Is MCP dead now that we have Agent Skills?
Over the last few months I’ve seen an increasing number of posts on LinkedIn heralding the death of MCP and the coming reign of Agent Skills. The same posts have replies piled on in violent agreement but claiming that in fact skills are not their death, but it’s command-line interfaces instead. They up-vote each other, repeat each other, and were likely all drafted by AI anyway.
I like to pause and think critically before proclaiming anything dead. In fact almost nothing truly dies in tech. It just continues alongside other new things. If they truly replace all of the benefits, and come with none of the downsides, their adoption makes the other obsolete, but I’m sure there will still be someone happy enough to continue with whatever it might be.
In this case, I cannot agree with the assertion at all. It also isn’t even a fight between the two – as I need and use both. I still create and use MCP servers, and I still create and use Agent Skills.
Myth #1: MCP servers have been replaced by Agent Skills
These are not mutually exclusive, and are often complementary.
- MCP servers provide tools
- Skills provide expertise (sometimes in using those tools) by combining:
- Prompts/instructions
- Scripts
- Reference content
It’s an interesting thought experiment when giving agents capabilities to go through a process that looks something like this:
- Identify a
taskthat I want the agent to do - Ask myself: If the only ability I had was to type or say words, what would I immediately ask for in order to be able to do a given task
- What specific tools?
- What specific knowledge that I don’t already have?
- Ask an AI agent: Given these tools and this knowledge what would you need to complete
task?- Any other tools/information?
- Ask an AI agent, given all of this, what is the process that you would go through to complete the task?
- What parts of that are deterministic?
- Of those, which parts of that are re-usable or generalizable across all tasks?
- What parts of that benefit from more probabilistic behavior, or would typically involve a human making a judgment call?
- What parts of that are deterministic?
After that, you have the ingredients you need to build:
- The tools are MCP servers that might already exists, or become candidates for new MCP servers that will be referenced within an Agent Skill.
- The deterministic, reusable behaviors become candidates for new MCP servers that will be referenced in an Agent Skill.
- The probabilistic behaviors become candidates for prompts within an Agent Skill.
- The deterministic, non-reusable behaviors become scripts within an Agent Skill.
Giving AI my job
For example, if I were to consider a task that has often been a part of my job, I might choose authoring technical learning content. It’s a complex task that I now consider an expertise that I have – whether or not I’m any good at it, I will leave up to you, however I’ve at least spent a large portion of my life doing it.
That task sort of breaks down into the following:
- Research
- Synthesize
- Organize
- Stylize
- Deliver
Research requires access to up-to-date technical information. For example, if I were an AI trying to author content on Azure, I might use the Microsoft Learn MCP server which provides semantic search of content in Microsoft’s official product documentation corpus. I might also use the equivalent built-in fetch tool of the harness that I was using at the time.
Synthesizing information from the research is more of a non-deterministic thing, and would require a measure of human taste/judgement if I were a human, but if I were an AI I would do my best reading/following a document that describes what that looks like – no specific tools needed other than being able to read the research wherever it landed.
Organizing information is another one of those things that requires a measure of expertise. In this case, as a human I’ve taken inspiration over the years from Developing Technical Training: A Structured Approach for Developing Classroom and Computer-based Instructional Materials by Ruth C. Clark. I read it, internalized the key ideas, and now think about and DO organization differently as a result. As an Agent Skills author I would extract the most salient bits relative to organization of information (e.g., the classification into facts, concepts, processes, procedures, and principles).
Stylizing the information usually takes the form of turning it into a story. For that I’ve also relied on books as a human to learn about the subject – and I’ve also learned by observation over the years. One of my favorites being The Writers Journey: Mythic Structure for Writers by Christopher Vogler. Again, as an Agent Skills author I might extract the Hero’s Journey Cycle and include that as a reference alongside a procedural description in prompt form of how to construct a narrative that connects to the learner’s life.
Delivering the information might again become a prompt to have the agent author an application with the ability to display or maybe use TTS to speak out loud the learning content.
Myth #2: MCP servers are dead, use command line tools
Agents already excel with well-known tools – git, npm, dotnet work great via command line.
However, MCP shines where training data doesn’t:
- Custom tools need good descriptions - command line tools not well represented in training data cost you turns and context getting the agent up to speed
- Tool descriptions use context, but save more - a few tokens of description replaces rounds of trial-and-error the agent would spend fumbling with unfamiliar CLIs
- MCP tools are easier to govern - enable, disable, and scope individual tools (consistently supported across different harnesses)
Another aspect to consider is that when you are writing an MCP server, you can both compose and encapsulate those operations that you want AI agents to be able to take. You will also have observability of how AI agents specifically are interacting with your system(s) (i.e., they’re working against interfaces expected to have AI on the other end vs. deterministic code and/or a human directly).
Myth #3: We don’t need MCP servers, agents can already call our APIs
That is true, but with similar caveats as the CLI myth.
However, I would then ask: “Given they already know how to interact with databases, why not allow them to query the database(s) your API talks to directly?”
If you have a strong reaction to that question, then I have successfully delivered the experience I have when considering your assertion that we can have agents call our APIs directly 😊
Myth #4: We don’t need MCP servers, training data covers it
We still need MCP servers for information with:
- Recency: the information is more recent than training data
- Frequency: the information is updated frequently
- Supersession: the information is updated in a way that supersedes/contradicts the information before
- Criticality of grounded actions: the information drives actions where errors are unacceptable
We still need MCP servers to take action.
Myth #5: MCP servers are dead because they use too much context
Context is a very real consideration that requires intentional management because the context “cost” is not just financial cost, it’s also:
- Information cost (i.e., due to early compaction)
- Task Adherence/Focus cost (i.e., due to model drift)
However, outside of the system prompt, and the responses streaming back from the tool calls themselves, you have a ton of control:
block-beta
columns 1
SP["System Prompt"]:1
AGENTS["AGENTS.md"]:1
TD["Tool descriptions"]:1
ASL["Agent Skills listing"]:1
YI["Your instructions"]:1
TC["Tool calls"]:1
TR["Tool responses"]:1
style SP fill:#2d1548,stroke:#bc8cff,color:#e6edf3
style AGENTS fill:#132f4c,stroke:#58a6ff,color:#e6edf3
style TD fill:#132f4c,stroke:#58a6ff,color:#e6edf3
style ASL fill:#132f4c,stroke:#58a6ff,color:#e6edf3
style YI fill:#132f4c,stroke:#58a6ff,color:#e6edf3
style TC fill:#132f4c,stroke:#58a6ff,color:#e6edf3
style TR fill:#2d1548,stroke:#bc8cff,color:#e6edf3
You control what is in AGENTS.md that guides agents overall, you control which tools – and as a result – which tool descriptions are injected into the context of each request, you control which skills are exposed to your agent, you control your own instructions and in turn as a result at least influence if not control the tool calls that are made.
Every one of these represents a lever you can pull to eke out token/context optimization.
When this specific pushback comes up for MCP, it is often best to ask: “How am I planning on achieving the same result without including the tool?”
If it is adding an Agent Skill because it “progressively loads” and doesn’t spam the context – that’s great, but it also does potentially use a lot of context + turns + runs slower if we’re not immediately handing off to scripts inside. It also begs another question: “Why not more precisely manage the tools?” or “Why not design an MCP server that uses meta tools with tool calls to discover tools available in certain contexts/domains?”.
MCP tool context bloat sadly is often self-inflicted, and self-solvable with sufficient focus and effort. Shortcutting leads to context + time loss later that is less visible since it’s not on the first turn.
Summary
The rumors of MCP’s death have been greatly exaggerated. Agents still benefit from having tools in the form of MCP server tools, combined with expertise in the form of Agent Skills, and for common, fairly stable, command line utilities they can readily drive those too – provided you live dangerously or already have governance in place to ensure only specific commands are permitted.