Add support for callables (#15)

Author: ofek

docs/changelog.md

@@ -13,6 +13,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Add support for Typer
 - Add support for Argparse
 - Always set the `PYCLI_MCP_TOOL_NAME` environment variable when running commands
+- Add support for referring to a callable object that returns a command
 
 ## 0.2.0 - 2025-06-28
 

src/pycli_mcp/cli.py

@@ -116,7 +116,7 @@ def pycli_mcp(
     |_|     \\__  |\\______)_______)_|  |_|   |_|\\______)_|
            (____/
 
-    Run an MCP server using a list of import paths to commands:
+    Run an MCP server using a list of import paths to commands or callable objects that return a command:
 
     \b
     ```

src/pycli_mcp/metadata/query.py

@@ -77,6 +77,26 @@ def walk_commands(
     if aggregate is None:
         aggregate = "root"
 
+    yield from _walk_commands(
+        command,
+        aggregate=aggregate,
+        name=name,
+        include=include,
+        exclude=exclude,
+        strict_types=strict_types,
+    )
+
+
+def _walk_commands(
+    command: Any,
+    *,
+    aggregate: Literal["root", "group", "none"],
+    name: str | None,
+    include: str | re.Pattern | None,
+    exclude: str | re.Pattern | None,
+    strict_types: bool,
+    depth: int = 0,
+) -> Iterator[CommandMetadata]:
     # Click
     if hasattr(command, "context_class"):
         from pycli_mcp.metadata.types.click import walk_commands as walk_click_commands
@@ -124,5 +144,21 @@ def walk_commands(
             )
             return
 
+    if callable(command):
+        if depth > 0:
+            msg = "Callable did not return a known command type"
+            raise NotImplementedError(msg)
+
+        yield from _walk_commands(
+            command(),
+            aggregate=aggregate,
+            name=name,
+            include=include,
+            exclude=exclude,
+            strict_types=strict_types,
+            depth=depth + 1,
+        )
+        return
+
     msg = f"Unsupported command type: {type(command)}"
     raise NotImplementedError(msg)

tests/click/test_collection.py

@@ -41,6 +41,36 @@ def cli() -> None:
     assert not metadata.options
 
 
+def test_dynamic() -> None:
+    from pycli_mcp.metadata.query import walk_commands
+
+    def func() -> click.Command:
+        @click.command()
+        def cli() -> None:
+            # fmt: off
+            """
+
+                text
+                    nested
+
+            """
+            # fmt: on
+
+        return cli
+
+    commands = list(walk_commands(func, aggregate="none"))
+    assert len(commands) == 1, commands
+
+    metadata = commands[0]
+    assert metadata.path == "cli"
+    assert metadata.schema == {
+        "description": "text\n    nested",
+        "properties": {},
+        "title": "cli",
+        "type": "object",
+    }
+
+
 def test_nested_commands() -> None:
     @click.group()
     def cli() -> None: