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What if you don't need MCP at all?

mariozechner.at

61–70 of 194 posts

Re: What if you don't need MCP at all?

#61
post #14

Yeah, "MCP" felt like BS from jump. Basically it's the problem that will always be a problem, namely "AI stuff is non-deterministic." If there was some certainty MCP could add to this equation that would perhaps be theoretically nice, but otherwise it's just .. parsing, a perhaps not "solved" problem, but one for which there's already ample solutions.

Why are they nondeterministic? You can use a fixed seed or temperature=0.

Even with zero temperature (and some of the latest models don’t allow that) you’re still not absolutely guaranteed deterministic output.

Re: What if you don't need MCP at all?

#62

I can see where Mario is coming from, but IMO MCP still has a place because it 1) solves authentication+discoverability, 2) doesn't require code execution. MCP shines when you want to add external functionality to an agent quickly, and in situations where it's not practical to let an agent go wild with code execution and network access. Feels like we're in the "backlash to the early hype" part of the hype cycle. MCP…

Oh, I didn't intend this to come across as MCP being useless. I've written this from the perspective of someone who uses LLMs mostly for coding/computer tasks, where I found MCP to be less than ideal for my use cases.

I actually think MCP can be a multiplier for non-technical users, where it not for some nits like being a bit too technical and the various security footguns many MCP servers hand you.

Re: What if you don't need MCP at all?

#63

MCP was a really shitty attempt at building a plugin framework that was vague enough to lure people into and then allow other companies to build plugin platforms to take care of the MCP non-sense. "What is MCP, what does it bring to the table? Who knows. What does it do? The LLM stuff! Pay us $10 a month thanks!" LLM's have function / tool calling built into them. No major models have any direct knowledge of MCP. Not…

Yeah there's no there there when it comes to MCP. It's crazy to me that the world bought into the idea when the "spec" literally boils down to "have your server give the LLM some json". Just illustrates how powerful it is to attach names to things, especially in a hypestorm in which everyone is already frothing at the mouth and reason is hard to come by. Give people some word they can utter to help them sound like they're on the "bleeding edge" and they'll buy into it even if it's totally pointless.

Re: What if you don't need MCP at all?

#64

[flagged]

MCP is something that's filled with buzzwords and seems like something created solely so that you can be "sold" something. From what I actually gathered, it's basically somehow four things rolled into one:

* A communication protocol, json-rpc esque except it can be done over stdio or via HTTP

* A discovery protocol, like Swagger, to document the "tools" that an endpoint exposes and how it should be used

* A tool calling convention, the specific sequence of tokens the LLM needs to output for something to be recognized as a tool call

* A thin glue layer orchestrating all of the above: injecting the list of available tools into the LLM context, parsing LLM output to detect tool calls and invoke them with appropriate args, and inject results back into LLM context

Re: What if you don't need MCP at all?

#65

I like MCP for _remote_ services such as Linear, Notion, or Sentry. I authenticate once and Claude has the relevant access to access the remote data. Same goes for my team by committing the config. Can I “just call the API”? Yeah, but that takes extra work, and my goal is to reduce extra work.

This is the key. MCP encapsulates tools, auth, instructions.

We always need something for that - and it needs to work for non tech users too

Re: What if you don't need MCP at all?

#67
Hey we actually just released rtrvr.ai, our AI Web Agent Chrome Extension, as a Remote MCP Server that obviates lot of the setup you needed to do. We had the same intuition that the easiest way to scrape is through your own browser and so we expose dedicated MCP tools to do actions, scrape pages, and execute arbitrary code in Chrome's built in sandbox.

We give a copy/pasteable MCP url that you can use with your favorite agent/chatbot/site and give those providers browser context and allow them to do browser actions.

So compared to Playwright MCP and others that require you to run npx and can only be connected to local clients, with ours you just paste a url and can use with any client.

Checkout our recent posts: https://news.ycombinator.com/item?id=45898043 https://www.youtube.com/watch?v=B4BTWNTuE-s

Re: What if you don't need MCP at all?

#68

[flagged]

Yeah, and just like the web space there will be a plethora of different frameworks out there all solving the same problems in their own slightly different, uniquely crappy ways and an entire pointless industry built around ceaselessly creating and rehashing and debating this needlessly bloated ecosystem of competing solutions will emerge and employ many "ai engineers".

Outside of a few notable exceptions, the software industry has become such a joke.

Re: What if you don't need MCP at all?

#69
MCP is how you wrap/distribute/compose things related to tool-use. Tool-use is how you insist on an IO schema that LLMs must conform to. Schemas are how you combat hallucination, and how you can use AI in structured ways for things that it wasn't explicitly trained on. And this is really just scratching the surface of what MCP is for.

You can throw all that away by rejecting MCP completely or by boiling tool-use down to just generating and running unstructured shell commands. But setting aside security issues or why you'd want to embrace more opportunities for hallucination instead of less.. shelling out for everything is perfect faith in the model's ability to generate correct bash for an infinite space of CLI surfaces. You've lost the ability to ever pivot to smaller/cheaper/local models, and now you're more addicted to external vendors/SOTA models.

Consider the following workflow with a large CLI surface that's a candidate for a dedicated LLM tool, maybe ffmpeg. Convert the man page to a JSON schema. Convert the JSON schema to a tool. Add the tool to a MCP server, alongside similar wizards for imagemagick/blender. The first steps can use SOTA models if necessary, but the later steps can all feasibly work for free, as a stand-alone app that has no cloud footprint and no subscription fee. This still works if ffmpeg/blender/imagemagick were private custom tools instead of well-known tools that are decades old. You can test the tools in offline isolation too. And since things like fastmcp support server composition you can push and pop that particular stack of wizards in or out of LLM capabilities.

Good luck getting real composition with markdown files and tweaking prompts for tone by adding a "Please" preamble. Good luck engineering real systems with vague beliefs about magic, no concrete specifications for any part of any step, constantly changing external dependencies, and perfect faith in vendors.

Re: What if you don't need MCP at all?

#70

[flagged]

MCP is something that's filled with buzzwords and seems like something created solely so that you can be "sold" something. From what I actually gathered, it's basically somehow four things rolled into one: * A communication protocol, json-rpc esque except it can be done over stdio or via HTTP * A discovery protocol, like Swagger, to document the "tools" that an endpoint exposes and how it should be used * A tool call…

> * A thin glue layer orchestrating all of the above: injecting the list of available tools into the LLM context, parsing LLM output to detect tool calls and invoke them with appropriate args, and inject results back into LLM context

Yeah llm rules. You think there must be something more to it. There's not.

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