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MCP: An (Accidentally) Universal Plugin System

worksonmymachine.substack.com

131–140 of 366 posts

Re: MCP: An (Accidentally) Universal Plugin System

#131

Where do I get started with MCP? I’m all in, but kinda…confused? A REST API makes sense to me…but this is apparently significantly different and more useful. What’s the best way to think about MCP compared to a traditional API? Where do I get started building one? Are there good examples to look at?

Start by reading the documentation - https://modelcontextprotocol.io/introduction

Then use FastMCP to write an MCP server in Python - https://github.com/jlowin/fastmcp

Finally, hook it up to an LLM client. It’s dead simple to do in Claude Code, create an .mcp.json file and define the server’s startup command.

Re: MCP: An (Accidentally) Universal Plugin System

#132
post #101
post #83

Earlier quoted context omitted.

Probably my judgement is a bit fogged. But if I get asked about building AI into our apps just one more time I am absolutely going to drop my job and switch careers

That's likely because OG devs have been seeing the hallucination stuff, unpredicability etc. and questioning how that fits with their carefully curated perfect system What blocked me initially was watching NDA'd demos a year or two back from a couple of big software vendors on how Agents were going to transform enterprise ... what they were showing was a complete non-starter to anyone who had worked in a corporate be…

> That's likely because OG devs have been seeing the hallucination stuff, unpredicability etc. and questioning how that fits with their carefully curated perfect system

That is the odd part. I am far from being part of that group of people. I‘m only 25, I joined the industry in 2018 as part of an training program in a large enterprise.

The odd part is, many of the promises are a bit Déjà-vu even for me. „Agents going to transform the enterprise“ and other promises do not seem that far off the promises that were made during the low code hype cycle.

Cynically, the more I look at the AI projects as an outsider, the more I think AI could fail in enterprises largely because of the same reason low code did. Organizations are made of people and people are messy, as a result the data is often equally messy.

Re: MCP: An (Accidentally) Universal Plugin System

#133
post #121
post #62

Earlier quoted context omitted.

HATEOAS was supposed to be that. https://en.wikipedia.org/wiki/HATEOAS

Wait was it? HATEOAS is all about hypermedia, which means there must be a human in the loop being presented the rendered hypermedia. MCP seems like it's meant to be for machine machine communication, not human machine

My understanding was that the discoverable part of HATEAOS was meant for machine to machine. Actually all of REST is machine to machine except in very trivial situations.

Not sure I'm understanding your point in hypermedia means there is human in the loop. Can you expand?

Re: MCP: An (Accidentally) Universal Plugin System

#134
post #49
post #22

I agree with the article, and I love how the author is (mis-)using MCP. I just want to rephrase what the accident actually is. The accident isn't that somehow we got a protocol to do things we couldn't do before. As other comments point out MCP (the specificaiton), isn't anything new or interesting. No, the accident is that the AI Agent wave made interoperability hype, and vendor lock-in old-fashioned. I don't know h…

How ironic given the amount of APIs that were locking down access in response to AI training! Though the general API lockdown was started long before that, and like you, I’m skeptical that this new wave of open access will last if the promise doesn’t live up to the hype.

i don't think it's ironic at all. the AI boom exposed the value of data. there's two inevitable consequences when the value of something goes up: the people who were previously giving it away for free start charging for it, and the people who weren't previously selling it at all start selling it.

the APIs that used to be free and now aren't were just slightly ahead of the game, all these new MCP servers aren't going to be free either.

Re: MCP: An (Accidentally) Universal Plugin System

#135
post #101
post #83

Earlier quoted context omitted.

Probably my judgement is a bit fogged. But if I get asked about building AI into our apps just one more time I am absolutely going to drop my job and switch careers

That's likely because OG devs have been seeing the hallucination stuff, unpredicability etc. and questioning how that fits with their carefully curated perfect system What blocked me initially was watching NDA'd demos a year or two back from a couple of big software vendors on how Agents were going to transform enterprise ... what they were showing was a complete non-starter to anyone who had worked in a corporate be…

How does MCP solve any of the problems you mentioned? The LLM still has to access your data, still doesn't know the difference between instructions and data, and still gives you hallucinated nonsense back – unless there's some truly magical component to this protocol that I'm missing.

Re: MCP: An (Accidentally) Universal Plugin System

#136

Earlier quoted context omitted.

> Want spell check? MCP server. > Want it to order coffee when you complete 10 tasks? MCP server. With a trip through an LLM for each trivial request? A paid trip? With high overhead and costs?

the whole point of the article is that it doesn't need to be an LLM, MCP is just a standard way to expose tools to things that use tools. LLMs can use tools, but so can humans.

So the whole point of the article is that an API is an API and anything can call an API?

Re: MCP: An (Accidentally) Universal Plugin System

#139
post #4

I don’t want to undermine the author’s enthusiasm for the universality of the MCP. But part of me can’t help wondering: isn’t this the idea of APIs in general? Replace MCP with REST and does that really change anything in the article? Or even an Operating System API? POSIX, anyone? Programs? Unix pipes? Yes, MCP is far simpler/universal than any of those things ended up being — but maybe the solution is to build simp…

MCP is not REST. In your comparison, its more that MCP is a protocol for discovering REST endpoints at runtime and letting users configure what REST endpoints should be used at runtime. Say i'm building a app and I want my users to be able to play spotify songs. Yea, i'll hit the spotify api. But now, say i've launched my app, and I want my users to be able to play a song from sonofm when they hit play. Alright, now…

MCP is a JSON RPC implementation of OpenAPI, or, get this, XML and WSDL/SOAP.

Re: MCP: An (Accidentally) Universal Plugin System

#140
post #22

I agree with the article, and I love how the author is (mis-)using MCP. I just want to rephrase what the accident actually is. The accident isn't that somehow we got a protocol to do things we couldn't do before. As other comments point out MCP (the specificaiton), isn't anything new or interesting. No, the accident is that the AI Agent wave made interoperability hype, and vendor lock-in old-fashioned. I don't know h…

> made interoperability hype, and vendor lock-in old-fashioned

I always imagined software could be written with a core that does the work and the UI would be interchangeable. I like that the current LLM hype is causing it to happen.

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