GitHub Copilot
GitHub.comVS CodeVisual StudioJetBrainsEclipseXcodeCLICopilot SDK
GitHub Copilot is strongest on repo, org, and enterprise sharing across GitHub surfaces. The customization cheat sheet explicitly lists Custom Instructions, Prompt Files, Custom Agents, Subagents, Agent Skills, Hooks, and MCP with a full surface support matrix. Custom agents can be centralized at organization or enterprise level in a `.github-private` repository. CLI plugins are the distribution unit that bundles agents, skills, hooks, commands, MCP, and LSP configurations. MCP is supported on all surfaces with toolset customization and enterprise allowlist enforcement. The Copilot SDK (public preview) adds programmatic access to skills, MCP, hooks, and custom agents.
Custom Instructions
InstructionsVendor Terms custom instructions, personal instructions, repository instructions, path-specific instructions, organization instructions, agent instructions, AGENTS.md, CLAUDE.md, GEMINI.md, workspace instructions
Interfaces GitHub.com, VS Code, Visual Studio, JetBrains, Eclipse, Xcode, CLI
Scopes
User / HomeProject / Repo RootSubdirectory / FolderOrganization / Enterprise
Availability current (explicit)
Trust Model Always-on context additions, not hard policy guards; precedence-based concatenation with more specific files overriding broader ones
Notes VS Code and Visual Studio fully supported; JetBrains, Eclipse, Xcode in preview; GitHub.com and CLI supported; precedence order: Personal > Path-specific > Repository-wide > Agent > Organization; organization instructions only on GitHub.com
Agent Skills
SkillsVendor Terms agent skills, skill folders, SKILL.md, allowed-tools, open standard
Interfaces GitHub.com, VS Code, CLI, Copilot SDK
Scopes
Project / Repo RootUser / Home
Availability current (explicit)
Trust Model Loaded when relevant to specialized tasks rather than continuously; can include scripts and resources; allowed-tools frontmatter pre-approves tool usage
Notes VS Code, GitHub.com, CLI, and SDK (public preview) supported; JetBrains in preview; org/enterprise scopes coming soon; based on open Agent Skills standard (agentskills.io)
Prompt Files
PromptsVendor Terms prompt files, reusable prompt templates, slash commands
Interfaces VS Code, Visual Studio, JetBrains, Xcode
Scopes
Project / Repo RootUser / Home
Availability public preview (explicit)
Trust Model Manual, reusable prompt templates with variables and YAML frontmatter; can specify agent mode, model, and tool restrictions per prompt
Notes VS Code and Visual Studio supported; JetBrains and Xcode in preview; not supported on GitHub.com, Eclipse, or CLI; user-level prompt files synced via VS Code Settings Sync
MCP Servers
MCP & ToolsVendor Terms GitHub MCP server, GitHub MCP Registry, MCP servers, MCP toolsets, MCP allowlist
Interfaces GitHub.com, VS Code, Visual Studio, JetBrains, Eclipse, Xcode, CLI, Copilot SDK
Scopes
Machine / AdminProject / Repo RootOrganization / Enterprise
Availability current (explicit)
Trust Model MCP exposes tools and API capabilities subject to OAuth/PAT auth, push protection for secrets, and MCP allowlist enforcement (name/ID matching); enterprise policies override org policies; Registry only mode restricts to approved servers
Notes Available to all GitHub users regardless of plan; GitHub MCP Registry in public preview; org/enterprise can restrict via MCP allowlist policy; toolset customization supported; GitHub MCP server built into CLI; cloud agent has GitHub MCP server and Playwright MCP server by default
Custom Agents
AgentsVendor Terms custom agents, agent profiles, .agent.md files, Copilot cloud agent, Copilot CLI agents
Interfaces GitHub.com, VS Code, JetBrains, Eclipse, Xcode, CLI
Scopes
User / HomeProject / Repo RootOrganization / Enterprise
Availability current (explicit)
Trust Model Specialist persona with its own instructions, tool restrictions, and context; can spin up subagents; enterprise agents override org agents
Notes VS Code, GitHub.com, and CLI supported; JetBrains, Eclipse, Xcode in public preview; enterprise-level agents via .github-private repo; agent-to-agent delegation via agent tool alias
Subagents
AgentsVendor Terms subagents, delegated work, isolated context, temporary agent
Interfaces VS Code, JetBrains, Eclipse, Xcode, CLI
Scopes
Cloud / Web Session
Availability current (explicit)
Trust Model Separate agent spawned by the main agent to handle delegated work in an isolated context window
Notes VS Code and CLI supported; JetBrains, Eclipse, Xcode in preview; not on GitHub.com per cheat sheet; work performed by custom agents is carried out using subagents
Hooks
HooksVendor Terms hooks, lifecycle interceptors, shell commands
Interfaces GitHub.com, VS Code, CLI
Scopes
Project / Repo Root
Availability current (explicit)
Trust Model Deterministic lifecycle interceptors that run synchronously and block agent execution; scripts run with repo-level permissions; receive JSON via stdin; default timeout 30s
Notes GitHub.com and CLI supported; VS Code in preview; 8 hook types: sessionStart, sessionEnd, userPromptSubmitted, preToolUse, postToolUse, agentStop, subagentStop, errorOccurred; only preToolUse can deny tool executions
Policies, Settings, and Content Exclusion
Settings & PolicyVendor Terms policies, feature policies, privacy policies, model policies, AI controls, MCP management, MCP registry, MCP allowlist, content exclusion, IDE settings, policy conflicts
Interfaces GitHub.com, VS Code, Visual Studio, JetBrains, Eclipse, Xcode, CLI
Scopes
User / HomeOrganization / EnterpriseMachine / Admin
Availability current (explicit)
Trust Model Enterprise owners define policies that org owners cannot override; feature, privacy, and model policies control what licensed users can access; MCP allowlists restrict which servers are permitted; content exclusion configurable at repo, org, and enterprise levels
Notes Enterprise AI controls tab with Agents, Copilot, and MCP sections; three policy types: feature, privacy, and models; content exclusion does NOT apply to Copilot CLI, cloud agent, or Agent mode in IDEs; policy conflict resolution uses least-restrictive for most features, most-restrictive for sensitive ones
CLI Plugins
Plugins & DistributionVendor Terms CLI plugins, LSP servers, installable units, marketplace, plugin.json, marketplace.json, commands
Interfaces CLI
Scopes
Project / Repo RootUser / Home
Availability current (explicit)
Trust Model Packaging layer for reuse and team standardization; agents/skills use first-found-wins precedence (project overrides plugin); MCP servers use last-wins (plugin overrides user config)
Notes CLI only; bundles custom agents, skills, hooks, commands, MCP server configurations, and LSP server configurations; two default marketplaces (copilot-plugins, awesome-copilot); cross-tool compatibility with .claude-plugin/ directory; install from marketplace, GitHub repo, Git URL, or local path