Excellent improvement. The server-side complexity required to handle sessions has been a large burden both on infrastructure and on educating teams on its characteristics.
I'd made the shift to HTTP/Stateless from MCP a few months ago. It's the right thing to do IMHO. Reliability up, problems down. TOON support is natural, if desired, etc.
My only question is how do you handle channels in the architecture now. From what I saw in Claude Code, shifting to a totally http world has some timeout issues if a server drops out and comes back. Because of that I'm stuck writing stubs for my internal use MCP, this is fine for me, but if you are cleaning up semantics: Understanding how we expect clients to act around failure would really help, the story.
This is the right practice. Why put the burden on the server? It is the job of client to remember, not the server. Server is there to serve requests, not do the remembering. That is how http worked from the beginning and that is why it has been successful.
It was clear from the start (to anyone who ever designed a protocol [1]) that MCP was a pile anti-patterns. They are slowly undoing the mistakes one by one. Maybe next years version will finally be something usable that it could have been from v1.
Yes. However, using something like MCP encourages many companies to claim that they are "integrating AI" -- and typical MCP implementations burn tokens quite profitably.
The improvements look great. At the same time I wonder if it is possible to keep using MCP 1.x as well for now. Development is expensive, right? It also looks possible to transition to MCP 2.x by tackling the different improvements one at a time as long as we take stateless core first?
Hey folks - one of the Lead Maintainers for MCP. Happy that we got this release out the door today, this is an exciting change for those that wanted to roll out remove MCP servers into serverless hosts. There is, of course, more good stuff packed, so if you have questions or feedback - our team is here to help!
Any new to share on file upload support? We have shipped a MCP server and it has been really frustrating to observe MCP clients fumbling around with base64-encodings, polluting their context window with binary data. SEP-1306 (Binary Mode Elicitation) was superseded by SEP-2356 (File input support for tools and elicitation), and that was in turned superseded by SEP-2631 (File Objects and Transfer) which is currently left in a draft state with little activity.
Allowing LLM-based agents to shuffle binary data around efficiently and reliably seems like a pretty big gap in the current specification, if you ask me!
What’s the best practice for tools where the upstream API only supports basic auth (username/password) and there’s no OBO option? In my case the login returns a token that’s only valid for an hour, so the user has to re-auth after that. Do you stash the credentials on the MCP server and silently refresh, or is there a nicer pattern people are using?
URL Elicitation works well if a human is driving the client. Unfortunately MCP client support is patchy but I expect that will change now the protocol is stateless.
To be honest I've completely ignored this feature and 95% of my colleagues at work have not interacted with it at all - we are not an AI pilled company - but this specification now seems mature enough for me to be excited about developing a server, just haven't found a concrete use case yet that isn't already publicly available.
Perfect. The actual tool calls are stateless anyway; when an LLM asks get_my_todos and then asks add_todo it’s not actually holding anything in RAM it’s just text going back into the context window (get_my_todos results) and then another tool call
And even on the server side statefulness is very iffy anyway. How long are you going to hold something in RAM from a client and how long will you hold the connection open
Excellent improvement. The server-side complexity required to handle sessions has been a large burden both on infrastructure and on educating teams on its characteristics.
I'd made the shift to HTTP/Stateless from MCP a few months ago. It's the right thing to do IMHO. Reliability up, problems down. TOON support is natural, if desired, etc.
My only question is how do you handle channels in the architecture now. From what I saw in Claude Code, shifting to a totally http world has some timeout issues if a server drops out and comes back. Because of that I'm stuck writing stubs for my internal use MCP, this is fine for me, but if you are cleaning up semantics: Understanding how we expect clients to act around failure would really help, the story.
This is the right practice. Why put the burden on the server? It is the job of client to remember, not the server. Server is there to serve requests, not do the remembering. That is how http worked from the beginning and that is why it has been successful.
It was clear from the start (to anyone who ever designed a protocol [1]) that MCP was a pile anti-patterns. They are slowly undoing the mistakes one by one. Maybe next years version will finally be something usable that it could have been from v1.
[1] https://news.ycombinator.com/item?id=44016783
Yes. However, using something like MCP encourages many companies to claim that they are "integrating AI" -- and typical MCP implementations burn tokens quite profitably.
The improvements look great. At the same time I wonder if it is possible to keep using MCP 1.x as well for now. Development is expensive, right? It also looks possible to transition to MCP 2.x by tackling the different improvements one at a time as long as we take stateless core first?
Hey folks - one of the Lead Maintainers for MCP. Happy that we got this release out the door today, this is an exciting change for those that wanted to roll out remove MCP servers into serverless hosts. There is, of course, more good stuff packed, so if you have questions or feedback - our team is here to help!
Congrats at shipping the new specification!
Any new to share on file upload support? We have shipped a MCP server and it has been really frustrating to observe MCP clients fumbling around with base64-encodings, polluting their context window with binary data. SEP-1306 (Binary Mode Elicitation) was superseded by SEP-2356 (File input support for tools and elicitation), and that was in turned superseded by SEP-2631 (File Objects and Transfer) which is currently left in a draft state with little activity.
Allowing LLM-based agents to shuffle binary data around efficiently and reliably seems like a pretty big gap in the current specification, if you ask me!
Thank you for your work! I was looking forward to the stateless update.
Great work! Any word on when to expect support across claude clients?
We are actively working on this - the support is rolling out across the ecosystem: https://claude.com/blog/bringing-mcp-2026-07-28-to-claude
When will java sdk come out with latest changes from spec?
Thank you!
What’s the best practice for tools where the upstream API only supports basic auth (username/password) and there’s no OBO option? In my case the login returns a token that’s only valid for an hour, so the user has to re-auth after that. Do you stash the credentials on the MCP server and silently refresh, or is there a nicer pattern people are using?
URL Elicitation works well if a human is driving the client. Unfortunately MCP client support is patchy but I expect that will change now the protocol is stateless.
To be honest I've completely ignored this feature and 95% of my colleagues at work have not interacted with it at all - we are not an AI pilled company - but this specification now seems mature enough for me to be excited about developing a server, just haven't found a concrete use case yet that isn't already publicly available.
Perfect. The actual tool calls are stateless anyway; when an LLM asks get_my_todos and then asks add_todo it’s not actually holding anything in RAM it’s just text going back into the context window (get_my_todos results) and then another tool call
And even on the server side statefulness is very iffy anyway. How long are you going to hold something in RAM from a client and how long will you hold the connection open
are they coming up with an alternative? i use them to monitor workflows that takes days and now i have to make some changes
This protocol change doesn't require you to do anything to existing running MCP code - only if you want to take advantage of new capabilities!
Are the HTTP headers for method/name etc even needed at this point and just use urls instead?
e.g. mymcpserver.com/tools/call?mcp-method=search