You failed to describe what value the MCP protocol provides.
If all of these companies spent equivalent time writing a CLI for agents to consume as they spend on MCP servers, would they be any worse off in terms of agents being able to interact with their products?
Yes, in the same way a programming language would be worse off if they focused all of their effort on building an implementation instead of a language specification.
You could literally, deterministically, zero AI, code-gen a CLI from an MCP specification, just like you can with an OpenAPI specification. I'm sure tools exist that do this. So if you want a CLI, there it is.
But the problem with a CLI is that it requires a shell environment, and not everywhere you may want to run an agent should or can have access to a shell. MCP enables the harness to tightly control that access. MCP allows the user to easily allowlist/denylist specific tools, or categorize tools into "ask me every time" versus "don't ask me just do it". Doing any of this with a CLI is really hard because CLIs are all very different; yes, AIs can easily learn how to use them, but that might be exactly what you don't want, hey AI don't issue that aws ec2 delete-instance command ah crap there it goes I wish I could have just denylisted its access to that tool.
Not a fan of MCPs for my personal use, but I still think the value for companies is obvious. The first value for their downstream (OpenAI, Anthropic, etc) is REST call vs arbitrary code execution. You only need to "trust" the MCP client implementation, not a thousand different CLIs. Also being a standard HTTP endpoint, a lot of logic can be offloaded to proxies and such.
The second value is more about how business works. There is no chance you can convince someone at WalMart to fund and release a `wmctl` that allows you to search and buy products. Now try to convince your regional Pizza chain to release a CLI too. WalMart and such are incentivized however to create "Whatever OpenAI and Anthropic integrate with". Shopify can create an MCP for every shop and allow the shop owner to customize it. Creating a CLI per shop makes no sense. OpenAI and Anthropic prefer MCPs because of the first benefit. So it works out for all parties involved.
The security model and runtime requirements are completely different between making an HTTP request and executing arbitrary code.
They have different tradeoffs.
I have a couple MCP servers connected to my Claude web & mobile clients. How would your clis work there?
Yes they would be.
MCP servers on the side of the consuming organizations fit into the existing IT landscape, with centralized safeguard on who can access what a lot better and are easier to administer than letting their employees run arbitrary agents against arbitrary sources and destinations and cause chaos.
The value is that many companies like building MCP servers much more than CLIs. For whatever reason.
Here's some companies that offer MCP servers but don't seem to offer an equally featured CLI:
- Asana
- Square
- Linear
- Dropbox
- Canva
- Slack (sorta)
- Figma (sorta)
and many more that offer both, but support their MCP more.Should they all be offering CLI tools? IMHO, yes absolutely. But an MCP server gets much more interest. I'd rather encourage them to keep improving and supporting their MCP services than telling them to drop it for a CLI.
There's lots of things like this in technology where you end up stuck with the first thing because its popularity perpetuates itself. The QWERTY keyboard I'm typing this on is a prime example. x86 is another one.
One advantage is the MCP advertises itself to the agent with its schema and api shape. Unless your CLI is in the corpus with lots of examples the agent has to learn every time. Skills help a little bit but I find the recall on skills pretty low. However I also find codex will reliably use MCPs advertised while Claude always reaches for tools like Bash() likely because it’s aligned so heavily on its own tools and is very hard to get to use an MCP if literally any Bash() approach is possible, including breaking glass to find creds, even when an MCP is clearly advertised in CLAUDE.md, skills, and explicit user instruction. I find it fascinating that Anthropic makes a product that seems to be really poor at following instructions and OpenAI seems to generally follow guard rails.