Revert "fix: allow omitting mcpServers in session requests"

This reverts commit 73499a8.

Author: PsiACE

scripts/gen_schema.py

@@ -2,23 +2,16 @@
 from __future__ import annotations
 
 import ast
-import contextlib
 import json
 import re
 import subprocess
 import sys
-import tempfile
 import textwrap
 from collections.abc import Callable
 from dataclasses import dataclass
 from pathlib import Path
 
 ROOT = Path(__file__).resolve().parents[1]
-if str(ROOT) not in sys.path:
-    sys.path.append(str(ROOT))
-
-from scripts.schema_patches import apply_schema_patches  # noqa: E402
-
 SCHEMA_DIR = ROOT / "schema"
 SCHEMA_JSON = SCHEMA_DIR / "schema.json"
 VERSION_FILE = SCHEMA_DIR / "VERSION"
@@ -143,23 +136,12 @@ def generate_schema() -> None:
         )
         sys.exit(1)
 
-    schema_payload = json.loads(SCHEMA_JSON.read_text(encoding="utf-8"))
-    schema_payload, patch_warnings = apply_schema_patches(schema_payload)
-    for warning in patch_warnings:
-        print(f"Warning: {warning.message}", file=sys.stderr)
-
-    patched_schema_path: Path | None = None
-    with tempfile.NamedTemporaryFile("w", suffix=".json", delete=False, encoding="utf-8") as handle:
-        json.dump(schema_payload, handle, indent=2)
-        handle.write("\n")
-        patched_schema_path = Path(handle.name)
-
     cmd = [
         sys.executable,
         "-m",
         "datamodel_code_generator",
         "--input",
-        str(patched_schema_path),
+        str(SCHEMA_JSON),
         "--input-file-type",
         "jsonschema",
         "--output",
@@ -173,15 +155,10 @@ def generate_schema() -> None:
         "--snake-case-field",
     ]
 
-    try:
-        subprocess.check_call(cmd)  # noqa: S603
-        warnings = postprocess_generated_schema(SCHEMA_OUT)
-        for warning in warnings:
-            print(f"Warning: {warning}", file=sys.stderr)
-    finally:
-        if patched_schema_path is not None:
-            with contextlib.suppress(OSError):
-                patched_schema_path.unlink()
+    subprocess.check_call(cmd)  # noqa: S603
+    warnings = postprocess_generated_schema(SCHEMA_OUT)
+    for warning in warnings:
+        print(f"Warning: {warning}", file=sys.stderr)
 
 
 def postprocess_generated_schema(output_path: Path) -> list[str]:

scripts/schema_patches.py

@@ -45,7 +45,6 @@
 
 __all__ = ["ClientSideConnection"]
 _CLIENT_CONNECTION_ERROR = "ClientSideConnection requires asyncio StreamWriter/StreamReader"
-_MISSING = object()
 
 
 @final
@@ -94,10 +93,7 @@ async def initialize(
 
     @param_model(NewSessionRequest)
     async def new_session(
-        self,
-        cwd: str,
-        mcp_servers: list[HttpMcpServer | SseMcpServer | McpServerStdio] | None = None,
-        **kwargs: Any,
+        self, cwd: str, mcp_servers: list[HttpMcpServer | SseMcpServer | McpServerStdio], **kwargs: Any
     ) -> NewSessionResponse:
         return await request_model(
             self._conn,
@@ -108,27 +104,12 @@ async def new_session(
 
     @param_model(LoadSessionRequest)
     async def load_session(
-        self,
-        cwd: str,
-        mcp_servers: list[HttpMcpServer | SseMcpServer | McpServerStdio] | str | None = None,
-        session_id: str | object = _MISSING,
-        **kwargs: Any,
+        self, cwd: str, mcp_servers: list[HttpMcpServer | SseMcpServer | McpServerStdio], session_id: str, **kwargs: Any
     ) -> LoadSessionResponse:
-        if session_id is _MISSING:
-            if isinstance(mcp_servers, str):
-                session_id = mcp_servers
-                mcp_servers = None
-            else:
-                raise TypeError("load_session() missing required argument: 'session_id'")
         return await request_model_from_dict(
             self._conn,
             AGENT_METHODS["session_load"],
-            LoadSessionRequest(
-                cwd=cwd,
-                mcp_servers=cast(list[HttpMcpServer | SseMcpServer | McpServerStdio] | None, mcp_servers),
-                session_id=cast(str, session_id),
-                field_meta=kwargs or None,
-            ),
+            LoadSessionRequest(cwd=cwd, mcp_servers=mcp_servers, session_id=session_id, field_meta=kwargs or None),
             LoadSessionResponse,
         )
 

src/acp/client/connection.py

@@ -154,19 +154,12 @@ async def initialize(
 
     @param_model(NewSessionRequest)
     async def new_session(
-        self,
-        cwd: str,
-        mcp_servers: list[HttpMcpServer | SseMcpServer | McpServerStdio] | None = None,
-        **kwargs: Any,
+        self, cwd: str, mcp_servers: list[HttpMcpServer | SseMcpServer | McpServerStdio], **kwargs: Any
     ) -> NewSessionResponse: ...
 
     @param_model(LoadSessionRequest)
     async def load_session(
-        self,
-        cwd: str,
-        session_id: str,
-        mcp_servers: list[HttpMcpServer | SseMcpServer | McpServerStdio] | None = None,
-        **kwargs: Any,
+        self, cwd: str, mcp_servers: list[HttpMcpServer | SseMcpServer | McpServerStdio], session_id: str, **kwargs: Any
     ) -> LoadSessionResponse | None: ...
 
     @param_model(ListSessionsRequest)

src/acp/interfaces.py

@@ -1410,12 +1410,12 @@ class NewSessionRequest(BaseModel):
     ]
     # List of MCP (Model Context Protocol) servers the agent should connect to.
     mcp_servers: Annotated[
-        Optional[List[Union[HttpMcpServer, SseMcpServer, McpServerStdio]]],
+        List[Union[HttpMcpServer, SseMcpServer, McpServerStdio]],
         Field(
             alias="mcpServers",
             description="List of MCP (Model Context Protocol) servers the agent should connect to.",
         ),
-    ] = None
+    ]
 
 
 class PermissionOption(BaseModel):
@@ -2073,12 +2073,12 @@ class LoadSessionRequest(BaseModel):
     cwd: Annotated[str, Field(description="The working directory for this session.")]
     # List of MCP servers to connect to for this session.
     mcp_servers: Annotated[
-        Optional[List[Union[HttpMcpServer, SseMcpServer, McpServerStdio]]],
+        List[Union[HttpMcpServer, SseMcpServer, McpServerStdio]],
         Field(
             alias="mcpServers",
             description="List of MCP servers to connect to for this session.",
         ),
-    ] = None
+    ]
     # The ID of the session to load.
     session_id: Annotated[str, Field(alias="sessionId", description="The ID of the session to load.")]
 

src/acp/schema.py

@@ -243,19 +243,12 @@ async def initialize(
         return InitializeResponse(protocol_version=protocol_version, agent_capabilities=None, auth_methods=[])
 
     async def new_session(
-        self,
-        cwd: str,
-        mcp_servers: list[HttpMcpServer | SseMcpServer | McpServerStdio] | None = None,
-        **kwargs: Any,
+        self, cwd: str, mcp_servers: list[HttpMcpServer | SseMcpServer | McpServerStdio], **kwargs: Any
     ) -> NewSessionResponse:
         return NewSessionResponse(session_id="test-session-123")
 
     async def load_session(
-        self,
-        cwd: str,
-        session_id: str,
-        mcp_servers: list[HttpMcpServer | SseMcpServer | McpServerStdio] | None = None,
-        **kwargs: Any,
+        self, cwd: str, mcp_servers: list[HttpMcpServer | SseMcpServer | McpServerStdio], session_id: str, **kwargs: Any
     ) -> LoadSessionResponse | None:
         return LoadSessionResponse()