New MCP Spec Just Dropped
The big new features: elicitation, structured tool outputs, and auth is finally fixed for real
let’s dive into elicitation!
modelcontextprotocol.io/specificatio...
New MCP Spec Just Dropped
View original threadelicitation gives the server a way to ask the client a question
the most basic example is, e.g. Cursor asking if you want to *Accept* or *Reject* code changes
an elicitation response has a top-level “action” property that can be “accept”, “reject”, or “cancel”
the most basic example is, e.g. Cursor asking if you want to *Accept* or *Reject* code changes
an elicitation response has a top-level “action” property that can be “accept”, “reject”, or “cancel”
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the server can also supply a simplified JSONSchema that describes structured data
so the server can ask the user specific questions, like “what’s your name?”, “what is your SSN?”, or “what is your bank account number?”
very useful things to paste into an AI!
so the server can ask the user specific questions, like “what’s your name?”, “what is your SSN?”, or “what is your bank account number?”
very useful things to paste into an AI!
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with this feature, MCP is dramatically cutting into A2A’s use case
i frequently differentiate “tool that uses an LLM” from “an agent” by saying that an agent can have unstructured dialog with the client
with this, the only unsupported interaction is the “oh wait, i just thought of something”
i frequently differentiate “tool that uses an LLM” from “an agent” by saying that an agent can have unstructured dialog with the client
with this, the only unsupported interaction is the “oh wait, i just thought of something”
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but also, supporting user interaction is hard
people get distracted, meaning that your server might be left hanging for days waiting for a user to get back
now you have to manage state carefully!
i wrote about managing this state in A2A, and the same applies here
timkellogg.me/blog/2025/06...
people get distracted, meaning that your server might be left hanging for days waiting for a user to get back
now you have to manage state carefully!
i wrote about managing this state in A2A, and the same applies here
timkellogg.me/blog/2025/06...
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