Claude MCP Guidelines

March 25, 2026 ยท View on GitHub

25-03-2026

Claude-MCP-Guidelines is a snippet for your global ~/.claude/CLAUDE.md that gives Claude deterministic guidance on which MCPs to prefer and when.

The Problem

Two issues with MCP usage in Claude Code:

  1. Missing context: Some MCPs need explanatory guidance that no environment variable provides. Claude might have access to a tool but not know when it's the right choice.
  2. Tool conflicts: When an MCP tool overlaps with Claude's built-in capabilities (e.g., a web-fetch MCP versus Claude's native fetch), which should win? Without guidance, the behaviour is unpredictable.

The Approach

A structured snippet in your home-level CLAUDE.md that:

  • Lists available MCPs with one-line descriptions of when to use each
  • Defines priority rules for conflicts (e.g., "prefer Context7 MCP for documentation lookups over native web fetch")
  • Adds context that helps Claude make better tool selection decisions

Self-Aware Ephemerality

The author (me) explicitly notes this is a short-lived experiment. The expectation is that Anthropic will eventually build better MCP orchestration into the platform itself, making user-level hacks like this unnecessary. But until then, it meaningfully improves MCP invocation predictability.

Practical Takeaway

Even a few lines about MCP preferences in your CLAUDE.md can reduce the randomness of tool selection. If you've got multiple MCPs with overlapping capabilities, explicit guidance is worth adding.

Disclaimer: Experimental snippet. MCP behaviour changes with Claude Code updates, so revisit periodically.

Source