# MCP Usage Full Guidance (Archive)

Last Updated: 2026-04-03
Source Rule: `.cursor/rules/mcp-usage.mdc`
Status: Archive companion for pointer rule.

## Purpose

Detailed MCP guidance covering tool selection, cost-aware behavior, and MCP-vs-script routing.

## Core Principles

1. Use production scripts/APIs for deterministic production behavior.
2. Use MCP tools for exploratory analysis, debugging, and ad hoc investigation.
3. Prefer lower-cost data collection paths first (search/fetch) before credit-heavy tools.
4. Keep MCP scope narrow to the active task surface.

## High-Value Routing Notes

- HubSpot: prefer PHP/scripts for bulk audits and reproducible exports; MCP for one-off lookup.
- Firecrawl: prefer scrape markdown mode; avoid extract unless explicitly required.
- SERP research: use Serper when real Google output is required; otherwise free web search.
- Figma: MCP for chat-driven design-to-code; script/API for automation pipelines.
- Excel: MCP for inspection/debugging only; generation remains in production generator scripts.

## Cost/Performance Notes

- Large MCP tool sets can reduce responsiveness; disable low-priority tools when performance degrades.
- Keep prompts direct, and avoid opening broad unrelated docs/rules during MCP tasks.

## Canonical SSOT

- `docs/development/MCP_INTEGRATION.md`
- `.cursor/README-MCP.md`