MCP server tool count vs context window:
MCP server tool count vs context window: 913 tools = dead server. azure-m365-mcp v4.0.0 registered 913 tools (~886KB JSON, ~220K tokens). Every Claude interaction returned Prompt is too big — exceeds 200K context window. Solution: split into two pure-play servers: azure-mcp (561 tools) + m365-mcp (356 tools). Key finding: sentinel_rule_* functions were in graph/security.py but used Azure Management API — always verify API surface, not file location. Rule: Monitor total tool count across all MCP servers. Single server >500 tools = context risk. Combined >2000 deferred tools = budget pressure.