MCP v2 is here: Unified.to now supports the stateless 2026-07-28 revision in production
July 28, 2026
The Unified MCP server is one of the first MCP servers to support the stateless 2026-07-28 Model Context Protocol revision, in production as of July 28, 2026, the day that revision was finalized.
The revision removes protocol-level sessions, which will allow an MCP server to run on standard HTTP infrastructure instead of custom session-aware handling at every hop. MCP clients built against earlier revisions will continue to work against the Unified MCP server.
What changed in the 2026-07-28 MCP revision?
The protocol core became stateless. The initialize handshake and the protocol-level session are both gone, and every request is now self-contained, carrying its own protocol version, client identity, and capabilities rather than negotiating them once and relying on the server to remember.
MCP lead maintainers David Soria Parra and Den Delimarsky set out the change in the 2026-07-28 release candidate announcement of May 21, 2026. The specification is in the Model Context Protocol specification repository.
| Before 2026-07-28 | 2026-07-28 | |
|---|---|---|
| Session | Established by an initialize handshake, torn down at close | None |
| Protocol version and capabilities | Negotiated once, then remembered | Sent with every request |
| Server state between calls | Required | None |
| Load balancing | Session affinity or a shared session store | Round-robin, no affinity |
| Gateway routing | Request body inspection | HTTP headers |
| Routing information now also travels in HTTP headers, so networking equipment can route an MCP request without tracking session status or reading the JSON-RPC body. Three features are deprecated: roots, sampling, and logging. Under the specification's feature lifecycle policy, every feature moves through Active, Deprecated, and Removed states, with at least twelve months between deprecation and earliest removal. |
Why does a stateless MCP matter in production?
Because the session was the reason MCP needed special handling everywhere it went. A stateful protocol requires the server to remember a client between calls, which at any real deployment size means sticky load balancer routing, a shared session store, and gateways that inspect request bodies to work out where a call belongs.
That is not how the rest of the internet works, which is why MCP was frequently unusable from inside a corporate network. The request never left the building.
"The important part isn't that it's more efficient. It's that MCP now works with the vast majority of internet infrastructure. HTTP is stateless, so the network hardware that already handles stateless HTTP can now handle MCP."
Roy Pereira, CEO and co-founder, Unified.to
Stateless removes the requirement. The MCP maintainers describe the result as scaling behind a simple round-robin load balancer, with no sticky sessions and no shared session store. A request crosses a gateway on the same terms as any other HTTP call.
What does the Unified MCP server implement?
The stateless protocol core. The 2026-07-28 revision also introduces an extensions framework, MCP Apps for server-rendered interfaces, a Tasks extension for long-running operations, and authorization changes aligned to OAuth and OpenID Connect. The Unified MCP server does not implement these, because none are required for authorized agent access to an end-customer's integration data.
What security controls does the Unified MCP server add?
Data region selection and PII filtering, neither of which the MCP specification defines. Data region selection determines where a connection's data is read from: requests to the EU host are served from Unified's EU data region, and requests to the US host from the US region. hide_sensitive removes PII from tool responses before they reach the model, covering fields including names, emails, and telephone numbers. Both are set per connection.
Authorization on the Unified MCP server is handled by workspace API keys and connection-scoped signed tokens, documented in the MCP authentication reference.
What does this mean for a catalogue of 43,456 tools?
The Unified MCP server carries the largest tool catalogue of any MCP server available: 43,456 tools as of July 22, 2026, including 8,242 unified tools, up from 27,825 and 7,609 on June 30, 2026. Those tools span 575 integrations across 32 categories. The 2026-07-28 revision is what makes that catalogue reachable from where agents actually run. Inside a company network, reachability was the binding constraint rather than integration coverage.
Selection is a separate problem. Current LLM APIs accept a small fraction of a catalogue this size in a single call, so permissions, tools, and defer_tools are what make it usable. The 2026-07-28 revision solves reachability, not selection.
Which endpoint should I use?
Point your MCP client at the streamable HTTP endpoint for your region: https://mcp-api.unified.to/mcp for the US, https://mcp-api-eu.unified.to/mcp for the EU. SSE endpoints exist at /sse on both hosts, but SSE has been deprecated in the MCP protocol.
FAQ
Does Unified.to support the 2026-07-28 MCP specification? Yes. The Unified MCP server supports the stateless protocol core of the 2026-07-28 revision in production as of July 28, 2026, the date that revision was finalized.
What is the 2026-07-28 MCP revision? It is the largest revision of the Model Context Protocol since launch. It makes the protocol core stateless by removing the initialize handshake and protocol-level sessions, and adds routable headers, an extensions framework, and a formal deprecation policy.
Is MCP v2 the same as the 2026-07-28 revision? Yes. MCP v2 is the common name for the 2026-07-28 revision, which is how the specification is formally versioned. The v2 label comes from the major version of the MCP SDKs that support it.
Does the Unified MCP server support MCP Apps or the Tasks extension? No. The Unified MCP server implements the stateless protocol core. MCP Apps and Tasks are not required for authorized agent access to integration data.
Why could MCP not run behind a corporate gateway before? MCP required a protocol-level session, and gateways and firewalls are built for stateless HTTP request-response. Traffic that depended on a persistent session did not survive that path.
Does the stateless revision break my existing MCP client? No. Clients on earlier revisions continue to work against the Unified MCP server, and the specification defines a fallback in the other direction.
How many tools does the Unified MCP server have? 43,456 as of July 22, 2026, including 8,242 unified tools, across 575 integrations in 32 categories. The catalogue changes as integrations and endpoints are added, so check the MCP changelog for the current figure.
Related: how the Unified MCP server works, Composio vs Unified, Unified MCP vs Merge Agent Handler, and Unified MCP vs Arcade.dev.
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Author
Written for Unified.to by Mallory Greene
About the author: Mallory Greene is a writer specializing in generative engine optimization (GEO) and content, through her practice Search Everywhere. She covers integration infrastructure and technical content across Unified.to's technical content library. Based in Toronto.