through source files trying to reverse-engineer what this thing does. Until I discovered DeepWiki DeepWiki is built to fix that. What is DeepWiki? Launched by Cognition AI — the team behind Devin — DeepWiki is the free public version of their internal Devin Wiki and Devin Search tools, designed to help developers quickly understand complex codebases. The idea is simple: whether it's a public repository or a private project, DeepWiki generates Wikipedia-like documentation pages through simple operations. The quickest way to try it? Just replace github.com with deepwiki.com in any public repo URL. If your repo is not indexed yet, you can ask to index it. Enter an email and you are good to go.   That's it. No install, no acc...

SQL Server silently renames your user when you ALTER with a login

With all this AI features available, you would expect that you no longer loose time on stupid issues. Unfortunately, we are not there yet. I lost a chunk of time today to a behavior in SQL Server that, once you know it, is totally obvious — but until then is absolutely maddening. I'm sharing it here so hopefully you don't lose the same time I did. The setup I had a script meant to be idempotent: create a database user if it doesn't exist, or update it if it does. Standard stuff. Here's a simplified version: Looks fine, right? Run it once — works. Run it a second time and SQL Server throws an error saying it can't find usr_SampleDB_reader . The user you just created. In the same database. With the same script. What's actually happening When you run ALTER USER [...] WITH LOGIN = [...] , SQL Server renames the user to match the login name — by default, silently, without a warning. So after the first run, usr_SampleDB_reader no longer exists. It's...

Compile-Time options validation with the OptionsValidator source generator

In the previous post, we looked at how to implement IValidateOptions<T> by hand — writing a dedicated validator class, injecting services, and expressing cross-property constraints that Data Annotations can't handle. That approach gives you full control and is the right tool when validation logic is genuinely complex. While researching that post I discovered another feature that's worth knowing about: when your validation can be expressed with Data Annotation attributes, the options validation source generator (available since .NET 8) will write the IValidateOptions<T> implementation for you at compile time. You get the safety of startup validation without the boilerplate, and as a bonus the generated code is reflection-free and AOT-compatible. The problem with runtime data annotations Before the source generator existed, the standard way to add annotation-based validation was ValidateDataAnnotations() : This works, but it uses reflection at runtime to ...

Validating configuration at startup with IValidateOptions in .NET

When you build .NET applications with strongly typed configuration, IOptions<T> and its variants give you a clean way to bind appsettings.json sections to C# classes. But binding isn't the same as validating - a missing required value or an out-of-range number will happily bind to a default and silently break your app at runtime. IValidateOptions<T> is the hook .NET provides to fix that. The problem: silent misconfiguration Consider a typical options class: If Host is missing from appsettings.json , your app starts fine. The failure surfaces only when the first email is sent — in production, at 2 AM. Data Annotations ( [Required] , [Range] ) combined with ValidateDataAnnotations() help, but they fall short when you need: Cross-property validation (e.g., Port must be 465 when UseSsl is true ) Async or database-backed checks Conditional logic depending on environment Reusable validators shared across multiple options types This is where I...

How to explore multiple solutions in parallel when using Github Copilot

If you've ever been mid-session with Copilot and thought "I want to try a completely different approach, but I don't want to lose everything I've built up here" — the new /fork command is exactly what you've been waiting for. Shipped in the February 2026 release of VS Code, /fork lets you branch a chat session into a new, fully independent thread — complete with the full conversation history — so you can explore an alternative direction without touching the original. The problem it solves Until now, exploring multiple design options or implementation strategies with Copilot meant one of two things: Start a new session — losing all the context you've already established. Stay in the same session — making your conversation messy and hard to track. Neither is great. Especially for larger tasks where the agent has already built up a useful mental model of your codebase, intent, and constraints. How to use /fork There are two ways to ...

You no longer have to wait for Copilot to finish thinking

There's a specific kind of frustration familiar to anyone who's used an AI coding agent: you send a request, it starts running, and thirty seconds later you realize you forgot to add a critical constraint. Or you think of a follow-up. Or you can see it heading somewhere wrong, and there's nothing you can do but sit there and watch. That's been the workflow. One prompt, one response, wait, repeat. The February 2026 release of VSCode (1.110) changes this in a way that's simple to describe but surprisingly powerful in practice: you can now send messages while a request is still running. What's actually changed The new behavior covers two distinct scenarios. The first is mid-flight intervention : if Copilot is in the middle of generating a response and you realize it's going in the wrong direction, you can now type a corrective message immediately. You don't have to wait. The agent incorporates your guidance and adjusts course without restarting the se...

GitHub Copilot CLI Tips & Tricks — Part 5: Delegation

We've covered modes, session management, parallelization with /fleet , and hooks. To close out the series, we're looking at delegation, the feature that lets you hand off work from your terminal to a background agent in the cloud, and build a network of specialized custom agents for your team. Two flavors of delegation "Delegation" in Copilot CLI means two related but distinct things: /delegate — handing off a task to the Copilot coding agent in the cloud, which works asynchronously on GitHub while you continue with other work Custom agents + /agent — routing tasks to specialized subagents tailored to specific types of work, running locally within your CLI session Both follow the same principle: rather than one generalist agent handling everything, you route work to whatever agent is best suited for the job. Let's look at each in turn. /delegate — Offload to the cloud What it does Running /delegate TASK-DESCRIPTION commits any unstaged ch...

GitHub Copilot CLI Tips & Tricks — Part 4: Automating and enforcing policies with hooks

So far in this series we've covered modes, session management, and parallelization with /fleet . This post is about hooks — one of the more powerful features of Copilot CLI. Hooks let you inject your own shell scripts at key moments during a session, enabling everything from audit logging to blocking dangerous commands before they execute. What are hooks? Hooks are custom scripts that run at specific points during a Copilot CLI session. They receive structured JSON input describing what's happening at that moment — which tool is being called, what arguments it received, what the session context looks like — and can optionally respond with a JSON output that influences what Copilot does next. The key thing that makes hooks different from just writing good prompts or instructions: hooks are deterministic. They execute your code at specific lifecycle points with guaranteed outcomes. Unlike instructions that guide agent behavior, a hook can guarantee that a dangerous comman...

GitHub Copilot CLI Tips & Tricks — Part 3: Parallelizing Work

In the previous posts we covered the different CLI modes and session management. This time we're looking at one of Copilot CLI's most powerful features: the /fleet command. If you've ever wished you could clone yourself to tackle several parts of a codebase at once, this is the closest thing to it. What is /fleet ? When you send a prompt to Copilot CLI, by default a single agent works through the task sequentially. /fleet changes that model entirely. The /fleet slash command lets Copilot CLI break down a complex request into smaller tasks and run them in parallel, maximizing efficiency and throughput. The main Copilot agent analyzes the prompt and determines whether it can be divided into smaller subtasks. It then acts as an orchestrator, managing the workflow and dependencies between those subtasks, each handled by a separate subagent. In practice, this means a task that might take 20 minutes sequentially can complete in a fraction of the time — because independ...