Merge branch 'main' into use-stderr-for-logs

Author: jlowin

.github/workflows/lint.yml .github/workflows/run-static.yml

@@ -28,3 +28,9 @@ jobs:
           python-version: "3.12"
       - name: Run pre-commit
         uses: pre-commit/[email protected]
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install ".[tests]"
+      - name: Run pyright
+        run: pyright src tests

pyproject.toml

@@ -25,6 +25,7 @@ build-backend = "hatchling.build"
 [project.optional-dependencies]
 tests = [
     "pre-commit",
+    "pyright>=1.1.389",
     "pytest>=8.3.3",
     "pytest-asyncio>=0.23.5",
     "pytest-flakefinder",
@@ -39,3 +40,15 @@ asyncio_default_fixture_loop_scope = "session"
 
 [tool.hatch.version]
 source = "vcs"
+
+[tool.pyright]
+include = ["src", "tests"]
+exclude = ["**/node_modules", "**/__pycache__", ".venv", ".git", "dist"]
+pythonVersion = "3.10"
+pythonPlatform = "Darwin"
+typeCheckingMode = "basic"
+reportMissingImports = true
+reportMissingTypeStubs = false
+useLibraryCodeForTypes = true
+venvPath = "."
+venv = ".venv"

src/fastmcp/cli/cli.py

@@ -2,6 +2,7 @@
 
 import importlib.metadata
 import importlib.util
+import os
 import subprocess
 import sys
 from pathlib import Path
@@ -242,6 +243,7 @@ def dev(
             [npx_cmd, "@modelcontextprotocol/inspector"] + uv_cmd,
             check=True,
             shell=shell,
+            env=dict(os.environ.items()),  # Convert to list of tuples for env update
         )
         sys.exit(process.returncode)
     except subprocess.CalledProcessError as e:
@@ -423,7 +425,10 @@ def install(
         # Load from .env file if specified
         if env_file:
             try:
-                env_dict.update(dotenv.dotenv_values(env_file))
+                env_values = dotenv.dotenv_values(env_file)
+                env_dict.update(
+                    (k, str(v)) for k, v in env_values.items() if v is not None
+                )
             except Exception as e:
                 logger.error(f"Failed to load .env file: {e}")
                 sys.exit(1)

src/fastmcp/prompts/base.py

@@ -1,43 +1,52 @@
 """Base classes for FastMCP prompts."""
 
 import json
-from typing import Any, Callable, Dict, Literal, Optional, Sequence, Union
+from typing import Any, Callable, Dict, Literal, Optional, Sequence, Awaitable
 import inspect
 
-from pydantic import BaseModel, Field, TypeAdapter, field_validator, validate_call
+from pydantic import BaseModel, Field, TypeAdapter, validate_call
 from mcp.types import TextContent, ImageContent, EmbeddedResource
 import pydantic_core
 
+CONTENT_TYPES = TextContent | ImageContent | EmbeddedResource
+
 
 class Message(BaseModel):
     """Base class for all prompt messages."""
 
     role: Literal["user", "assistant"]
-    content: Union[TextContent, ImageContent, EmbeddedResource]
+    content: CONTENT_TYPES
 
-    def __init__(self, content, **kwargs):
+    def __init__(self, content: str | CONTENT_TYPES, **kwargs):
+        if isinstance(content, str):
+            content = TextContent(type="text", text=content)
         super().__init__(content=content, **kwargs)
 
-    @field_validator("content", mode="before")
-    def validate_content(cls, v):
-        if isinstance(v, str):
-            return TextContent(type="text", text=v)
-        return v
-
 
 class UserMessage(Message):
     """A message from the user."""
 
     role: Literal["user"] = "user"
 
+    def __init__(self, content: str | CONTENT_TYPES, **kwargs):
+        super().__init__(content=content, **kwargs)
+
 
 class AssistantMessage(Message):
     """A message from the assistant."""
 
     role: Literal["assistant"] = "assistant"
 
+    def __init__(self, content: str | CONTENT_TYPES, **kwargs):
+        super().__init__(content=content, **kwargs)
+
+
+message_validator = TypeAdapter(UserMessage | AssistantMessage)
 
-message_validator = TypeAdapter(Union[UserMessage, AssistantMessage])
+SyncPromptResult = (
+    str | Message | dict[str, Any] | Sequence[str | Message | dict[str, Any]]
+)
+PromptResult = SyncPromptResult | Awaitable[SyncPromptResult]
 
 
 class PromptArgument(BaseModel):
@@ -67,11 +76,18 @@ class Prompt(BaseModel):
     @classmethod
     def from_function(
         cls,
-        fn: Callable[..., Sequence[Message]],
+        fn: Callable[..., PromptResult],
         name: Optional[str] = None,
         description: Optional[str] = None,
     ) -> "Prompt":
-        """Create a Prompt from a function."""
+        """Create a Prompt from a function.
+
+        The function can return:
+        - A string (converted to a message)
+        - A Message object
+        - A dict (converted to a message)
+        - A sequence of any of the above
+        """
         func_name = name or fn.__name__
 
         if func_name == "<lambda>":

src/fastmcp/resources/base.py

@@ -1,14 +1,14 @@
 """Base classes and interfaces for FastMCP resources."""
 
 import abc
-from typing import Union
+from typing import Union, Annotated
 
 from pydantic import (
     AnyUrl,
     BaseModel,
     ConfigDict,
     Field,
-    FileUrl,
+    UrlConstraints,
     ValidationInfo,
     field_validator,
 )
@@ -19,8 +19,9 @@ class Resource(BaseModel, abc.ABC):
 
     model_config = ConfigDict(validate_default=True)
 
-    # uri: Annotated[AnyUrl, BeforeValidator(maybe_cast_str_to_any_url)] = Field(
-    uri: AnyUrl = Field(default=..., description="URI of the resource")
+    uri: Annotated[AnyUrl, UrlConstraints(host_required=False)] = Field(
+        default=..., description="URI of the resource"
+    )
     name: str | None = Field(description="Name of the resource", default=None)
     description: str | None = Field(
         description="Description of the resource", default=None
@@ -31,15 +32,6 @@ class Resource(BaseModel, abc.ABC):
         pattern=r"^[a-zA-Z0-9]+/[a-zA-Z0-9\-+.]+$",
     )
 
-    @field_validator("uri", mode="before")
-    def validate_uri(cls, uri: AnyUrl | str) -> AnyUrl:
-        if isinstance(uri, str):
-            # AnyUrl doesn't support triple-slashes, but files do ("file:///absolute/path")
-            if uri.startswith("file://"):
-                return FileUrl(uri)
-            return AnyUrl(uri)
-        return uri
-
     @field_validator("name", mode="before")
     @classmethod
     def set_default_name(cls, name: str | None, info: ValidationInfo) -> str:

src/fastmcp/resources/templates.py

@@ -70,7 +70,7 @@ async def create_resource(self, uri: str, params: Dict[str, Any]) -> Resource:
                 result = await result
 
             return FunctionResource(
-                uri=uri,
+                uri=uri,  # type: ignore
                 name=self.name,
                 description=self.description,
                 mime_type=self.mime_type,

src/fastmcp/resources/types.py

@@ -8,7 +8,7 @@
 import httpx
 import pydantic.json
 import pydantic_core
-from pydantic import Field
+from pydantic import Field, ValidationInfo
 
 from fastmcp.resources.base import Resource
 
@@ -91,6 +91,15 @@ def validate_absolute_path(cls, path: Path) -> Path:
             raise ValueError("Path must be absolute")
         return path
 
+    @pydantic.field_validator("is_binary")
+    @classmethod
+    def set_binary_from_mime_type(cls, is_binary: bool, info: ValidationInfo) -> bool:
+        """Set is_binary based on mime_type if not explicitly set."""
+        if is_binary:
+            return True
+        mime_type = info.data.get("mime_type", "text/plain")
+        return not mime_type.startswith("text/")
+
     async def read(self) -> Union[str, bytes]:
         """Read the file content."""
         try:

src/fastmcp/server.py

@@ -23,6 +23,7 @@
 )
 from mcp.types import (
     Prompt as MCPPrompt,
+    PromptArgument as MCPPromptArgument,
 )
 from mcp.types import (
     Resource as MCPResource,
@@ -159,7 +160,7 @@ def get_context(self) -> "Context":
 
     async def call_tool(
         self, name: str, arguments: dict
-    ) -> Sequence[TextContent | ImageContent]:
+    ) -> Sequence[TextContent | ImageContent | EmbeddedResource]:
         """Call a tool by name with arguments."""
         context = self.get_context()
         result = await self._tool_manager.call_tool(name, arguments, context=context)
@@ -462,11 +463,11 @@ async def list_prompts(self) -> list[MCPPrompt]:
                 name=prompt.name,
                 description=prompt.description,
                 arguments=[
-                    {
-                        "name": arg.name,
-                        "description": arg.description,
-                        "required": arg.required,
-                    }
+                    MCPPromptArgument(
+                        name=arg.name,
+                        description=arg.description,
+                        required=arg.required,
+                    )
                     for arg in (prompt.arguments or [])
                 ],
             )

src/fastmcp/utilities/func_metadata.py

@@ -47,7 +47,7 @@ class FuncMetadata(BaseModel):
 
     async def call_fn_with_arg_validation(
         self,
-        fn: Callable | Awaitable,
+        fn: Callable[..., Any] | Awaitable[Any],
         fn_is_async: bool,
         arguments_to_validate: dict[str, Any],
         arguments_to_pass_directly: dict[str, Any] | None,
@@ -64,8 +64,12 @@ async def call_fn_with_arg_validation(
         arguments_parsed_dict |= arguments_to_pass_directly or {}
 
         if fn_is_async:
+            if isinstance(fn, Awaitable):
+                return await fn
             return await fn(**arguments_parsed_dict)
-        return fn(**arguments_parsed_dict)
+        if isinstance(fn, Callable):
+            return fn(**arguments_parsed_dict)
+        raise TypeError("fn must be either Callable or Awaitable")
 
     def pre_parse_json(self, data: dict[str, Any]) -> dict[str, Any]:
         """Pre-parse data from JSON.
@@ -123,6 +127,7 @@ def func_metadata(func: Callable, skip_names: Sequence[str] = ()) -> FuncMetadat
     sig = _get_typed_signature(func)
     params = sig.parameters
     dynamic_pydantic_model_params: dict[str, Any] = {}
+    globalns = getattr(func, "__globals__", {})
     for param in params.values():
         if param.name.startswith("_"):
             raise InvalidSignature(
@@ -153,7 +158,7 @@ def func_metadata(func: Callable, skip_names: Sequence[str] = ()) -> FuncMetadat
             ]
 
         field_info = FieldInfo.from_annotated_attribute(
-            annotation,
+            _get_typed_annotation(annotation, globalns),
             param.default
             if param.default is not inspect.Parameter.empty
             else PydanticUndefined,

src/fastmcp/utilities/types.py

@@ -47,7 +47,9 @@ def to_image_content(self) -> ImageContent:
         if self.path:
             with open(self.path, "rb") as f:
                 data = base64.b64encode(f.read()).decode()
-        else:
+        elif self.data is not None:
             data = base64.b64encode(self.data).decode()
+        else:
+            raise ValueError("No image data available")
 
         return ImageContent(type="image", data=data, mimeType=self._mime_type)

tests/prompts/test_base.py

@@ -1,3 +1,4 @@
+from pydantic import FileUrl
 import pytest
 from fastmcp.prompts.base import (
     Prompt,
@@ -102,7 +103,7 @@ async def fn() -> UserMessage:
                 content=EmbeddedResource(
                     type="resource",
                     resource=TextResourceContents(
-                        uri="file://file.txt",
+                        uri=FileUrl("file://file.txt"),
                         text="File contents",
                         mimeType="text/plain",
                     ),
@@ -115,7 +116,7 @@ async def fn() -> UserMessage:
                 content=EmbeddedResource(
                     type="resource",
                     resource=TextResourceContents(
-                        uri="file://file.txt",
+                        uri=FileUrl("file://file.txt"),
                         text="File contents",
                         mimeType="text/plain",
                     ),
@@ -133,7 +134,7 @@ async def fn() -> list[Message]:
                     content=EmbeddedResource(
                         type="resource",
                         resource=TextResourceContents(
-                            uri="file://file.txt",
+                            uri=FileUrl("file://file.txt"),
                             text="File contents",
                             mimeType="text/plain",
                         ),
@@ -151,7 +152,7 @@ async def fn() -> list[Message]:
                 content=EmbeddedResource(
                     type="resource",
                     resource=TextResourceContents(
-                        uri="file://file.txt",
+                        uri=FileUrl("file://file.txt"),
                         text="File contents",
                         mimeType="text/plain",
                     ),
@@ -171,7 +172,7 @@ async def fn() -> dict:
                 "content": {
                     "type": "resource",
                     "resource": {
-                        "uri": "file://file.txt",
+                        "uri": FileUrl("file://file.txt"),
                         "text": "File contents",
                         "mimeType": "text/plain",
                     },
@@ -184,7 +185,7 @@ async def fn() -> dict:
                 content=EmbeddedResource(
                     type="resource",
                     resource=TextResourceContents(
-                        uri="file://file.txt",
+                        uri=FileUrl("file://file.txt"),
                         text="File contents",
                         mimeType="text/plain",
                     ),