MCP Observability is the New APM

In 2010, application performance monitoring was a nice-to-have. Engineering teams shipped to production, watched their server logs, and hoped for the best. Monitoring was a dashboard someone checked after an outage. APM vendors existed, but adoption was concentrated in the largest enterprises with the biggest budgets and the most painful incidents. By 2015, the conversation had completely shifted. No serious engineering team shipped without Datadog, New Relic, or Sentry in their stack. APM was not a luxury anymore. It was infrastructure. The shift did not happen because the tools got dramatically better overnight. It happened because the systems they monitored got complex enough that operating without observability became professionally irresponsible. I am watching the same inflection happen right now with AI agent observability. And most teams do not see it yet. The Complexity Threshold APM became mandatory when web applications crossed a complexity threshold. Microservices replaced m