feat(servlets): eval-py servlet

servlets/eval-py/.gitignore

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+plugin.wasm
+plugin/__pycache__

servlets/eval-py/README.md

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+# Python Eval Servlet
+
+A simple servlet that evaluates Python code in a CPython Wasm sandbox and returns the result.
+
+## What it does
+
+Takes Python code as input, evaluates it using `exec()`, and returns the stdout output as a string.
+
+## Usage
+
+Call with:
+
+```json
+{
+  "arguments": {
+    "code": "print(2 + 2)"  // Required: Python code to evaluate
+  }
+}
+```
+
+Returns:
+
+```
+4
+```

servlets/eval-py/plugin/__init__.py

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+# THIS FILE WAS GENERATED BY `xtp-python-bindgen`. DO NOT EDIT.
+
+from typing import Optional, List  # noqa: F401
+from datetime import datetime  # noqa: F401
+import json
+import extism  # pyright: ignore
+import plugin
+
+
+from pdk_types import (
+    BlobResourceContents,
+    CallToolRequest,
+    CallToolResult,
+    Content,
+    ContentType,
+    ListToolsResult,
+    Params,
+    Role,
+    TextAnnotation,
+    TextResourceContents,
+    ToolDescription,
+)  # noqa: F401
+
+
+# Imports
+
+
+# Exports
+# The implementations for these functions is in `plugin.py`
+
+
+# Called when the tool is invoked.
+# If you support multiple tools, you must switch on the input.params.name to detect which tool is being called.
+@extism.plugin_fn
+def call():
+    input = extism.input_str()
+    input = CallToolRequest.from_json(input)
+    res = plugin.call(input)
+    extism.output_str(res.to_json())
+
+
+# Called by mcpx to understand how and why to use this tool.
+# Note: Your servlet configs will not be set when this function is called,
+# so do not rely on config in this function
+@extism.plugin_fn
+def describe():
+    res = plugin.describe()
+    extism.output_str(res.to_json())

servlets/eval-py/plugin/pdk_imports.py

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+# THIS FILE WAS GENERATED BY `xtp-python-bindgen`. DO NOT EDIT.
+
+from typing import Optional, List  # noqa: F401
+from datetime import datetime  # noqa: F401
+import extism  # noqa: F401 # pyright: ignore
+import json
+
+
+from pdk_types import (
+    BlobResourceContents,
+    CallToolRequest,
+    CallToolResult,
+    Content,
+    ContentType,
+    ListToolsResult,
+    Params,
+    Role,
+    TextAnnotation,
+    TextResourceContents,
+    ToolDescription,
+)  # noqa: F401

servlets/eval-py/plugin/pdk_types.py

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+# THIS FILE WAS GENERATED BY `xtp-python-bindgen`. DO NOT EDIT.
+
+from __future__ import annotations
+from enum import Enum  # noqa: F401
+from typing import Optional, List  # noqa: F401
+from datetime import datetime  # noqa: F401
+from dataclasses import dataclass  # noqa: F401
+from dataclass_wizard import JSONWizard  # noqa: F401
+from dataclass_wizard.type_def import JSONObject
+from base64 import b64encode, b64decode
+
+
+@dataclass
+class BlobResourceContents(JSONWizard):
+    # A base64-encoded string representing the binary data of the item.
+    blob: str
+
+    # The URI of this resource.
+    uri: str
+
+    # The MIME type of this resource, if known.
+    mimeType: Optional[str] = None
+
+    @classmethod
+    def _pre_from_dict(cls, o: JSONObject) -> JSONObject:
+        return o
+
+    def _pre_dict(self):
+        return
+
+
+@dataclass
+class CallToolRequest(JSONWizard):
+    params: Params
+
+    method: Optional[str] = None
+
+    @classmethod
+    def _pre_from_dict(cls, o: JSONObject) -> JSONObject:
+        return o
+
+    def _pre_dict(self):
+        return
+
+
+@dataclass
+class CallToolResult(JSONWizard):
+    content: List[Content]
+
+    # Whether the tool call ended in an error.
+    #
+    # If not set, this is assumed to be false (the call was successful).
+    isError: Optional[bool] = None
+
+    @classmethod
+    def _pre_from_dict(cls, o: JSONObject) -> JSONObject:
+        return o
+
+    def _pre_dict(self):
+        return
+
+
+@dataclass
+class Content(JSONWizard):
+    type: ContentType
+
+    annotations: Optional[TextAnnotation] = None
+
+    # The base64-encoded image data.
+    data: Optional[str] = None
+
+    # The MIME type of the image. Different providers may support different image types.
+    mimeType: Optional[str] = None
+
+    # The text content of the message.
+    text: Optional[str] = None
+
+    @classmethod
+    def _pre_from_dict(cls, o: JSONObject) -> JSONObject:
+        return o
+
+    def _pre_dict(self):
+        return
+
+
+class ContentType(Enum):
+    Text = "text"
+    Image = "image"
+    Resource = "resource"
+
+
+@dataclass
+class ListToolsResult(JSONWizard):
+    # The list of ToolDescription objects provided by this servlet.
+    tools: List[ToolDescription]
+
+    @classmethod
+    def _pre_from_dict(cls, o: JSONObject) -> JSONObject:
+        return o
+
+    def _pre_dict(self):
+        return
+
+
+@dataclass
+class Params(JSONWizard):
+    name: str
+
+    arguments: Optional[dict] = None
+
+    @classmethod
+    def _pre_from_dict(cls, o: JSONObject) -> JSONObject:
+        return o
+
+    def _pre_dict(self):
+        return
+
+
+class Role(Enum):
+    Assistant = "assistant"
+    User = "user"
+
+
+@dataclass
+class TextAnnotation(JSONWizard):
+    # Describes who the intended customer of this object or data is.
+    #
+    # It can include multiple entries to indicate content useful for multiple audiences (e.g., `["user", "assistant"]`).
+    audience: Optional[List[Role]] = None
+
+    # Describes how important this data is for operating the server.
+    #
+    # A value of 1 means "most important," and indicates that the data is
+    # effectively required, while 0 means "least important," and indicates that
+    # the data is entirely optional.
+    priority: Optional[float] = None
+
+    @classmethod
+    def _pre_from_dict(cls, o: JSONObject) -> JSONObject:
+        return o
+
+    def _pre_dict(self):
+        return
+
+
+@dataclass
+class TextResourceContents(JSONWizard):
+    # The text of the item. This must only be set if the item can actually be represented as text (not binary data).
+    text: str
+
+    # The URI of this resource.
+    uri: str
+
+    # The MIME type of this resource, if known.
+    mimeType: Optional[str] = None
+
+    @classmethod
+    def _pre_from_dict(cls, o: JSONObject) -> JSONObject:
+        return o
+
+    def _pre_dict(self):
+        return
+
+
+@dataclass
+class ToolDescription(JSONWizard):
+    # A description of the tool
+    description: str
+
+    # The JSON schema describing the argument input
+    inputSchema: dict
+
+    # The name of the tool. It should match the plugin / binding name.
+    name: str
+
+    @classmethod
+    def _pre_from_dict(cls, o: JSONObject) -> JSONObject:
+        return o
+
+    def _pre_dict(self):
+        return

servlets/eval-py/plugin/plugin.py

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+from typing import Optional, List  # noqa: F401
+from datetime import datetime  # noqa: F401
+import extism  # noqa: F401 # pyright: ignore
+import traceback
+from io import StringIO
+import sys
+
+from pdk_types import (
+    BlobResourceContents,
+    CallToolRequest,
+    CallToolResult,
+    Content,
+    ContentType,
+    ListToolsResult,
+    Params,
+    Role,
+    TextAnnotation,
+    TextResourceContents,
+    ToolDescription,
+)  # noqa: F401
+
+
+from typing import List, Optional  # noqa: F401
+
+
+# Called when the tool is invoked.
+# If you support multiple tools, you must switch on the input.params.name to detect which tool is being called.
+def call(input: CallToolRequest) -> CallToolResult:
+    try:
+        code = input.params.arguments['code']
+        output = StringIO()
+        old_stdout = sys.stdout
+        sys.stdout = output
+        exec(code)
+        sys.stdout = old_stdout
+        result = output.getvalue()
+        output.close()
+        isError = False
+    except Exception as e:
+        result = "\n".join([
+            "Traceback (most recent call last):",
+            traceback.format_tb(e.__traceback__)[0].rstrip(),
+            f"{type(e).__name__}: {e}"
+        ])
+        isError = True
+    return CallToolResult(
+        content=[
+            Content(
+                text=result,
+                mimeType="text/plain",
+                type=ContentType.Text,
+                annotations=None,
+                data=None,
+            )
+        ],
+        isError=isError,
+    )
+
+# Called by mcpx to understand how and why to use this tool.
+# Note: Your servlet configs will not be set when this function is called,
+# so do not rely on config in this function
+def describe() -> ListToolsResult:
+    return ListToolsResult(
+        [
+            ToolDescription(
+                name="eval-py",
+                description="Evaluate some Python using `exec()` in a sandbox.",
+                inputSchema={
+                    "type": "object",
+                    "properties": {
+                        "code": {
+                            "type": "string",
+                            "description": "The Python code to eval. This code gets passed into `exec()` and the stdout output is returned.",
+                        },
+                    },
+                    "required": ["code"],
+                },
+            )
+        ]
+    )