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chore(deps): update dependency fastmcp to v3#306

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chore(deps): update dependency fastmcp to v3#306
renovate[bot] wants to merge 1 commit intomainfrom
renovate/fastmcp-3.x

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@renovate renovate bot commented Feb 18, 2026 •
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ℹ️ Note

This PR body was truncated due to platform limits.

This PR contains the following updates:

Package Change Age Adoption Passing Confidence
fastmcp >=2,<3 → >=3,<4 age adoption passing confidence

Release Notes

PrefectHQ/fastmcp (fastmcp)

v3.0.0: : Three at Last

Compare Source

FastMCP 3.0 is stable. Two betas, two release candidates, 21 new contributors, and more than 100,000 pre-release installs later — the architecture held up, the upgrade path was smooth, and we're shipping it.

The surface API is largely unchanged — @mcp.tool() still works exactly as before. What changed is everything underneath: a provider/transform architecture that makes FastMCP extensible, observable, and composable in ways v2 couldn't support. If we did our jobs right, you'll barely notice the redesign. You'll just notice that more is possible.

This is also the release where FastMCP moves from jlowin/fastmcp to PrefectHQ/fastmcp. GitHub forwards all links, PyPI is the same, imports are the same. A major version felt like the right moment to make it official.

Build servers from anything

🔌 Components no longer have to live in one file with one server. FileSystemProvider discovers tools from directories with hot-reload. OpenAPIProvider wraps REST APIs. ProxyProvider proxies remote MCP servers. SkillsProvider delivers agent skills as resources. Write your own provider for whatever source makes sense. Compose multiple providers into one server, share one across many, or chain them with transforms that rename, namespace, filter, version, and secure components as they flow to clients. ResourcesAsTools and PromptsAsTools expose non-tool components to tool-only clients.

Ship to production

🔐 Component versioning: serve @tool(version="2.0") alongside older versions from one codebase. Granular authorization on individual components with async auth checks, server-wide policies via AuthMiddleware, and scope-based access control. OAuth gets CIMD, Static Client Registration, Azure OBO via dependency injection, JWT audience validation, and confused-deputy protections. OpenTelemetry tracing with MCP semantic conventions. Response size limiting. Background tasks with distributed Redis notification and ctx.elicit() relay. Security fixes include dropping diskcache (CVE-2025-69872) and upgrading python-multipart and protobuf for additional CVEs.

Adapt per session

💾 Session state persists across requests via ctx.set_state() / ctx.get_state(). ctx.enable_components() and ctx.disable_components() let servers adapt dynamically per client — show admin tools after authentication, progressively reveal capabilities, or scope access by role.

Develop faster

⚡ --reload auto-restarts on file changes. Standalone decorators return the original function, so decorated tools stay callable in tests and non-MCP contexts. Sync functions auto-dispatch to a threadpool. Tool timeouts, MCP-compliant pagination, composable lifespans, PingMiddleware for keepalive, and concurrent tool execution when the LLM returns multiple calls in one response.

Use FastMCP as a CLI

🖥️ fastmcp list and fastmcp call query and invoke tools on any server from a terminal. fastmcp discover scans your editor configs (Claude Desktop, Cursor, Goose, Gemini CLI) and finds configured servers by name. fastmcp generate-cli writes a standalone typed CLI where every tool is a subcommand. fastmcp install registers your server with Claude Desktop, Cursor, or Goose in one command.

Build apps (3.1 preview)

📱 Spec-level support for MCP Apps is in: ui:// resource scheme, typed UI metadata via AppConfig, extension negotiation, and runtime detection. The full Apps experience lands in 3.1.

If you hit 3.0 because you didn't pin your dependencies and something breaks — the upgrade guides will get you sorted. We minimized breaking changes, but a major version is a major version.

pip install fastmcp -U

📖 Documentation
🚀 Upgrade from FastMCP v2
🔀 Upgrade from MCP Python SDK
📰 What's New in FastMCP 3.0

What's Changed

New Features 🎉
Enhancements 🔧
Fixes 🐞
Breaking Changes 🛫
Docs 📚
Dependencies 📦
Other Changes 🦾

Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

  • If you want to rebase/retry this PR, check this box

This PR was generated by Mend Renovate. View the repository job log.

@mirkolenz mirkolenz closed this Feb 19, 2026
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renovate bot commented Feb 19, 2026

Renovate Ignore Notification

Because you closed this PR without merging, Renovate will ignore this update. You will not get PRs for any future 3.x releases. But if you manually upgrade to 3.x then Renovate will re-enable minor and patch updates automatically.

If you accidentally closed this PR, or if you changed your mind: rename this PR to get a fresh replacement PR.

@renovate renovate bot deleted the renovate/fastmcp-3.x branch February 19, 2026 09:01
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