Add CLI update notifications

src/fastmcp/cli/cli.py

@@ -29,6 +29,7 @@
 )
 from fastmcp.utilities.logging import get_logger
 from fastmcp.utilities.mcp_server_config import MCPServerConfig
+from fastmcp.utilities.version_check import check_for_newer_version
 
 logger = get_logger("cli")
 console = Console()
@@ -121,6 +122,14 @@ def version(
     else:
         console.print(g)
 
+        # Check for updates (not included in --copy output)
+        if newer_version := check_for_newer_version():
+            console.print()
+            console.print(
+                f"[bold]🎉 FastMCP update available:[/bold] [green]{newer_version}[/green]"
+            )
+            console.print("[dim]Run: pip install --upgrade fastmcp[/dim]")
+
 
 @app.command
 async def dev(

src/fastmcp/settings.py

@@ -333,3 +333,18 @@ def normalize_log_level(cls, v):
             ),
         ),
     ] = True
+
+    check_for_updates: Annotated[
+        Literal["stable", "prerelease", "off"],
+        Field(
+            description=inspect.cleandoc(
+                """
+                Controls update checking when displaying the CLI banner.
+                - "stable": Check for stable releases only (default)
+                - "prerelease": Also check for pre-release versions (alpha, beta, rc)
+                - "off": Disable update checking entirely
+                Set via FASTMCP_CHECK_FOR_UPDATES environment variable.
+                """
+            ),
+        ),
+    ] = "stable"

src/fastmcp/utilities/cli.py

@@ -17,6 +17,7 @@
 from fastmcp.utilities.mcp_server_config import MCPServerConfig
 from fastmcp.utilities.mcp_server_config.v1.sources.filesystem import FileSystemSource
 from fastmcp.utilities.types import get_cached_typeadapter
+from fastmcp.utilities.version_check import check_for_newer_version
 
 if TYPE_CHECKING:
     from fastmcp import FastMCP
@@ -200,6 +201,9 @@ def load_and_merge_config(
 def log_server_banner(server: FastMCP[Any]) -> None:
     """Creates and logs a formatted banner with server information and logo."""
 
+    # Check for updates (non-blocking, fails silently)
+    newer_version = check_for_newer_version()
+
     # Create the logo text
     # Use Text with no_wrap and markup disabled to preserve ANSI escape codes
     logo_text = Text.from_ansi(LOGO_ASCII_4, no_wrap=True)
@@ -231,8 +235,10 @@ def log_server_banner(server: FastMCP[Any]) -> None:
 
     # v3 notice banner (shown below main panel)
     v3_line1 = Text("✨ FastMCP 3.0 is coming!", style="bold")
-    v3_line2 = Text(
-        "Pin fastmcp<3 in production, then upgrade when you're ready.", style="dim"
+    v3_line2 = Text.assemble(
+        ("Pin ", "dim"),
+        ("`fastmcp < 3`", "dim bold"),
+        (" in production, then upgrade when you're ready.", "dim"),
     )
     v3_notice = Panel(
         Group(Align.center(v3_line1), Align.center(v3_line2)),
@@ -250,5 +256,26 @@ def log_server_banner(server: FastMCP[Any]) -> None:
     )
 
     console = Console(stderr=True)
-    # Center both panels
-    console.print(Group("\n", Align.center(panel), Align.center(v3_notice), "\n"))
+
+    # Build output elements
+    output_elements: list[Align | Panel | str] = ["\n", Align.center(panel)]
+    output_elements.append(Align.center(v3_notice))
+
+    # Add update notice if a newer version is available (shown last for visibility)
+    if newer_version:
+        update_line1 = Text.assemble(
+            ("🎉 Update available: ", "bold"),
+            (newer_version, "bold green"),
+        )
+        update_line2 = Text("Run: pip install --upgrade fastmcp", style="dim")
+        update_notice = Panel(
+            Group(Align.center(update_line1), Align.center(update_line2)),
+            border_style="blue",
+            padding=(0, 2),
+            width=80,
+        )
+        output_elements.append(Align.center(update_notice))
+
+    output_elements.append("\n")
+
+    console.print(Group(*output_elements))

src/fastmcp/utilities/version_check.py

@@ -0,0 +1,153 @@
+"""Version checking utilities for FastMCP."""
+
+from __future__ import annotations
+
+import json
+import time
+from pathlib import Path
+
+import httpx
+from packaging.version import Version
+
+from fastmcp.utilities.logging import get_logger
+
+logger = get_logger(__name__)
+
+PYPI_URL = "https://pypi.org/pypi/fastmcp/json"
+CACHE_TTL_SECONDS = 60 * 60 * 12  # 12 hours
+REQUEST_TIMEOUT_SECONDS = 2.0
+
+
+def _get_cache_path(include_prereleases: bool = False) -> Path:
+    """Get the path to the version cache file."""
+    import fastmcp
+
+    suffix = "_prerelease" if include_prereleases else ""
+    return fastmcp.settings.home / f"version_cache{suffix}.json"
+
+
+def _read_cache(include_prereleases: bool = False) -> tuple[str | None, float]:
+    """Read cached version info.
+
+    Returns:
+        Tuple of (cached_version, cache_timestamp) or (None, 0) if no cache.
+    """
+    cache_path = _get_cache_path(include_prereleases)
+    if not cache_path.exists():
+        return None, 0
+
+    try:
+        data = json.loads(cache_path.read_text())
+        return data.get("latest_version"), data.get("timestamp", 0)
+    except (json.JSONDecodeError, OSError):
+        return None, 0
+
+
+def _write_cache(latest_version: str, include_prereleases: bool = False) -> None:
+    """Write version info to cache."""
+    cache_path = _get_cache_path(include_prereleases)
+    try:
+        cache_path.parent.mkdir(parents=True, exist_ok=True)
+        cache_path.write_text(
+            json.dumps({"latest_version": latest_version, "timestamp": time.time()})
+        )
+    except OSError:
+        # Silently ignore cache write failures
+        pass
+
+
+def _fetch_latest_version(include_prereleases: bool = False) -> str | None:
+    """Fetch the latest version from PyPI.
+
+    Args:
+        include_prereleases: If True, include pre-release versions (alpha, beta, rc).
+
+    Returns:
+        The latest version string, or None if the fetch failed.
+    """
+    try:
+        response = httpx.get(PYPI_URL, timeout=REQUEST_TIMEOUT_SECONDS)
+        response.raise_for_status()
+        data = response.json()
+
+        releases = data.get("releases", {})
+        if not releases:
+            return None
+
+        versions = []
+        for version_str in releases:
+            try:
+                v = Version(version_str)
+                # Skip prereleases if not requested
+                if not include_prereleases and v.is_prerelease:
+                    continue
+                versions.append(v)
+            except ValueError:
+                logger.debug(f"Skipping invalid version string: {version_str}")
+                continue
+
+        if not versions:
+            return None
+
+        return str(max(versions))
+
+    except (httpx.HTTPError, json.JSONDecodeError, KeyError):
+        return None
+
+
+def get_latest_version(include_prereleases: bool = False) -> str | None:
+    """Get the latest version of FastMCP from PyPI, using cache when available.
+
+    Args:
+        include_prereleases: If True, include pre-release versions.
+
+    Returns:
+        The latest version string, or None if unavailable.
+    """
+    # Check cache first
+    cached_version, cache_timestamp = _read_cache(include_prereleases)
+    if cached_version and (time.time() - cache_timestamp) < CACHE_TTL_SECONDS:
+        return cached_version
+
+    # Fetch from PyPI
+    latest_version = _fetch_latest_version(include_prereleases)
+
+    # Update cache if we got a valid version
+    if latest_version:
+        _write_cache(latest_version, include_prereleases)
+        return latest_version
+
+    # Return stale cache if available
+    return cached_version
+
+
+def check_for_newer_version() -> str | None:
+    """Check if a newer version of FastMCP is available.
+
+    Returns:
+        The latest version string if newer than current, None otherwise.
+    """
+    import fastmcp
+
+    setting = fastmcp.settings.check_for_updates
+    if setting == "off":
+        return None
+
+    include_prereleases = setting == "prerelease"
+    latest_version = get_latest_version(include_prereleases)
+    if not latest_version:
+        return None
+
+    try:
+        current = Version(fastmcp.__version__)
+        latest = Version(latest_version)
+
+        if latest > current:
+            return latest_version
+    except ValueError:
+        logger.debug(
+            f"Could not compare versions: current={fastmcp.__version__!r}, "
+            f"latest={latest_version!r}"
+        )
+
+    return None