Release / 19 Oct 2026

Model Context Protocol servers v2.0.0

Connect clients using the 2026-07-28 protocol while continuing to serve legacy clients.

All of Model Context Protocol servers

Before you upgrade to v2.0.0

7 to fix

Install Node.js 24 or later before upgrading Everything, Filesystem, Memory or Sequential Thinking.

Action requiredAffects: Users upgrading any TypeScript reference server to 2.0.0.

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modelcontextprotocol/servers/blob/v2.0.0/src/filesystem/CHANGELOG.md

Upgrade the Python MCP dependency to `mcp>=2.3,<3`; the new Python servers require SDK 2.x.

Action requiredAffects: Users upgrading Fetch, Git or Time to 2026.10.19.

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Keep each incoming JSON-RPC message at or below 10 MiB; a larger message now closes the stdio connection.

Action requiredAffects: Clients sending large stdio messages to TypeScript servers.

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modelcontextprotocol/servers/blob/v2.0.0/src/memory/CHANGELOG.md

Handle unknown tools as JSON-RPC `-32602`, rather than `isError` results. Update error-text matching: TypeScript drops the MCP error prefix; Python uses `Error executing tool <name>: <message>` and Pydantic validation wording.

Action requiredAffects: Clients handling unknown tools or parsing server error text.

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Pass allowed directories on the command line for 2026-07-28 clients; Roots no longer supplies their allow-list. With no command-line directories, every modern tool call fails.

Action requiredRead, write, edit, search, and organize files in allowed directories.Affects: Filesystem clients switching to the 2026-07-28 protocol.

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modelcontextprotocol/servers/blob/v2.0.0/src/filesystem/CHANGELOG.md

Use the 2026-07-28 `io.modelcontextprotocol/tasks` extension for async tools. Legacy core tasks, including `tasks/result` and `tasks/list`, and legacy async task tools are no longer served.

Action requiredExercise MCP client support for tools, prompts, resources, sampling, and progress notifications.Affects: Clients testing Everything's tasks or async research, sampling or elicitation tools.

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modelcontextprotocol/servers/blob/v2.0.0/src/everything/docs/features.md

Roots, sampling, logging, and HTTP+SSE are labelled deprecated; toggle tools remain legacy-only. `get-roots-list` requests roots each call, and gzip resource names are limited to 255 characters.

Behavior changedExercise MCP client support for tools, prompts, resources, sampling, and progress notifications.Affects: Everything clients using legacy features or gzip resource names.

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modelcontextprotocol/servers/blob/v2.0.0/src/everything/CHANGELOG.md

Modern gzip resources use minted URIs readable by anyone holding the URI for ten minutes; legacy resources remain scoped to the session.

Behavior changedExercise MCP client support for tools, prompts, resources, sampling, and progress notifications.Affects: Clients consuming resources created by `gzip-file-as-resource`.

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modelcontextprotocol/servers/blob/v2.0.0/src/everything/docs/features.md

Python servers advertise prompts/resources with `listChanged: false`; only Fetch has a prompt. TypeScript tools no longer advertise `execution.taskSupport`; Everything, Memory and Sequential Thinking schemas declare JSON Schema 2020-12.

Behavior changedAffects: Clients inspecting capabilities or schemas.

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`prompts/get` always returns the Fetch prompt's registered description.

Behavior changedRetrieve web pages as Markdown or raw content and read long pages in chunks.Affects: Clients displaying Fetch prompt descriptions.

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modelcontextprotocol/servers/releases/tag/v2.0.0

For a branch named `null`, filter with `refs/heads/null` or its SHA. To branch from it, checkout `null` then omit `base_branch`; literal `null` in these optional arguments is treated as absent.

Action requiredInspect changes and commit history, stage files, commit changes, and manage Git branches.Affects: Git clients using a branch literally named null.

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modelcontextprotocol/servers/releases/tag/v2.0.0

What changed in v2.0.0

All servers serve both protocol eras over stdio; Everything also supports both on Streamable HTTP. Modern Filesystem access uses command-line directories, and Everything's task tools require the modern tasks extension.

Also: Everything demonstrates multi-round elicitation and task extensions; Time returns structured results; upgrades require newer runtimes.

TypeScript packages 2.0.0 on npm require Node.js 24+. Python servers 2026.10.19 on PyPI require Python 3.10+ and mcp>=2.3,<3.

Fixed and improved

Test `server/discover`, `input_required` rounds, `subscriptions/listen`, cache hints, multi-step elicitation, on-demand notifications, per-request logs and `x-mcp-header` mirroring.

ImprovedExercise MCP client support for tools, prompts, resources, sampling, and progress notifications.

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modelcontextprotocol/servers/blob/v2.0.0/src/everything/docs/features.md

Use Filesystem over stdio with either 2026-07-28 or 2025-era clients.

ImprovedRead, write, edit, search, and organize files in allowed directories.

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modelcontextprotocol/servers/blob/v2.0.0/src/filesystem/CHANGELOG.md

Use 2026-07-28 discovery and `subscriptions/listen` updates for `memory://knowledge-graph`; legacy resource subscriptions continue to work.

ImprovedStore, search, and update entities, observations, and relationships across chats.

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modelcontextprotocol/servers/blob/v2.0.0/src/memory/CHANGELOG.md

Record thought steps over either protocol era; history lasts for the client's connection.

ImprovedBreak problems into steps and record revisions or alternative reasoning branches.

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modelcontextprotocol/servers/blob/v2.0.0/src/sequentialthinking/CHANGELOG.md

Fetch pages over either 2026-07-28 or 2025-11-25 stdio connections; the first client request selects the era.

ImprovedRetrieve web pages as Markdown or raw content and read long pages in chunks.

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modelcontextprotocol/servers/blob/v2.0.0/src/fetch/README.md

Use Git tools with 2026-07-28 or 2025-11-25 stdio clients; `git_show` patch headers now prefix paths with `a/` and `b/`.

ImprovedInspect changes and commit history, stage files, commit changes, and manage Git branches.Inferred

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modelcontextprotocol/servers/blob/v2.0.0/src/git/src/mcp_server_git/server.py

Use Time with either protocol era; both tools now declare `outputSchema` and return `structuredContent` alongside the existing JSON text.

ImprovedLook up the current time and convert times between IANA timezones.

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modelcontextprotocol/servers/blob/v2.0.0/src/time/README.md

Seeded by @iluxav with Codex, from the release's public sources. Each change links to its evidence.