VS Code Copilot

Host entry

An IDE extension host runs inside VS Code, JetBrains, or another editor and receives workspace/editor context through that host's extension APIs.

Host owns

The editor owns activation, command palette placement, sidebar/chat UI, extension storage, trust prompts, and workspace permission boundaries.

Connector role

agent-connector targets documented extension-readable config, MCP, commands, skills, rules, and memory files without claiming control of the IDE. Current wired connector surfaces: MCP server, Hooks, Commands, Skills, Subagents, Memory.

Implementation consequence

Extension surfaces must distinguish file-backed connector artifacts from UI affordances that only the editor or marketplace extension can expose. No visible host-native gap is currently tracked for this surface.

Source pass

Current source review findings are kept as the first architecture section so readers can separate external evidence from the generated local coverage model.

• The public tracker is archived and deprecated, which makes the row a product/extension evidence surface rather than an implementation source.
• The repository scope is VS Code Copilot Chat and completions UX feedback, so this host remains an IDE extension row rather than a CLI row.
• Because the public tracker points feedback elsewhere, architecture claims should stay tied to documented extension behavior and local adapter metadata.

Runtime boundary

The adapter target is the VS Code extension and agent runtime. VS Code owns the editor window, chat surfaces, local agent harness, integrated terminal, workspace trust, extension tools, permissions, and background session UI.

• VS Code exposes an Agents window, Chat view, inline chat, and quick chat as separate user surfaces.
• Local agents run inside the editor harness, while Copilot CLI sessions run outside VS Code in the background.
• The connector page must not collapse the VS Code host with Copilot CLI even though VS Code can start and monitor CLI sessions.

MCP registration

MCP is first-class in VS Code agent customization. The docs distinguish adding servers, managing server trust, enabling or disabling servers, synchronizing configuration, and centrally managing access, so connector writes need to respect editor policy boundaries.

• MCP servers extend chat with external tools and can be added through the VS Code agent customization path.
• Trust, sandboxing, and centrally managed access are host-owned policy surfaces.
• Copilot CLI has its own MCP limitations and should be documented separately from VS Code local agents.

Hook bridge

VS Code documents agent hooks as a preview customization surface. agent-connector should treat this as an editor-native hook system, while keeping current adapter support tied to the exact generated files and event envelopes it can verify.

• Hooks belong to agent customization rather than ordinary chat commands.
• Preview status means the page should avoid over-promising stable hook semantics.
• Hook support is distinct from MCP tools and from Copilot CLI's separate hook surface.

Content surfaces

VS Code agent content includes instructions, agent skills, custom agents, prompt files, memory, and workspace context. These are editor-scoped content surfaces that interact with settings, workspace files, and extension APIs rather than a pure terminal dot directory.

• Slash commands and prompt files are user-facing shortcuts, not lifecycle hooks.
• Memory is a documented agent surface and should be separated from repository instructions.
• Custom agents and subagents define personas and task decomposition inside the VS Code agent UX.

Marketplace and host-only affordances

The host-only story is VS Code's integrated agent control plane: multiple chat surfaces, extension-contributed tools, MCP, hooks, custom agents, notifications, checkpoints, and Copilot CLI handoff from one editor shell.

• Extension-contributed tools are available to VS Code local agents but not necessarily to Copilot CLI sessions.
• The archive should show VS Code as an editor host with both local and delegated background agents.

Host-specific shape

VS Code Copilot is an editor-extension host: the UI and activation live inside VS Code, while agent-connector targets the local Copilot-compatible MCP, hooks, skills, commands, subagents, and memory surfaces.

• Form factor: Extension.
• Native surfaces: MCP server, Hooks, Commands, Skills, Subagents, Memory.
• Wired surfaces: MCP server, Hooks, Commands, Skills, Subagents, Memory.
• Visible gaps: none.

Hooks

Hooks enter through a host-launched command that exchanges event JSON over stdio.

MCP

The adapter writes this host's native MCP registration dialect, including its root key, scope, transport fields, and environment syntax.

Memory

Managed memory text is written into the rules or memory file this host actually reads, with ownership markers for reversible uninstall.

Marketplace and affordances

Current install is a direct native-file write path; any package artifact is manual unless a driver is added.

• Runtime handlers: none.
• User-visible affordances: Users see managed commands + skills + subagents + memory surfaces after install; runtime-only surfaces stay behind the host boundary..