# LLM Router — VS Code / GitHub Copilot Routing Rules > These rules apply when using llm-router MCP tools inside VS Code with GitHub Copilot. > VS Code loads MCP servers from .vscode/mcp.json (workspace) or the user mcp.json. > Use `llm_auto` for routing + cross-session savings tracking. --- ## How to Route VS Code loads MCP servers on startup. Once llm-router is registered, call tools by name: ``` Rule: for research/generate/code/analyze tasks → call llm_auto(prompt=) ``` Add to `.github/copilot-instructions.md` for workspace-level routing guidance: ``` When a task requires live web search, call the llm_research MCP tool. For code generation or complex analysis, call llm_code or llm_analyze. For auto-routing with savings tracking, call llm_auto. ``` --- ## Task Type → Tool Mapping | Task | Tool | Notes | |---|---|---| | Simple factual question | `llm_query` | Gemini Flash / Groq | | Research / current events | `llm_research` | Perplexity (web-grounded) | | Writing / content | `llm_generate` | Gemini Flash / Haiku | | Deep analysis | `llm_analyze` | GPT-4o / Gemini Pro | | Code generation | `llm_code` | Ollama → Codex → o3 | | Unknown / auto-detect | `llm_auto` | Classifies + routes | --- ## Savings Visibility Run `llm_savings` in Copilot Chat to see cross-session totals. --- ## Token-Efficient Responses Skip preamble. Lead with result. Fragments fine when meaning is clear. No trailing summaries. ≥3 items → bullets. Never restate the user's request.