The Costs of MCPs

Model Context Protocols (MCPs) are often introduced as a kind of architectural panacea. They promise standardization, portability, and long-term scalability. And while those promises are real, they carry costs that are easy to ignore until you are deep in implementation.

This lab looks squarely at those costs—explicit and hidden—so that choosing MCPs is a decision made with eyes open, not just with hope for elegance.

1. Up-Front Complexity

MCPs require design work before they deliver value.

• Defining schemas: agreeing on what constitutes an Entity, Signal, Event.
• Writing adapters: every integration must now conform to the schema.
• Testing contracts: you must validate not just functionality, but compliance.

For teams in rapid iteration mode, this feels like brakes on momentum. Time spent on schema debates is time not spent showing customers features.

2. Maintenance Overhead

Protocols age. Integrations drift. Every schema decision you make today becomes a governance issue tomorrow.

• Updating a field name means versioning, deprecations, and migration scripts.
• Every new data source tests the boundaries of your protocol; exceptions pile up.
• Tooling must be built (or borrowed) to lint, validate, and enforce compliance.

Without steady maintenance, MCPs rot—and rotting protocols are worse than none at all.

3. Opportunity Cost

Every abstraction you build too early is an abstraction you might regret.

• If the domain is not yet stable, MCPs lock in assumptions that may not hold.
• If the team is small, MCP adoption may crowd out features that win customers.
• By chasing “what could be,” you may weaken “what works now.”

Opportunity cost is often invisible, but it can be the most damaging cost of all.

4. Cognitive Load

MCPs demand that everyone—developers, operators, sometimes even customers—think in terms of the protocol.

• New hires must learn the schema before they can contribute.
• Debugging requires tracing not just the data, but the adapter mapping.
• AI agents themselves need prompt logic tuned to MCP structures.

In exchange for predictability, you raise the bar of entry. That’s fine for enterprise teams, less fine for scrappy startups.

5. Latency and Performance

Abstraction adds steps. Each time data is lifted into an MCP schema, transformed, and passed on, it incurs latency.

In practice the costs may be measured in milliseconds, but for real-time or high-volume systems, the overhead can add up. Sometimes the fastest system is the one that avoids unnecessary protocol layers.

6. Political and Organizational Cost

This one is rarely named: standardization requires agreement.

• Teams must align on field definitions.
• Stakeholders will debate scope creep endlessly.
• Once an MCP is “official,” change requests get political.

The human cost of alignment can rival the technical cost of implementation.

A Balanced View

MCPs are not “free structure.” They are structure purchased at the price of flexibility, speed, and simplicity. In the right context—multi-agent orchestration at scale—the purchase is wise. In the wrong context—an MVP sprint—the same purchase feels like a luxury you can’t afford.

Closing Thought

Every protocol carries a price tag. The question isn’t whether MCPs cost you something—they do. The real question is whether their costs buy you leverage, or whether they only buy you delay.

MCPs are worth it when the cost of not having them exceeds the cost of building them. Until then, consider whether duct tape will hold.