infochanged

Agents, Workers - Agents SDK adds MCP Specification 2026-07-28 support

Announced: 2026-07-27
Effective: 2026-07-28
Tags: Agents, Workers
Severity: info, set by reef/rss-rule-v1
Source: https://developers.cloudflare.com/changelog/post/2026-07-27-agents-sdk-v0.20.0-mcp-sdk-v2/

Agents SDK v0.20.0 adds client and server support for the <a href="https://blog.modelcontextprotocol.io/posts/2026-07-28-release-candidate/" target="_blank" rel="noopener">MCP 2026-07-28 release candidate ↗︎</a>. Workers can serve tools, prompts, resources, and elicitation without an MCP transport session or Durable Object. Agents can connect to both MCP 2026-07-28 servers and existing legacy servers. <div tabindex="-1" class="heading-wrapper level-h4"><h4 id="client-support">Client support</h4><a class="anchor-link" href="#client-support"><svg width="16" height="16" viewBox="0 0 24 24"><path fill="currentcolor" d="m12.11 15.39-3.88 3.88a2.52 2.52 0 0 1-3.5 0 2.47 2.47 0 0 1 0-3.5l3.88-3.88a1 1 0 0 0-1.42-1.42l-3.88 3.89a4.48 4.48 0 0 0 6.33 6.33l3.89-3.88a1 1 0 1 0-1.42-1.42Zm8.58-12.08a4.49 4.49 0 0 0-6.33 0l-3.89 3.88a1 1 0 0 0 1.42 1.42l3.88-3.88a2.52 2.52 0 0 1 3.5 0 2.47 2.47 0 0 1 0 3.5l-3.88 3.88a1 1 0 1 0 1.42 1.42l3.88-3.89a4.49 4.49 0 0 0 0-6.33ZM8.83 15.17a1 1 0 0 0 1.1.22 1 1 0 0 0 .32-.22l4.92-4.92a1 1 0 0 0-1.42-1.42l-4.92 4.92a1 1 0 0 0 0 1.42Z"></path></svg></a></div> The MCP client manager now uses <code>@modelcontextprotocol/client</code>. For each connection, it probes for MCP 2026-07-28 support with <code>server/discover</code>. If the server does not support the stateless protocol, the client continues with the legacy <code>initialize</code> handshake on the same connection. Existing <code>addMcpServer</code> calls do not need a protocol-version setting or separate clients for each protocol generation. For stateless requests, elicitation uses <code>input_required</code> through multi-round-trip requests (MRTR). The legacy path uses the same form and URL handlers for pushed requests. The SDK collects input, retries the original operation, and resolves the original <code>callTool</code>, <code>getPrompt</code>, or <code>readResource</code> promise with its final result. OAuth callbacks now validate issuer metadata through the v2 SDK. Discovery state and issuer-bound credentials persist across browser redirects and Durable Object hibernation. <div tabindex="-1" class="heading-wrapper level-h4"><h4 id="run-stateless-servers">Run stateless servers</h4><a class="anchor-link" href="#run-stateless-servers"><svg width="16" height="16" viewBox="0 0 24 24"><path fill="currentcolor" d="m12.11 15.39-3.88 3.88a2.52 2.52 0 0 1-3.5 0 2.47 2.47 0 0 1 0-3.5l3.88-3.88a1 1 0 0 0-1.42-1.42l-3.88 3.89a4.48 4.48 0 0 0 6.33 6.33l3.89-3.88a1 1 0 1 0-1.42-1.42Zm8.58-12.08a4.49 4.49 0 0 0-6.33 0l-3.89 3.88a1 1 0 0 0 1.42 1.42l3.88-3.88a2.52 2.52 0 0 1 3.5 0 2.47 2.47 0 0 1 0 3.5l-3.88 3.88a1 1 0 1 0 1.42 1.42l3.88-3.89a4.49 4.49 0 0 0 0-6.33ZM8.83 15.17a1 1 0 0 0 1.1.22 1 1 0 0 0 .32-.22l4.92-4.92a1 1 0 0 0-1.42-1.42l-4.92 4.92a1 1 0 0 0 0 1.42Z"></path></svg></a></div> <code>createMcpHandler</code> now accepts a factory that returns a server from <code>@modelcontextprotocol/server</code>. The factory creates an isolated server for each request. <div><div data-nb-tabs data-nb-sync-key="workersExamples" class><div class="relative flex border-b border-border" role="tablist" data-nb-tabs-list></div><div class="mt-3"><div role="tabpanel" data-nb-tabs-content data-nb-tab-label="JavaScript" class><figure class="nb-code-figure" data-nb-lang="js"><pre class="astro-code astro-code-themes github-light github-dark nb-shiki-c6xiwz" tabindex="0" data-language="js" data-nb-lang="js"><code>import { McpServer } from "@modelcontextprotocol/server"; import { createMcpHandler } from "agents/mcp/server"; function createServer() { return new McpServer({ name: "example", version: "1.0.0" }); } export default { fetch(request, env, ctx) { return createMcpHandler(createServer)(request, env, ctx); }, };</code></pre></figure></div><div role="tabpanel" data-nb-tabs-content data-nb-tab-label="TypeScript" class><figure class="nb-code-figure" data-nb-lang="ts"><pre class="astro-code astro-code-themes github-light github-dark nb-shiki-c6xiwz" tabindex="0" data-language="ts" data-nb-lang="ts"><code>import { McpServer } from "@modelcontextprotocol/server"; import { createMcpHandler } from "agents/mcp/server"; function createServer() { return new McpServer({ name: "example", version: "1.0.0" }); } export default { fetch(request, env, ctx) { return createMcpHandler(createServer)(request, env, ctx); }, } satisfies ExportedHandler;</code></pre></figure></div></div></div><script type="module" src="https://developers.cloudflare.com/home/runner/work/cloudflare-docs/cloudflare-docs/src/components/ui/tabs/Tabs.astro?astro&type=script&index=0&lang.ts"></script></div> The isolated <code>agents/mcp/server</code> entry keeps <code>McpAgent</code>, <code>WorkerTransport</code>, MCP client transports, and SDK v1 modules out of stateless server bundles. The Workers wrapper validates present browser Origins, supports explicit delegation to trusted Origin middleware, and exposes request handling plus typed change notifications. <div tabindex="-1" class="heading-wrapper level-h4"><h4 id="backward-compatibility">Backward compatibility</h4><a class="anchor-link" href="#backward-compatibility"><svg width="16" height="16" viewBox="0 0 24 24"><path fill="currentcolor" d="m12.11 15.39-3.88 3.88a2.52 2.52 0 0 1-3.5 0 2.47 2.47 0 0 1 0-3.5l3.88-3.88a1 1 0 0 0-1.42-1.42l-3.88 3.89a4.48 4.48 0 0 0 6.33 6.33l3.89-3.88a1 1 0 1 0-1.42-1.42Zm8.58-12.08a4.49 4.49 0 0 0-6.33 0l-3.89 3.88a1 1 0 0 0 1.42 1.42l3.88-3.88a2.52 2.52 0 0 1 3.5 0 2.47 2.47 0 0 1 0 3.5l-3.88 3.88a1 1 0 1 0 1.42 1.42l3.88-3.89a4.49 4.49 0 0 0 0-6.33ZM8.83 15.17a1 1 0 0 0 1.1.22 1 1 0 0 0 .32-.22l4.92-4.92a1 1 0 0 0-1.42-1.42l-4.92 4.92a1 1 0 0 0 0 1.42Z"></path></svg></a></div> The same <code>createMcpHandler(createServer)(request, env, ctx)</code> route serves MCP 2026-07-28 clients and legacy clients that use stateless requests. You do not need separate routes or tool definitions for ordinary tools, prompts, and resources. <code>McpAgent</code> is deprecated and feature-frozen. Migrate existing <code>McpAgent</code> servers to the stateless handler at your earliest convenience. If a server depends on protocol sessions, RPC, pushed server-to-client requests, standalone streams, or replay, use the <a href="https://developers.cloudflare.com/agents/model-context-protocol/guides/migrate-to-mcp-sdk-v2/">migration guide</a> to design stateless equivalents and run both routes while clients transition. <div tabindex="-1" class="heading-wrapper level-h4"><h4 id="migrate-existing-sdk-v1-servers">Migrate existing SDK v1 servers</h4><a class="anchor-link" href="#migrate-existing-sdk-v1-servers"><svg width="16" height="16" viewBox="0 0 24 24"><path fill="currentcolor" d="m12.11 15.39-3.88 3.88a2.52 2.52 0 0 1-3.5 0 2.47 2.47 0 0 1 0-3.5l3.88-3.88a1 1 0 0 0-1.42-1.42l-3.88 3.89a4.48 4.48 0 0 0 6.33 6.33l3.89-3.88a1 1 0 1 0-1.42-1.42Zm8.58-12.08a4.49 4.49 0 0 0-6.33 0l-3.89 3.88a1 1 0 0 0 1.42 1.42l3.88-3.88a2.52 2.52 0 0 1 3.5 0 2.47 2.47 0 0 1 0 3.5l-3.88 3.88a1 1 0 1 0 1.42 1.42l3.88-3.89a4.49 4.49 0 0 0 0-6.33ZM8.83 15.17a1 1 0 0 0 1.1.22 1 1 0 0 0 .32-.22l4.92-4.92a1 1 0 0 0-1.42-1.42l-4.92 4.92a1 1 0 0 0 0 1.42Z"></path></svg></a></div> Upgrade the Agents SDK: <script> if (!customElements.get("nb-pm-restore")) { customElements.define( "nb-pm-restore", class extends HTMLElement { connectedCallback() { const card = this.closest("[data-nb-pm]"); if (!card) return; let saved; try { saved = sessionStorage.getItem("ui-pm-tab"); } catch { return; } if (!saved) return; const tabs = card.querySelectorAll("[data-nb-pm-tab]"); let idx = -1; tabs.forEach(function (t, i) { if (t.textContent.trim() === saved) idx = i; }); if (idx < 1) return; tabs.forEach(function (t, i) { t.setAttribute("aria-selected", String(i === idx)); }); card.querySelectorAll("[data-nb-pm-panel]").forEach(function (p, i) { p.hidden = i !== idx; }); } }, ); } </script><div data-nb-pm class="w-full"><div class="flex w-full flex-col overflow-hidden rounded-lg text-sm ring ring-border bg-card"><div class="flex items-center gap-2 px-3 py-2 text-[0.8125rem] font-medium leading-5 text-muted-foreground bg-[var(--nb-surface-sunken)]" role="tablist" aria-label="Package manager"><button role="tab" type="button" aria-selected="true" aria-controls="pm-panel-pm-19fe24e6-npm" id="pm-tab-pm-19fe24e6-npm" data-nb-pm-tab class="text-muted-foreground hover:bg-accent hover:text-foreground aria-selected:bg-selected aria-selected:text-foreground focus-visible:outline-ring m-0 cursor-pointer rounded-md border-0 bg-transparent px-2 py-0.5 text-xs leading-5 font-medium transition-colors focus-visible:outline-2 focus-visible:outline-offset-2">npm</button><button role="tab" type="button" aria-selected="false" aria-controls="pm-panel-pm-19fe24e6-yarn" id="pm-tab-pm-19fe24e6-yarn" data-nb-pm-tab class="text-muted-foreground hover:bg-accent hover:text-foreground aria-selected:bg-selected aria-selected:text-foreground focus-visible:outline-ring m-0 cursor-pointer rounded-md border-0 bg-transparent px-2 py-0.5 text-xs leading-5 font-medium transition-colors focus-visible:outline-2 focus-visible:outline-offset-2">yarn</button><button role="tab" type="button" aria-selected="false" aria-controls="pm-panel-pm-19fe24e6-pnpm" id="pm-tab-pm-19fe24e6-pnpm" data-nb-pm-tab class="text-muted-foreground hover:bg-accent hover:text-foreground aria-selected:bg-selected aria-selected:text-foreground focus-visible:outline-ring m-0 cursor-pointer rounded-md border-0 bg-transparent px-2 py-0.5 text-xs leading-5 font-medium transition-colors focus-visible:outline-2 focus-visible:outline-offset-2">pnpm</button><button role="tab" type="button" aria-selected="false" aria-controls="pm-panel-pm-19fe24e6-bun" id="pm-tab-pm-19fe24e6-bun" data-nb-pm-tab class="text-muted-foreground hover:bg-accent hover:text-foreground aria-selected:bg-selected aria-selected:text-foreground focus-visible:outline-ring m-0 cursor-pointer rounded-md border-0 bg-transparent px-2 py-0.5 text-xs leading-5 font-medium transition-colors focus-visible:outline-2 focus-visible:outline-offset-2">bun</button></div><div role="tabpanel" id="pm-panel-pm-19fe24e6-npm" aria-labelledby="pm-tab-pm-19fe24e6-npm" data-nb-pm-panel class="bg-card ring-border relative overflow-hidden rounded-lg text-inherit ring"><div class="flex items-stretch"><pre class="text-foreground my-0 min-w-0 grow overflow-x-auto border-0 bg-transparent px-4 py-3 font-mono text-sm leading-relaxed whitespace-pre"><code data-nb-pm-code>npm i agents@latest</code></pre><button type="button" data-nb-pm-copy data-nb-command="npm i agents@latest" aria-label="Copy to clipboard" class="border-border text-muted-foreground hover:text-foreground focus-visible:outline-ring m-0 flex shrink-0 cursor-pointer items-center justify-center border-0 border-l border-solid bg-transparent px-3 transition-colors focus-visible:outline-2 focus-visible:-outline-offset-2"><svg width="1em" height="1em" viewBox="0 0 256 256" class="h-[18px] w-[18px]" data-icon="ph:copy"><path fill="currentColor" d="M216 32H88a8 8 0 0 0-8 8v40H40a8 8 0 0 0-8 8v128a8 8 0 0 0 8 8h128a8 8 0 0 0 8-8v-40h40a8 8 0 0 0 8-8V40a8 8 0 0 0-8-8m-56 176H48V96h112Zm48-48h-32V88a8 8 0 0 0-8-8H96V48h112Z"/></svg><svg width="1em" height="1em" viewBox="0 0 256 256" class="hidden h-[18px] w-[18px]" data-icon="ph:check"><path fill="currentColor" d="m229.66 77.66l-128 128a8 8 0 0 1-11.32 0l-56-56a8 8 0 0 1 11.32-11.32L96 188.69L218.34 66.34a8 8 0 0 1 11.32 11.32"/></svg></button></div></div><div role="tabpanel" id="pm-panel-pm-19fe24e6-yarn" aria-labelledby="pm-tab-pm-19fe24e6-yarn" hidden data-nb-pm-panel class="bg-card ring-border relative overflow-hidden rounded-lg text-inherit ring"><div class="flex items-stretch"><pre class="text-foreground my-0 min-w-0 grow overflow-x-auto border-0 bg-transparent px-4 py-3 font-mono text-sm leading-relaxed whitespace-pre"><code data-nb-pm-code>yarn add agents@latest</code></pre><button type="button" data-nb-pm-copy data-nb-command="yarn add agents@latest" aria-label="Copy to clipboard" class="border-border text-muted-foreground hover:text-foreground focus-visible:outline-ring m-0 flex shrink-0 cursor-pointer items-center justify-center border-0 border-l border-solid bg-transparent px-3 transition-colors focus-visible:outline-2 focus-visible:-outline-offset-2"><svg width="1em" height="1em" viewBox="0 0 256 256" class="h-[18px] w-[18px]" data-icon="ph:copy"><path fill="currentColor" d="M216 32H88a8 8 0 0 0-8 8v40H40a8 8 0 0 0-8 8v128a8 8 0 0 0 8 8h128a8 8 0 0 0 8-8v-40h40a8 8 0 0 0 8-8V40a8 8 0 0 0-8-8m-56 176H48V96h112Zm48-48h-32V88a8 8 0 0 0-8-8H96V48h112Z"/></svg><svg width="1em" height="1em" viewBox="0 0 256 256" class="hidden h-[18px] w-[18px]" data-icon="ph:check"><path fill="currentColor" d="m229.66 77.66l-128 128a8 8 0 0 1-11.32 0l-56-56a8 8 0 0 1 11.32-11.32L96 188.69L218.34 66.34a8 8 0 0 1 11.32 11.32"/></svg></button></div></div><div role="tabpanel" id="pm-panel-pm-19fe24e6-pnpm" aria-labelledby="pm-tab-pm-19fe24e6-pnpm" hidden data-nb-pm-panel class="bg-card ring-border relative overflow-hidden rounded-lg text-inherit ring"><div class="flex items-stretch"><pre class="text-foreground my-0 min-w-0 grow overflow-x-auto border-0 bg-transparent px-4 py-3 font-mono text-sm leading-relaxed whitespace-pre"><code data-nb-pm-code>pnpm add agents@latest</code></pre><button type="button" data-nb-pm-copy data-nb-command="pnpm add agents@latest" aria-label="Copy to clipboard" class="border-border text-muted-foreground hover:text-foreground focus-visible:outline-ring m-0 flex shrink-0 cursor-pointer items-center justify-center border-0 border-l border-solid bg-transparent px-3 transition-colors focus-visible:outline-2 focus-visible:-outline-offset-2"><svg width="1em" height="1em" viewBox="0 0 256 256" class="h-[18px] w-[18px]" data-icon="ph:copy"><path fill="currentColor" d="M216 32H88a8 8 0 0 0-8 8v40H40a8 8 0 0 0-8 8v128a8 8 0 0 0 8 8h128a8 8 0 0 0 8-8v-40h40a8 8 0 0 0 8-8V40a8 8 0 0 0-8-8m-56 176H48V96h112Zm48-48h-32V88a8 8 0 0 0-8-8H96V48h112Z"/></svg><svg width="1em" height="1em" viewBox="0 0 256 256" class="hidden h-[18px] w-[18px]" data-icon="ph:check"><path fill="currentColor" d="m229.66 77.66l-128 128a8 8 0 0 1-11.32 0l-56-56a8 8 0 0 1 11.32-11.32L96 188.69L218.34 66.34a8 8 0 0 1 11.32 11.32"/></svg></button></div></div><div role="tabpanel" id="pm-panel-pm-19fe24e6-bun" aria-labelledby="pm-tab-pm-19fe24e6-bun" hidden data-nb-pm-panel class="bg-card ring-border relative overflow-hidden rounded-lg text-inherit ring"><div class="flex items-stretch"><pre class="text-foreground my-0 min-w-0 grow overflow-x-auto border-0 bg-transparent px-4 py-3 font-mono text-sm leading-relaxed whitespace-pre"><code data-nb-pm-code>bun add agents@latest</code></pre><button type="button" data-nb-pm-copy data-nb-command="bun add agents@latest" aria-label="Copy to clipboard" class="border-border text-muted-foreground hover:text-foreground focus-visible:outline-ring m-0 flex shrink-0 cursor-pointer items-center justify-center border-0 border-l border-solid bg-transparent px-3 transition-colors focus-visible:outline-2 focus-visible:-outline-offset-2"><svg width="1em" height="1em" viewBox="0 0 256 256" class="h-[18px] w-[18px]" data-icon="ph:copy"><path fill="currentColor" d="M216 32H88a8 8 0 0 0-8 8v40H40a8 8 0 0 0-8 8v128a8 8 0 0 0 8 8h128a8 8 0 0 0 8-8v-40h40a8 8 0 0 0 8-8V40a8 8 0 0 0-8-8m-56 176H48V96h112Zm48-48h-32V88a8 8 0 0 0-8-8H96V48h112Z"/></svg><svg width="1em" height="1em" viewBox="0 0 256 256" class="hidden h-[18px] w-[18px]" data-icon="ph:check"><path fill="currentColor" d="m229.66 77.66l-128 128a8 8 0 0 1-11.32 0l-56-56a8 8 0 0 1 11.32-11.32L96 188.69L218.34 66.34a8 8 0 0 1 11.32 11.32"/></svg></button></div></div><nb-pm-restore style="display:contents"></nb-pm-restore></div></div><script type="module" src="https://developers.cloudflare.com/home/runner/work/cloudflare-docs/cloudflare-docs/src/components/ui/package-managers/PackageManagerTabs.astro?astro&type=script&index=0&lang.ts"></script> Move ordinary SDK v1 server definitions into an SDK v2 factory and serve them with <code>createMcpHandler</code>. The handler's default legacy compatibility means most stateless deployments need only one route. If an existing <code>McpAgent</code> server still needs sessionful features, add the stateless path beside it. Use <code>isLegacyRequest()</code> to send only legacy traffic to the existing route: <div><div data-nb-tabs data-nb-sync-key="workersExamples" class><div class="relative flex border-b border-border" role="tablist" data-nb-tabs-list></div><div class="mt-3"><div role="tabpanel" data-nb-tabs-content data-nb-tab-label="JavaScript" class><figure class="nb-code-figure" data-nb-lang="js"><pre class="astro-code astro-code-themes github-light github-dark nb-shiki-c6xiwz" tabindex="0" data-language="js" data-nb-lang="js"><code>import { isLegacyRequest } from "@modelcontextprotocol/server"; import { createMcpHandler } from "agents/mcp/server"; import { MyMcpAgent } from "./legacy-server"; import { createServer } from "./server"; const stateless = createMcpHandler(createServer, { route: "/mcp", legacy: "reject", }); const legacy = MyMcpAgent.serve("/mcp"); export default { async fetch(request, env, ctx) { if (await isLegacyRequest(request)) { return legacy.fetch(request, env, ctx); } return stateless(request, env, ctx); }, };</code></pre></figure></div><div role="tabpanel" data-nb-tabs-content data-nb-tab-label="TypeScript" class><figure class="nb-code-figure" data-nb-lang="ts"><pre class="astro-code astro-code-themes github-light github-dark nb-shiki-c6xiwz" tabindex="0" data-language="ts" data-nb-lang="ts"><code>import { isLegacyRequest } from "@modelcontextprotocol/server"; import { createMcpHandler } from "agents/mcp/server"; import { MyMcpAgent } from "./legacy-server"; import { createServer } from "./server"; const stateless = createMcpHandler(createServer, { route: "/mcp", legacy: "reject", }); const legacy = MyMcpAgent.serve("/mcp"); export default { async fetch(request: Request, env: Env, ctx: ExecutionContext) { if (await isLegacyRequest(request)) { return legacy.fetch(request, env, ctx); } return stateless(request, env, ctx); }, } satisfies ExportedHandler<Env>;</code></pre></figure></div></div></div></div> Migrate the remaining sessionful features, allow existing sessions to drain, then remove the legacy route. Refer to <a href="https://developers.cloudflare.com/agents/model-context-protocol/guides/migrate-to-mcp-sdk-v2/">Migrate to MCP SDK v2</a> for package changes, compatibility limits, and rollout steps. <div tabindex="-1" class="heading-wrapper level-h4"><h4 id="deprecations-in-v0200">Deprecations in v0.20.0</h4><a class="anchor-link" href="#deprecations-in-v0200"><svg width="16" height="16" viewBox="0 0 24 24"><path fill="currentcolor" d="m12.11 15.39-3.88 3.88a2.52 2.52 0 0 1-3.5 0 2.47 2.47 0 0 1 0-3.5l3.88-3.88a1 1 0 0 0-1.42-1.42l-3.88 3.89a4.48 4.48 0 0 0 6.33 6.33l3.89-3.88a1 1 0 1 0-1.42-1.42Zm8.58-12.08a4.49 4.49 0 0 0-6.33 0l-3.89 3.88a1 1 0 0 0 1.42 1.42l3.88-3.88a2.52 2.52 0 0 1 3.5 0 2.47 2.47 0 0 1 0 3.5l-3.88 3.88a1 1 0 1 0 1.42 1.42l3.88-3.89a4.49 4.49 0 0 0 0-6.33ZM8.83 15.17a1 1 0 0 0 1.1.22 1 1 0 0 0 .32-.22l4.92-4.92a1 1 0 0 0-1.42-1.42l-4.92 4.92a1 1 0 0 0 0 1.42Z"></path></svg></a></div> This release deprecates the following Agents SDK APIs: <div class="table-scroll" tabindex="0" role="region" aria-label="Table"><table> <thead> <tr> <th>Deprecated API</th> <th>Replacement</th> <th>Status</th> </tr> </thead> <tbody> <tr> <td><code>McpAgent</code></td> <td>Use an SDK v2 factory with <code>createMcpHandler</code> for stateless servers. Use the migration guide to replace stateful features before removing a legacy route.</td> <td>Feature-frozen. No removal version is announced.</td> </tr> <tr> <td><code>createMcpHandler(v1Server, options)</code></td> <td>Move the server to an SDK v2 factory and call <code>createMcpHandler(factory, options)</code>. Use <code>createLegacyMcpHandler</code> only as a temporary bridge for sessionful features.</td> <td>Scheduled for removal in the next major version.</td> </tr> <tr> <td><code>MCPClientManager.callTool(params, resultSchema, options)</code> and the equivalent <code>withX402Client</code> overload</td> <td>Use <code>callTool(params, options)</code> or <code>callTool(confirm, params, options)</code>.</td> <td>Compatibility overload. No removal version is announced.</td> </tr> </tbody> </table></div> The MCP 2026-07-28 draft separately deprecates Roots, Sampling, Logging, the old HTTP+SSE transport, and Dynamic Client Registration.

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