Why? MCP and CLI is similar here.

You need agent to find MCP and what it can be used for (context), similarly you can write what CLI use for e.g. jira.

Rest is up to agent, it needs to list what it can do in MCP, similarly CLI with proper help text will list that.

Regarding context those tools are exactly the same.

This feels right in theory and wrong in practice

When measuring speed running blue team CTFs ("Breaking BOTS" talk at Chaos Congress), I saw about a ~2x difference in speed (~= tokens) for a database usage between curl (~skills) vs mcp (~python). In theory you can rewrite the mcp into the skill as .md/.py, but at that point ... .

Also I think some people are talking past one another in these discussions. The skill format is a folder that supports dropping in code files, so much of what MCP does can be copy-pasted into that. However, many people discussing skills mean markdown-only and letting the LLM do the rest, which would require a fancy bootstrapping period to make as smooth as the code version. I'd agree that skills, when a folder coming with code, does feel like largely obviating MCPs for solo use cases, until you consider remote MCPs & OAuth, which seem unaddressed and core in practice for wider use.