You don't need MCP. You need Claude Skills.
Actually you just need a prompt and some tools
Skills are basically just a prompt and (optionally) some tools, only with a preamble that means they are selectively brought into context only as needed.
What if you don't need MCP at all?
51–60 of 194 posts
Re: What if you don't need MCP at all?
#52So far I have seen two genuinely good arguments for the use of MCPs: * They can encapsulate (API) credentials, keeping those out of reach of the model, * Contrary to APIs, they can change their interface whenever they want and with little consequences.
> * Contrary to APIs, they can change their interface whenever they want and with little consequences.
I already made this argument before, but that's not entirely right. I understand that this is how everybody is doing it right now, but that in itself cause issues for more advanced harnesses. I have one that exposes MCP tools as function calls in code, and it encourages the agent to materialize composed MCP calls into scripts on the file system.
If the MCP server decides to change the tools, those scripts break. That is is also similar issue for stuff like Vercel is advocating for [1].
[1]: https://vercel.com/blog/generate-static-ai-sdk-tools-from-mc...
Re: What if you don't need MCP at all?
#53You don’t need formal tools. You only need a bash tool that can run shell scripts and cli tools! Overwhelmed by Sentry errors recently I remembered sentry-cli. I asked the agent to use it to query for unresolved Sentry errors and make a plan that addresses all of them at once. Zeroed out my Sentry inbox in one Claude Code plan. All up it took about an hour. The agent was capable of sussing out sentry-cli, even runnin…
To add to this, agents view the world through sort of a "choose your own adventure" lens. You want your help output to basically "prompt" the agent, and provide it a curated set of options for next steps (ideally between 4-8 choices). If your CLI has more options than that, you want to break as much as possible into commands. The goal is to create an "decision tree" for the agent to follow based on CLI output.
Re: What if you don't need MCP at all?
#54Earlier quoted context omitted.
MCP defines the API so vendors of LLM tools like cursor, claude code, codex etc don't all make their own bespoke, custom ways to call tools. The main issue is the disagreement on how to declare the MCP tool exists . Cursor, vscode, claude all use basically the same mcp.json file, but then codex uses `config.toml`. There's very little uniformity in project-specific MCP tools as well, they tend to be defined globally.
Maybe this is a dumb question, but isn't this solved by publishing good API docs, and then pointing the LLM to those docs as a training resource?
It is. Anthropic builds stuff like MCP and skills to try and lock people into their ecosystem. I'm sure they were surprised when MCP totally took off (I know I was).
Re: What if you don't need MCP at all?
#55So I don't disagree with any of the criticisms of MCPs but no one here has mentioned why they are useful, and I'm not sure that everyone is aware that MCP is actually just a wrapper over existing cli/API: 1. Claude Code is aware of what MCPs it has access to at all times. 2. Adding an MCP is like adding to the agent's actuators/vocabulary/tools because unlike cli tools or APIs you don't have to constantly remind it w…
1.) Awareness doesn’t mean they will use it. And in practice they often don’t use them. 2.) “ unlike cli tools or APIs you don't have to constantly remind it what MCPs it has available” - this doesn’t match my experience. In fact, bash commands are substantially more discoverable. 3.) Again, this doesn’t match my experience and the major providers recommend including available MCP tools in system prompts/CLAUDE.md/wh…
Chrome Devtools is similarly an extremely high value MCP for me.
I would agree that if you don't find they add discoverability then MCPs would have no value for you and be worse than cli tools. It sounds like we have had very opposite experiences here.
Re: What if you don't need MCP at all?
#56I have a feeling that MCP is going the way GraphQL is going ...
As abstruse as GraphQL is, it does have legitimate use cases. I say this as someone who avoided it for a long time for aesthetic reasons. MCP on the other hand is all hype.
Re: What if you don't need MCP at all?
#57Earlier quoted context omitted.
MCP defines the API so vendors of LLM tools like cursor, claude code, codex etc don't all make their own bespoke, custom ways to call tools. The main issue is the disagreement on how to declare the MCP tool exists . Cursor, vscode, claude all use basically the same mcp.json file, but then codex uses `config.toml`. There's very little uniformity in project-specific MCP tools as well, they tend to be defined globally.
Maybe this is a dumb question, but isn't this solved by publishing good API docs, and then pointing the LLM to those docs as a training resource?
>but isn't this solved by publishing good API docs, and then pointing the LLM to those docs as a training resource?
Yes.
It's not a dumb question. The situation is so dumb you feel like an idiot for asking the obvious question. But it's the right question to ask.
Also you don't need to "train" the LLM on those resources. All major models have function / tool calling built in. Either create your own readme.txt with extra context or, if it's possible, update the API's with more "descriptive" metadata (aka something like swagger) to help the LLM understand how to use the API.
Re: What if you don't need MCP at all?
#58You don't need MCP. You need Claude Skills.
Claude Skills are just good documentation wrapped into Anthropic's API in a proprietary way that's designed to foster lock-in.
Re: What if you don't need MCP at all?
#59Yeah, "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.
The whole point of "agentic AI" is that you don't have to rigorously test every potential interaction, which means that even a temperature zero model may behave unexpectedly, which is bad for security.
Re: What if you don't need MCP at all?
#60So I don't disagree with any of the criticisms of MCPs but no one here has mentioned why they are useful, and I'm not sure that everyone is aware that MCP is actually just a wrapper over existing cli/API: 1. Claude Code is aware of what MCPs it has access to at all times. 2. Adding an MCP is like adding to the agent's actuators/vocabulary/tools because unlike cli tools or APIs you don't have to constantly remind it w…
Also not disagreeing with your argument. Just want to point out that you can achieve the same by putting minimal info about your CLI tools in your global or project specific CLAUDE.md.
The only downside here is that it's more work than `claude mcp add x -- npx x@latest`. But you get composability in return, as well as the intermediate tool outputs not having to pass through the model's context.