- CLI tools don't have standardized auth, nor do they have granular tool permissions. MCP does
- CLI tools need to access your secrets in your .env. With MCP the model never sees the secrets and refresh tokens.
- CLI tools don't have auditing and telemetry. MCP provides all this for free.
- CLI tools imply full bash access, a nightmare in terms of security and very costly if you have to spin up a machine for every request for billions of users.
- etc
I'm not especially a fan of MCP but it also offers:
- Standardized input and output schemas for each tool
- Standardized annotations that indicate how potentially dangerous each tool can be (e.g. read-only, idempotent, publishes data visible to third parties)
- Extensions for UI widgets
> CLI tools don’t have standardized auth
EPERM, POSIX ACLs and execute bits.
> CLI tools need to access your secrets in your .env
They can access whichever secret store you want. There are dozens of projects offering valid solutions nowadays for the local tool call space, and they’re equally useful in this scenario.
> CLI tools don’t have auditing and telemetry
They’ve had it for much longer than MCP.
> A nightmare in terms of security
We know how to secure shells. Git over SSH is a hardened, public shell that works all the way up to GitHub scale. You just offer a limited toolset. No escape, unless there’s a vulnerability, which is just as likely with MCP.
> Very costly
It’s a rounding error in comparison to token costs.
None of this is true. The point of "just CLI" is that LLMs are infinitely more trained on working CLI tools. There doesn't need to be real CLI tools behind the harness, as long as the interface is CLI-like.
Show me then how to convert my MCP, including auth, behind a CLI like interface. I don’t think that’s even possible.
"claude -p"
All of the main agent CLI's provides a demonstration that it is possible because they're all callable as a CLI. Several of them, like Codex, Kimi CLI, Pi, OpenCode are open source and so you could obviously strip out the MCP host and client from them and turn them into a CLI. Doing so in a way that keeps auth outside the agents sandbox is trickier and you might end up with a proxy which partly defeats the point but at least still keeps the composability of a CLI.
Can you link it?
Can you elaborate on the auditing and telemetry. I'm wondering what you mean by that and how it comes for free any differently from an cli