agent-customization
**WORKFLOW SKILL** — Create, update, review, fix, or debug VS Code agent customization files (.instructions.md, .prompt.md, .agent.md, SKILL.md, copilot-instructions.md, AGENTS.md). USE FOR: saving coding preferences; troubleshooting why instructions/skills/agents are ignored or not invoked; configuring applyTo patterns; defining tool restrictions; creating custom agent modes or specialized workflows; packaging domain knowledge; fixing YAML frontmatter syntax. DO NOT USE FOR: general coding questions (use default agent); runtime debugging or error diagnosis; MCP server configuration (use MCP docs directly); VS Code extension development. INVOKES: file system tools (read/write customization files), ask-questions tool (interview user for requirements), subagents for codebase exploration. FOR SINGLE OPERATIONS: For quick YAML frontmatter fixes or creating a single file from a known pattern, edit the file directly — no skill needed.
Install
With your agent
Install OMGSkills skill "microsoft/vscode:agent-customization" into this agent's normal skills directory: call the OMGSkills MCP get_install_plan tool for your agent and run the script it returns (it installs only the pinned commit and verifies SKILL.md), and stop if MCP or the pin is unavailable. Do not overwrite or change existing skills without asking me.
Manual command
git clone https://github.com/microsoft/vscode /tmp/vscode && ln -s /tmp/vscode/extensions/copilot/assets/prompts/skills/agent-customization ~/.claude/skills/agent-customizationFrom README
Agent Customization Decision Flow | Primitive | When to Use | |-----------|-------------| | agent instructions | Always-on, applies everywhere in the project | | File Instructions | Explicit via applyTo patterns, or on-demand via description | | MCP | Integrates external systems, APIs, or data | | Hooks | Deterministic shell commands at agent lifecycle points (block tools, auto-format, inject context) | | Custom Agents | Subagents for context isolation, or multi-stage workflows with tool restrictions | | Prompts | Single focused task with parameterized inputs | | Skills | On-demand workflow with bundled assets (scripts/templates) | Quick Reference Consult the reference docs for templates, domain examples, advanced frontmatter options, asset organization, anti-patterns, and creation checklists. If the references are not enough, load the official documentation links for each primitive.
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