GitHub Copilot for Senior Developers: Visual Studio 2026, VS Code & CLI
A course for senior developers at Big 4 and other professional-services firms who already use GitHub Copilot — or are about to be told to — and want to use it as an engineer rather than as a faster autocomplete. Copilot in 2026 is an agent platform: agent mode and a Plan agent in Visual Studio 2026 and VS Code, specialised agents for debugging, profiling, testing and .NET modernisation, custom agents and skills your team keeps in the repository, MCP servers, cloud agents that return pull requests, and Copilot CLI in the terminal. The course teaches the skills that separate a senior from a passenger: engineering the context, splitting a task into a plan the agent can execute, reviewing an AI diff as critically as a colleague's, encoding team rules once so they work in every IDE, and knowing exactly what leaves the client's perimeter — and what it costs in AI Credits. Every capability is taught the same way: the pain that makes you reach for it, the capability itself, and its cost — including the uncomfortable ones, such as content exclusion not applying in agent mode, or a green test suite that an agent wrote to match its own bug. The mandatory track follows the official GH-300 (GitHub Copilot) exam outline, so the course doubles as certification preparation; optional units go deeper into Copilot CLI automation, hooks, model and cost engineering, and measuring real productivity. Labs use one sample repository — Aldervane Advisory LLP's ENGAGE platform — that opens in Visual Studio 2026, VS Code and the CLI alike; it is a public GitHub template (github.com/AndreyKuralekh/engage), so each learner starts from their own copy. Every lab also has a read-and-answer path for learners without a Copilot Business or Enterprise seat.
Path through the course
· 25 unitsthe order is free · the steps below are the order the author suggests, not a conditionView: map · steps
Stage 1
~1 h
Stage 2
~3 h
A · Foundations · by the author’s design, after “Course map: plans, AI Credits, setting up Visual Studio 2026 and VS Code, the ENGAGE repository”
Stage 3
~3.5 h
4 · A · Foundations · by the author’s design, after “How Copilot works: prompt building, context, proxy filtering, post-processing, suggestion lifecycle”
~1.5 h
17 · E · Governance & exam · by the author’s design, after “Responsible use: risks, hallucinated APIs, insecure patterns, output ownership, verification discipline”
~2 h
Stage 4
~6 h
5 · B · Visual Studio 2026 · by the author’s design, after “Context engineering and prompting: #-references, participants, zero/few-shot, chat history, fresh sessions”
~1 h
9 · C · VS Code & team customisation · by the author’s design, after “Context engineering and prompting: #-references, participants, zero/few-shot, chat history, fresh sessions”
VS Code: Chat, Plan, agent sessions, the Agents window, model choice and its price
~1.5 h
18 · E · Governance & exam · by the author’s design, after “Governance: organisation policies, content exclusion and its gaps, public code filter, audit log, REST API for seats, AI Credit budgets”
Aldervane case: the February confidentiality incident — root causes across the whole course
~1.5 h
19 · E · Governance & exam · by the author’s design, after “Context engineering and prompting: #-references, participants, zero/few-shot, chat history, fresh sessions”
~1 h
25 · Optional · Beyond the exam · by the author’s design, after “Governance: organisation policies, content exclusion and its gaps, public code filter, audit log, REST API for seats, AI Credit budgets”
Measuring impact and rolling Copilot out to a team: metrics, adoption, avoiding vendor numbers
~1 h
Stage 5
~6.5 h
6 · B · Visual Studio 2026 · by the author’s design, after “Visual Studio 2026 basics: inline suggestions, Next Edit Suggestions, Chat, Copilot Actions, commit messages”
Agent mode in Visual Studio: tools, approvals, the build/test loop, Plan agent → Implement plan
~1.5 h
10 · C · VS Code & team customisation · by the author’s design, after “VS Code: Chat, Plan, agent sessions, the Agents window, model choice and its price”
~1.5 h
20 · E · Governance & exam · by the author’s design, after “Aldervane case: the February confidentiality incident — root causes across the whole course”, “Copilot CLI essentials: install, interactive sessions, plan and autopilot, permissions, key commands, scripts and files”
Exam rehearsal: GH-300 formats, traps by domain, time management
~1.5 h
21 · Optional · Beyond the exam · by the author’s design, after “Copilot CLI essentials: install, interactive sessions, plan and autopilot, permissions, key commands, scripts and files”
Copilot CLI at work: sessions, delegation to the cloud agent, plugins and custom agents
~1 h
24 · Optional · Beyond the exam · by the author’s design, after “VS Code: Chat, Plan, agent sessions, the Agents window, model choice and its price”
Models, BYOK and cost engineering under AI Credits
~1 h
Stage 6
~6 h
7 · B · Visual Studio 2026 · by the author’s design, after “Agent mode in Visual Studio: tools, approvals, the build/test loop, Plan agent → Implement plan”
Built-in agents in Visual Studio: @debugger, @profiler, @test, @git review
~1.5 h
11 · C · VS Code & team customisation · by the author’s design, after “Team rules: copilot-instructions.md, *.instructions.md with applyTo, prompt files, organisation instructions — and what VS and the CLI see”
Custom agents and agent skills: team roles and procedures in the repository
~2 h
13 · D · Quality & teamwork · by the author’s design, after any one of these: “Agent mode in Visual Studio: tools, approvals, the build/test loop, Plan agent → Implement plan”, “VS Code: Chat, Plan, agent sessions, the Agents window, model choice and its price”
~1.5 h
22 · Optional · Beyond the exam · by the author’s design, after “Copilot CLI at work: sessions, delegation to the cloud agent, plugins and custom agents”
Copilot CLI in automation: non-interactive runs, preToolUse hooks, scripts and CI
~1 h
Stage 7
~6 h
8 · B · Visual Studio 2026 · by the author’s design, after “Built-in agents in Visual Studio: @debugger, @profiler, @test, @git review”
Lab: modernising Engage.Legacy.Import with @modernize (.NET Framework 4.8 → .NET 10)
~2 h
12 · C · VS Code & team customisation · by the author’s design, after “Custom agents and agent skills: team roles and procedures in the repository”
~1.5 h
14 · D · Quality & teamwork · by the author’s design, after “Testing with Copilot: unit and integration tests, edge cases, assertions — and why an agent's green tests prove little”
~1.5 h
23 · Optional · Beyond the exam · by the author’s design, after “Custom agents and agent skills: team roles and procedures in the repository”
Hooks and guardrails in VS Code: agent hooks, scoped hooks in custom agents, failure semantics
~1 h
Stage 8
~1.5 h
15 · D · Quality & teamwork · by the author’s design, after “Security and performance review: Review Selection, Copilot code review on pull requests, and judging AI findings”
The cloud agent: from issue to pull request, reviewing an agent's PR, and when delegation pays off
~1.5 h
Stage 9
~1 h
16 · D · Quality & teamwork · by the author’s design, after “The cloud agent: from issue to pull request, reviewing an agent's PR, and when delegation pays off”
Spaces, PR summaries and review standards in instruction files (and Spark, briefly)
~1 h
Exam
closed · enrol on the course
final · in the browser, without the assistant
Exam
The path in words
- Stage 1 · Course map: plans, AI Credits, setting up Visual Studio 2026 and VS Code, the ENGAGE repository — ~1 h
- Stage 2 · How Copilot works: prompt building, context, proxy filtering, post-processing, suggestion lifecycle — by the author’s design, after “Course map: plans, AI Credits, setting up Visual Studio 2026 and VS Code, the ENGAGE repository”; ~1.5 h
- Stage 2 · Responsible use: risks, hallucinated APIs, insecure patterns, output ownership, verification discipline — by the author’s design, after “Course map: plans, AI Credits, setting up Visual Studio 2026 and VS Code, the ENGAGE repository”; ~1.5 h
- Stage 3 · Context engineering and prompting: #-references, participants, zero/few-shot, chat history, fresh sessions — by the author’s design, after “How Copilot works: prompt building, context, proxy filtering, post-processing, suggestion lifecycle”; ~1.5 h
- Stage 3 · Governance: organisation policies, content exclusion and its gaps, public code filter, audit log, REST API for seats, AI Credit budgets — by the author’s design, after “Responsible use: risks, hallucinated APIs, insecure patterns, output ownership, verification discipline”; ~2 h
- Stage 4 · Visual Studio 2026 basics: inline suggestions, Next Edit Suggestions, Chat, Copilot Actions, commit messages — by the author’s design, after “Context engineering and prompting: #-references, participants, zero/few-shot, chat history, fresh sessions”; ~1 h
- Stage 4 · VS Code: Chat, Plan, agent sessions, the Agents window, model choice and its price — by the author’s design, after “Context engineering and prompting: #-references, participants, zero/few-shot, chat history, fresh sessions”; ~1.5 h
- Stage 4 · Aldervane case: the February confidentiality incident — root causes across the whole course — by the author’s design, after “Governance: organisation policies, content exclusion and its gaps, public code filter, audit log, REST API for seats, AI Credit budgets”; ~1.5 h
- Stage 4 · Copilot CLI essentials: install, interactive sessions, plan and autopilot, permissions, key commands, scripts and files — by the author’s design, after “Context engineering and prompting: #-references, participants, zero/few-shot, chat history, fresh sessions”; ~1 h
- Stage 4 · Measuring impact and rolling Copilot out to a team: metrics, adoption, avoiding vendor numbers — by the author’s design, after “Governance: organisation policies, content exclusion and its gaps, public code filter, audit log, REST API for seats, AI Credit budgets”; optional; ~1 h
- Stage 5 · Agent mode in Visual Studio: tools, approvals, the build/test loop, Plan agent → Implement plan — by the author’s design, after “Visual Studio 2026 basics: inline suggestions, Next Edit Suggestions, Chat, Copilot Actions, commit messages”; ~1.5 h
- Stage 5 · Team rules: copilot-instructions.md, *.instructions.md with applyTo, prompt files, organisation instructions — and what VS and the CLI see — by the author’s design, after “VS Code: Chat, Plan, agent sessions, the Agents window, model choice and its price”; ~1.5 h
- Stage 5 · Exam rehearsal: GH-300 formats, traps by domain, time management — by the author’s design, after “Aldervane case: the February confidentiality incident — root causes across the whole course”, “Copilot CLI essentials: install, interactive sessions, plan and autopilot, permissions, key commands, scripts and files”; ~1.5 h
- Stage 5 · Copilot CLI at work: sessions, delegation to the cloud agent, plugins and custom agents — by the author’s design, after “Copilot CLI essentials: install, interactive sessions, plan and autopilot, permissions, key commands, scripts and files”; optional; ~1 h
- Stage 5 · Models, BYOK and cost engineering under AI Credits — by the author’s design, after “VS Code: Chat, Plan, agent sessions, the Agents window, model choice and its price”; optional; ~1 h
- Stage 6 · Built-in agents in Visual Studio: @debugger, @profiler, @test, @git review — by the author’s design, after “Agent mode in Visual Studio: tools, approvals, the build/test loop, Plan agent → Implement plan”; ~1.5 h
- Stage 6 · Custom agents and agent skills: team roles and procedures in the repository — by the author’s design, after “Team rules: copilot-instructions.md, *.instructions.md with applyTo, prompt files, organisation instructions — and what VS and the CLI see”; ~2 h
- Stage 6 · Testing with Copilot: unit and integration tests, edge cases, assertions — and why an agent's green tests prove little — by the author’s design, after any one of these: “Agent mode in Visual Studio: tools, approvals, the build/test loop, Plan agent → Implement plan”, “VS Code: Chat, Plan, agent sessions, the Agents window, model choice and its price”; ~1.5 h
- Stage 6 · Copilot CLI in automation: non-interactive runs, preToolUse hooks, scripts and CI — by the author’s design, after “Copilot CLI at work: sessions, delegation to the cloud agent, plugins and custom agents”; optional; ~1 h
- Stage 7 · Lab: modernising Engage.Legacy.Import with @modernize (.NET Framework 4.8 → .NET 10) — by the author’s design, after “Built-in agents in Visual Studio: @debugger, @profiler, @test, @git review”; ~2 h
- Stage 7 · MCP: connecting servers, trust, allowlists and registry policy, data leakage and prompt injection through tools — by the author’s design, after “Custom agents and agent skills: team roles and procedures in the repository”; ~1.5 h
- Stage 7 · Security and performance review: Review Selection, Copilot code review on pull requests, and judging AI findings — by the author’s design, after “Testing with Copilot: unit and integration tests, edge cases, assertions — and why an agent's green tests prove little”; ~1.5 h
- Stage 7 · Hooks and guardrails in VS Code: agent hooks, scoped hooks in custom agents, failure semantics — by the author’s design, after “Custom agents and agent skills: team roles and procedures in the repository”; optional; ~1 h
- Stage 8 · The cloud agent: from issue to pull request, reviewing an agent's PR, and when delegation pays off — by the author’s design, after “Security and performance review: Review Selection, Copilot code review on pull requests, and judging AI findings”; ~1.5 h
- Stage 9 · Spaces, PR summaries and review standards in instruction files (and Spark, briefly) — by the author’s design, after “The cloud agent: from issue to pull request, reviewing an agent's PR, and when delegation pays off”; ~1 h
Programme · 25 units
| 1 | Course map: plans, AI Credits, setting up Visual Studio 2026 and VS Code, the ENGAGE repository Tell which Copilot plan and which contract applies to a developer, and why client code needs an organisation seat | ~1 h |
| 2 | How Copilot works: prompt building, context, proxy filtering, post-processing, suggestion lifecycle Trace a Copilot request through context gathering, prompt building, proxy, filters, model and post-processing | ~1.5 h |
| 3 | Responsible use: risks, hallucinated APIs, insecure patterns, output ownership, verification discipline Name the six responsible-AI principles used in GH-300 and apply them to everyday Copilot work | ~1.5 h |
| 4 | Context engineering and prompting: #-references, participants, zero/few-shot, chat history, fresh sessions Name the five layers of context in a chat prompt and say who controls each | ~1.5 h |
| 5 | Visual Studio 2026 basics: inline suggestions, Next Edit Suggestions, Chat, Copilot Actions, commit messages Control completions and Next Edit Suggestions deliberately: partial acceptance, manual invocation, and the review point between the two NES Tabs | ~1 h |
| 6 | Agent mode in Visual Studio: tools, approvals, the build/test loop, Plan agent → Implement plan Choose between Ask, the Plan agent and agent mode for a task, and explain how Copilot Edits and Agent (Preview) relate to them | ~1.5 h |
| 7 | Built-in agents in Visual Studio: @debugger, @profiler, @test, @git review Pick the right built-in agent for a debugging, performance, testing or pre-commit review task | ~1.5 h |
| 8 | Lab: modernising Engage.Legacy.Import with @modernize (.NET Framework 4.8 → .NET 10) Install and start the GitHub Copilot modernization agent in Visual Studio and scope it to one project | ~2 h |
