From 00ce37b6140af1ff5add6ad5de729343820b01fe Mon Sep 17 00:00:00 2001
From: Carson <cpsievert1@gmail.com>
Date: Mon, 24 Nov 2025 10:34:47 -0600
Subject: [PATCH 1/8] fix(pkg-py): allow full client object to read, but not
 set (after initialization)

---
 pkg-py/src/querychat/_querychat.py | 44 ++++++++++++++----------------
 1 file changed, 20 insertions(+), 24 deletions(-)

diff --git a/pkg-py/src/querychat/_querychat.py b/pkg-py/src/querychat/_querychat.py
index 3e4f59f5..6179c1c1 100644
--- a/pkg-py/src/querychat/_querychat.py
+++ b/pkg-py/src/querychat/_querychat.py
@@ -114,7 +114,7 @@ def __init__(
 
         self.id = id or table_name
 
-        self.client = normalize_client(client)
+        self._client = normalize_client(client)
 
         if greeting is None:
             print(
@@ -306,7 +306,7 @@ def _server(self, *, enable_bookmarking: bool = False) -> None:
             data_source=self.data_source,
             system_prompt=self.system_prompt,
             greeting=self.greeting,
-            client=self.client,
+            client=self._client,
             enable_bookmarking=enable_bookmarking,
         )
 
@@ -416,7 +416,22 @@ def title(self, value: Optional[str] = None) -> str | None | bool:
         else:
             return vals.title.set(value)
 
-    def generate_greeting(self, *, echo: Literal["none", "text"] = "none"):
+    def client(self):
+        """
+        Obtain the chat client being used by this QueryChat instance.
+
+        Returns
+        -------
+        :
+            None
+
+        """
+        vals = self._server_values
+        if vals is None:
+            raise RuntimeError("Must call .server() before .client()")
+        return vals.client
+
+    def generate_greeting(self, *, echo: Literal["none", "output"] = "none"):
         """
         Generate a welcome greeting for the chat.
 
@@ -428,7 +443,7 @@ def generate_greeting(self, *, echo: Literal["none", "text"] = "none"):
         Parameters
         ----------
         echo
-            If `echo = "text"`, prints the greeting to standard output. If
+            If `echo = "output"`, prints the greeting to standard output. If
             `echo = "none"` (default), does not print anything.
 
         Returns
@@ -437,7 +452,7 @@ def generate_greeting(self, *, echo: Literal["none", "text"] = "none"):
             The greeting string (in Markdown format).
 
         """
-        client = copy.deepcopy(self.client)
+        client = copy.deepcopy(self._client)
         client.system_prompt = self.system_prompt
         client.set_turns([])
         prompt = "Please give me a friendly greeting. Include a few sample prompts in a two-level bulleted list."
@@ -510,25 +525,6 @@ def set_data_source(
         """
         self.data_source = normalize_data_source(data_source, table_name)
 
-    def set_client(self, client: str | chatlas.Chat) -> None:
-        """
-        Set a new chat client for the QueryChat object.
-
-        Parameters
-        ----------
-        client
-            A `chatlas.Chat` object or a string to be passed to
-            `chatlas.ChatAuto()` describing the model to use (e.g.
-            `"openai/gpt-4.1"`).
-
-        Returns
-        -------
-        :
-            None
-
-        """
-        self.client = normalize_client(client)
-
 
 class QueryChat(QueryChatBase):
     def server(self, *, enable_bookmarking: bool = False) -> None:

From d99e57f1d6e50a917437264b962feaf48f2b8877 Mon Sep 17 00:00:00 2001
From: Carson <cpsievert1@gmail.com>
Date: Mon, 24 Nov 2025 10:41:45 -0600
Subject: [PATCH 2/8] fix(pkg-py): make .data_source a read-only property

---
 pkg-py/src/querychat/_querychat.py | 26 +++++++++-----------------
 1 file changed, 9 insertions(+), 17 deletions(-)

diff --git a/pkg-py/src/querychat/_querychat.py b/pkg-py/src/querychat/_querychat.py
index 6179c1c1..d510fc44 100644
--- a/pkg-py/src/querychat/_querychat.py
+++ b/pkg-py/src/querychat/_querychat.py
@@ -104,7 +104,7 @@ def __init__(
         ```
 
         """
-        self.data_source = normalize_data_source(data_source, table_name)
+        self._data_source = normalize_data_source(data_source, table_name)
 
         # Validate table name (must begin with letter, contain only letters, numbers, underscores)
         if not re.match(r"^[a-zA-Z][a-zA-Z0-9_]*$", table_name):
@@ -127,7 +127,7 @@ def __init__(
         self.greeting = greeting.read_text() if isinstance(greeting, Path) else greeting
 
         self.system_prompt = get_system_prompt(
-            self.data_source,
+            self._data_source,
             data_description=data_description,
             extra_instructions=extra_instructions,
             prompt_template=prompt_template,
@@ -160,7 +160,7 @@ def app(
 
         """
         enable_bookmarking = bookmark_store != "disable"
-        table_name = self.data_source.table_name
+        table_name = self._data_source.table_name
 
         def app_ui(request):
             return ui.page_sidebar(
@@ -303,7 +303,7 @@ def _server(self, *, enable_bookmarking: bool = False) -> None:
         # Call the server module
         self._server_values = mod_server(
             self.id,
-            data_source=self.data_source,
+            data_source=self._data_source,
             system_prompt=self.system_prompt,
             greeting=self.greeting,
             client=self._client,
@@ -504,26 +504,18 @@ def set_system_prompt(
             prompt_template=prompt_template,
         )
 
-    def set_data_source(
-        self, data_source: IntoFrame | sqlalchemy.Engine | DataSource, table_name: str
-    ) -> None:
+    @property
+    def data_source(self):
         """
-        Set a new data source for the QueryChat object.
-
-        Parameters
-        ----------
-        data_source
-            The new data source to use.
-        table_name
-            If a data_source is a data frame, a name to use to refer to the table
+        Get the current data source.
 
         Returns
         -------
         :
-            None
+            The current data source.
 
         """
-        self.data_source = normalize_data_source(data_source, table_name)
+        return self._data_source
 
 
 class QueryChat(QueryChatBase):

From c00b9baec5881e7ef4a994e5ee2805935c5c64d3 Mon Sep 17 00:00:00 2001
From: Carson <cpsievert1@gmail.com>
Date: Mon, 24 Nov 2025 11:00:09 -0600
Subject: [PATCH 3/8] fix(pkg-py): fix setting of system prompt after
 server-initialization

---
 pkg-py/src/querychat/_querychat.py | 112 +++++++++++++++--------------
 1 file changed, 57 insertions(+), 55 deletions(-)

diff --git a/pkg-py/src/querychat/_querychat.py b/pkg-py/src/querychat/_querychat.py
index d510fc44..676e5e2d 100644
--- a/pkg-py/src/querychat/_querychat.py
+++ b/pkg-py/src/querychat/_querychat.py
@@ -40,6 +40,7 @@ def __init__(
         greeting: Optional[str | Path] = None,
         client: Optional[str | chatlas.Chat] = None,
         data_description: Optional[str | Path] = None,
+        categorical_threshold: int = 10,
         extra_instructions: Optional[str | Path] = None,
         prompt_template: Optional[str | Path] = None,
     ):
@@ -79,6 +80,9 @@ def __init__(
             Description of the data in plain text or Markdown. If a pathlib.Path
             object is passed, querychat will read the contents of the path into a
             string with `.read_text()`.
+        categorical_threshold
+            Threshold for determining if a column is categorical based on number of
+            unique values.
         extra_instructions
             Additional instructions for the chat model. If a pathlib.Path object is
             passed, querychat will read the contents of the path into a string with
@@ -126,10 +130,11 @@ def __init__(
 
         self.greeting = greeting.read_text() if isinstance(greeting, Path) else greeting
 
-        self.system_prompt = get_system_prompt(
+        self._system_prompt = get_system_prompt(
             self._data_source,
             data_description=data_description,
             extra_instructions=extra_instructions,
+            categorical_threshold=categorical_threshold,
             prompt_template=prompt_template,
         )
 
@@ -304,7 +309,7 @@ def _server(self, *, enable_bookmarking: bool = False) -> None:
         self._server_values = mod_server(
             self.id,
             data_source=self._data_source,
-            system_prompt=self.system_prompt,
+            system_prompt=self._system_prompt,
             greeting=self.greeting,
             client=self._client,
             enable_bookmarking=enable_bookmarking,
@@ -416,21 +421,6 @@ def title(self, value: Optional[str] = None) -> str | None | bool:
         else:
             return vals.title.set(value)
 
-    def client(self):
-        """
-        Obtain the chat client being used by this QueryChat instance.
-
-        Returns
-        -------
-        :
-            None
-
-        """
-        vals = self._server_values
-        if vals is None:
-            raise RuntimeError("Must call .server() before .client()")
-        return vals.client
-
     def generate_greeting(self, *, echo: Literal["none", "output"] = "none"):
         """
         Generate a welcome greeting for the chat.
@@ -453,56 +443,68 @@ def generate_greeting(self, *, echo: Literal["none", "output"] = "none"):
 
         """
         client = copy.deepcopy(self._client)
-        client.system_prompt = self.system_prompt
+        client.system_prompt = self._system_prompt
         client.set_turns([])
         prompt = "Please give me a friendly greeting. Include a few sample prompts in a two-level bulleted list."
         return str(client.chat(prompt, echo=echo))
 
-    def set_system_prompt(
-        self,
-        data_source: DataSource,
-        *,
-        data_description: Optional[str | Path] = None,
-        extra_instructions: Optional[str | Path] = None,
-        categorical_threshold: int = 10,
-        prompt_template: Optional[str | Path] = None,
-    ) -> None:
+    @property
+    def client(self):
         """
-        Customize the system prompt.
+        Obtain the underlying chat client.
 
-        Control the logic behind how the system prompt is generated based on the
-        data source's schema and optional additional context and instructions.
+        If called before `.server()`, this returns the base client provided at
+        initialization. If called after `.server()`, this returns the session-specific
+        client used for the active Shiny session.
 
-        Note
-        ----
-        This method is for parametrized system prompt generation only. To set a
-        fully custom system prompt string, set the `system_prompt` attribute
-        directly.
+        Returns
+        -------
+        :
+            None
+
+        """
+        vals = self._server_values
+        if vals is None:
+            return self._client
+        else:
+            return vals.client
+
+    @property
+    def system_prompt(self):
+        """
+        Get the current system prompt.
+
+        Returns
+        -------
+        :
+            The current system prompt.
+
+        """
+        vals = self._server_values
+        if vals is None:
+            return self._system_prompt
+        else:
+            return vals.client.system_prompt
+
+    @system_prompt.setter
+    def system_prompt(self, value: str):
+        """
+        Set a new system prompt.
 
         Parameters
         ----------
-        data_source
-            A data source to generate schema information from
-        data_description
-            Optional description of the data, in plain text or Markdown format
-        extra_instructions
-            Optional additional instructions for the chat model, in plain text or
-            Markdown format
-        categorical_threshold
-            Threshold for determining if a column is categorical based on number of
-            unique values
-        prompt_template
-            Optional `Path` to or string of a custom prompt template. If not provided, the default
-            querychat template will be used.
+        value
+            The new system prompt string.
+
+        Returns
+        -------
+        :
+            None
 
         """
-        self.system_prompt = get_system_prompt(
-            data_source,
-            data_description=data_description,
-            extra_instructions=extra_instructions,
-            categorical_threshold=categorical_threshold,
-            prompt_template=prompt_template,
-        )
+        self._system_prompt = value
+        if self._server_values is not None:
+            self._server_values.client.system_prompt = value
 
     @property
     def data_source(self):

From a2d4156061c1687b5a810e7ea3fac27e42a4a6f4 Mon Sep 17 00:00:00 2001
From: Carson <cpsievert1@gmail.com>
Date: Mon, 24 Nov 2025 11:33:51 -0600
Subject: [PATCH 4/8] Fork chat on init and simplify

---
 pkg-py/src/querychat/_querychat.py        | 55 ++++-------------------
 pkg-py/src/querychat/_querychat_module.py | 20 +++------
 2 files changed, 14 insertions(+), 61 deletions(-)

diff --git a/pkg-py/src/querychat/_querychat.py b/pkg-py/src/querychat/_querychat.py
index 676e5e2d..c9315064 100644
--- a/pkg-py/src/querychat/_querychat.py
+++ b/pkg-py/src/querychat/_querychat.py
@@ -118,8 +118,6 @@ def __init__(
 
         self.id = id or table_name
 
-        self._client = normalize_client(client)
-
         if greeting is None:
             print(
                 "Warning: No greeting provided; the LLM will be invoked at conversation start to generate one. "
@@ -130,7 +128,7 @@ def __init__(
 
         self.greeting = greeting.read_text() if isinstance(greeting, Path) else greeting
 
-        self._system_prompt = get_system_prompt(
+        prompt = get_system_prompt(
             self._data_source,
             data_description=data_description,
             extra_instructions=extra_instructions,
@@ -138,6 +136,12 @@ def __init__(
             prompt_template=prompt_template,
         )
 
+        client = normalize_client(client)
+        client2 = copy.deepcopy(client)
+        client2.set_turns([])
+        client2.system_prompt = prompt
+        self._client = client2
+
         # Populated when ._server() gets called (in an active session)
         self._server_values: ModServerResult | None = None
 
@@ -309,7 +313,6 @@ def _server(self, *, enable_bookmarking: bool = False) -> None:
         self._server_values = mod_server(
             self.id,
             data_source=self._data_source,
-            system_prompt=self._system_prompt,
             greeting=self.greeting,
             client=self._client,
             enable_bookmarking=enable_bookmarking,
@@ -443,7 +446,6 @@ def generate_greeting(self, *, echo: Literal["none", "output"] = "none"):
 
         """
         client = copy.deepcopy(self._client)
-        client.system_prompt = self._system_prompt
         client.set_turns([])
         prompt = "Please give me a friendly greeting. Include a few sample prompts in a two-level bulleted list."
         return str(client.chat(prompt, echo=echo))
@@ -463,48 +465,7 @@ def client(self):
             None
 
         """
-        vals = self._server_values
-        if vals is None:
-            return self._client
-        else:
-            return vals.client
-
-    @property
-    def system_prompt(self):
-        """
-        Get the current system prompt.
-
-        Returns
-        -------
-        :
-            The current system prompt.
-
-        """
-        vals = self._server_values
-        if vals is None:
-            return self._system_prompt
-        else:
-            return vals.client.system_prompt
-
-    @system_prompt.setter
-    def system_prompt(self, value: str):
-        """
-        Set a new system prompt.
-
-        Parameters
-        ----------
-        value
-            The new system prompt string.
-
-        Returns
-        -------
-        :
-            None
-
-        """
-        self._system_prompt = value
-        if self._server_values is not None:
-            self._server_values.client.system_prompt = value
+        return self._client
 
     @property
     def data_source(self):
diff --git a/pkg-py/src/querychat/_querychat_module.py b/pkg-py/src/querychat/_querychat_module.py
index 6153a5b8..02175975 100644
--- a/pkg-py/src/querychat/_querychat_module.py
+++ b/pkg-py/src/querychat/_querychat_module.py
@@ -1,6 +1,5 @@
 from __future__ import annotations
 
-import copy
 from dataclasses import dataclass
 from pathlib import Path
 from typing import TYPE_CHECKING, Callable, Union
@@ -48,7 +47,6 @@ class ModServerResult:
     df: Callable[[], pd.DataFrame]
     sql: ReactiveString
     title: ReactiveStringOrNone
-    client: chatlas.Chat
 
 
 @module.server
@@ -58,7 +56,6 @@ def mod_server(
     session: Session,
     *,
     data_source: DataSource,
-    system_prompt: str,
     greeting: str | None,
     client: chatlas.Chat,
     enable_bookmarking: bool,
@@ -68,20 +65,15 @@ def mod_server(
     title = ReactiveStringOrNone(None)
     has_greeted = reactive.value[bool](False)  # noqa: FBT003
 
-    # Set up the chat object for this session
-    chat = copy.deepcopy(client)
-    chat.set_turns([])
-    chat.system_prompt = system_prompt
-
     # Create the tool functions
     update_dashboard_tool = tool_update_dashboard(data_source, sql, title)
     reset_dashboard_tool = tool_reset_dashboard(sql, title)
     query_tool = tool_query(data_source)
 
     # Register tools with annotations for the UI
-    chat.register_tool(update_dashboard_tool)
-    chat.register_tool(query_tool)
-    chat.register_tool(reset_dashboard_tool)
+    client.register_tool(update_dashboard_tool)
+    client.register_tool(query_tool)
+    client.register_tool(reset_dashboard_tool)
 
     # Execute query when SQL changes
     @reactive.calc
@@ -97,7 +89,7 @@ def filtered_df():
     # Handle user input
     @chat_ui.on_user_submit
     async def _(user_input: str):
-        stream = await chat.stream_async(user_input, echo="none", content="all")
+        stream = await client.stream_async(user_input, echo="none", content="all")
         await chat_ui.append_message_stream(stream)
 
     @reactive.effect
@@ -108,7 +100,7 @@ async def greet_on_startup():
         if greeting:
             await chat_ui.append_message(greeting)
         elif greeting is None:
-            stream = await chat.stream_async(
+            stream = await client.stream_async(
                 "Please give me a friendly greeting. Include a few sample prompts in a two-level bulleted list.",
                 echo="none",
             )
@@ -153,4 +145,4 @@ def _on_restore(x: RestoreState) -> None:
             if "querychat_has_greeted" in vals:
                 has_greeted.set(vals["querychat_has_greeted"])
 
-    return ModServerResult(df=filtered_df, sql=sql, title=title, client=chat)
+    return ModServerResult(df=filtered_df, sql=sql, title=title)

From 605ed385bc5202e387dcb1dbb5be7cb6e7402a81 Mon Sep 17 00:00:00 2001
From: Carson <cpsievert1@gmail.com>
Date: Mon, 24 Nov 2025 11:38:38 -0600
Subject: [PATCH 5/8] Make client an attribute

---
 pkg-py/src/querychat/_querychat.py | 23 +++--------------------
 1 file changed, 3 insertions(+), 20 deletions(-)

diff --git a/pkg-py/src/querychat/_querychat.py b/pkg-py/src/querychat/_querychat.py
index c9315064..f1d49e05 100644
--- a/pkg-py/src/querychat/_querychat.py
+++ b/pkg-py/src/querychat/_querychat.py
@@ -140,7 +140,7 @@ def __init__(
         client2 = copy.deepcopy(client)
         client2.set_turns([])
         client2.system_prompt = prompt
-        self._client = client2
+        self.client = client2
 
         # Populated when ._server() gets called (in an active session)
         self._server_values: ModServerResult | None = None
@@ -314,7 +314,7 @@ def _server(self, *, enable_bookmarking: bool = False) -> None:
             self.id,
             data_source=self._data_source,
             greeting=self.greeting,
-            client=self._client,
+            client=self.client,
             enable_bookmarking=enable_bookmarking,
         )
 
@@ -445,28 +445,11 @@ def generate_greeting(self, *, echo: Literal["none", "output"] = "none"):
             The greeting string (in Markdown format).
 
         """
-        client = copy.deepcopy(self._client)
+        client = copy.deepcopy(self.client)
         client.set_turns([])
         prompt = "Please give me a friendly greeting. Include a few sample prompts in a two-level bulleted list."
         return str(client.chat(prompt, echo=echo))
 
-    @property
-    def client(self):
-        """
-        Obtain the underlying chat client.
-
-        If called before `.server()`, this returns the base client provided at
-        initialization. If called after `.server()`, this returns the session-specific
-        client used for the active Shiny session.
-
-        Returns
-        -------
-        :
-            None
-
-        """
-        return self._client
-
     @property
     def data_source(self):
         """

From 5b89762244e60aaeea94095b781f8fb20bba90ee Mon Sep 17 00:00:00 2001
From: Carson <cpsievert1@gmail.com>
Date: Mon, 24 Nov 2025 11:51:16 -0600
Subject: [PATCH 6/8] Cleanup

---
 pkg-py/src/querychat/_querychat.py | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/pkg-py/src/querychat/_querychat.py b/pkg-py/src/querychat/_querychat.py
index f1d49e05..0f60e18a 100644
--- a/pkg-py/src/querychat/_querychat.py
+++ b/pkg-py/src/querychat/_querychat.py
@@ -137,10 +137,9 @@ def __init__(
         )
 
         client = normalize_client(client)
-        client2 = copy.deepcopy(client)
-        client2.set_turns([])
-        client2.system_prompt = prompt
-        self.client = client2
+        self.client = copy.deepcopy(client)
+        self.client.set_turns([])
+        self.client.system_prompt = prompt
 
         # Populated when ._server() gets called (in an active session)
         self._server_values: ModServerResult | None = None

From 6406f9b502546af03dbeffeb9c9155a25945f1b4 Mon Sep 17 00:00:00 2001
From: Carson <cpsievert1@gmail.com>
Date: Mon, 24 Nov 2025 12:09:22 -0600
Subject: [PATCH 7/8] Client needs to be session-specific

---
 pkg-py/src/querychat/_querychat.py        | 27 ++++++++++++++++++-----
 pkg-py/src/querychat/_querychat_module.py | 17 +++++++++-----
 2 files changed, 33 insertions(+), 11 deletions(-)

diff --git a/pkg-py/src/querychat/_querychat.py b/pkg-py/src/querychat/_querychat.py
index 0f60e18a..52136587 100644
--- a/pkg-py/src/querychat/_querychat.py
+++ b/pkg-py/src/querychat/_querychat.py
@@ -136,10 +136,11 @@ def __init__(
             prompt_template=prompt_template,
         )
 
+        # Fork and empty chat now so the per-session forks are fast
         client = normalize_client(client)
-        self.client = copy.deepcopy(client)
-        self.client.set_turns([])
-        self.client.system_prompt = prompt
+        self._client = copy.deepcopy(client)
+        self._client.set_turns([])
+        self._client.system_prompt = prompt
 
         # Populated when ._server() gets called (in an active session)
         self._server_values: ModServerResult | None = None
@@ -313,7 +314,7 @@ def _server(self, *, enable_bookmarking: bool = False) -> None:
             self.id,
             data_source=self._data_source,
             greeting=self.greeting,
-            client=self.client,
+            client=self._client,
             enable_bookmarking=enable_bookmarking,
         )
 
@@ -444,11 +445,27 @@ def generate_greeting(self, *, echo: Literal["none", "output"] = "none"):
             The greeting string (in Markdown format).
 
         """
-        client = copy.deepcopy(self.client)
+        client = copy.deepcopy(self._client)
         client.set_turns([])
         prompt = "Please give me a friendly greeting. Include a few sample prompts in a two-level bulleted list."
         return str(client.chat(prompt, echo=echo))
 
+    @property
+    def client(self):
+        """
+        Get the (session-specific) chat client.
+
+        Returns
+        -------
+        :
+            The current chat client.
+
+        """
+        vals = self._server_values
+        if vals is None:
+            raise RuntimeError("Must call .server() before accessing .client")
+        return vals.client
+
     @property
     def data_source(self):
         """
diff --git a/pkg-py/src/querychat/_querychat_module.py b/pkg-py/src/querychat/_querychat_module.py
index 02175975..4fd83570 100644
--- a/pkg-py/src/querychat/_querychat_module.py
+++ b/pkg-py/src/querychat/_querychat_module.py
@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import copy
 from dataclasses import dataclass
 from pathlib import Path
 from typing import TYPE_CHECKING, Callable, Union
@@ -47,6 +48,7 @@ class ModServerResult:
     df: Callable[[], pd.DataFrame]
     sql: ReactiveString
     title: ReactiveStringOrNone
+    client: chatlas.Chat
 
 
 @module.server
@@ -65,15 +67,18 @@ def mod_server(
     title = ReactiveStringOrNone(None)
     has_greeted = reactive.value[bool](False)  # noqa: FBT003
 
+    # Set up the chat object for this session
+    chat = copy.deepcopy(client)
+
     # Create the tool functions
     update_dashboard_tool = tool_update_dashboard(data_source, sql, title)
     reset_dashboard_tool = tool_reset_dashboard(sql, title)
     query_tool = tool_query(data_source)
 
     # Register tools with annotations for the UI
-    client.register_tool(update_dashboard_tool)
-    client.register_tool(query_tool)
-    client.register_tool(reset_dashboard_tool)
+    chat.register_tool(update_dashboard_tool)
+    chat.register_tool(query_tool)
+    chat.register_tool(reset_dashboard_tool)
 
     # Execute query when SQL changes
     @reactive.calc
@@ -89,7 +94,7 @@ def filtered_df():
     # Handle user input
     @chat_ui.on_user_submit
     async def _(user_input: str):
-        stream = await client.stream_async(user_input, echo="none", content="all")
+        stream = await chat.stream_async(user_input, echo="none", content="all")
         await chat_ui.append_message_stream(stream)
 
     @reactive.effect
@@ -100,7 +105,7 @@ async def greet_on_startup():
         if greeting:
             await chat_ui.append_message(greeting)
         elif greeting is None:
-            stream = await client.stream_async(
+            stream = await chat.stream_async(
                 "Please give me a friendly greeting. Include a few sample prompts in a two-level bulleted list.",
                 echo="none",
             )
@@ -145,4 +150,4 @@ def _on_restore(x: RestoreState) -> None:
             if "querychat_has_greeted" in vals:
                 has_greeted.set(vals["querychat_has_greeted"])
 
-    return ModServerResult(df=filtered_df, sql=sql, title=title)
+    return ModServerResult(df=filtered_df, sql=sql, title=title, client=chat)

From d390a83721854cce8aa83c3a1355beb2d3a88afa Mon Sep 17 00:00:00 2001
From: Carson <cpsievert1@gmail.com>
Date: Mon, 24 Nov 2025 12:22:05 -0600
Subject: [PATCH 8/8] Update tests

---
 pkg-py/tests/test_init_with_pandas.py |  6 ------
 pkg-py/tests/test_querychat.py        | 29 ---------------------------
 2 files changed, 35 deletions(-)

diff --git a/pkg-py/tests/test_init_with_pandas.py b/pkg-py/tests/test_init_with_pandas.py
index 3f94b639..7c182639 100644
--- a/pkg-py/tests/test_init_with_pandas.py
+++ b/pkg-py/tests/test_init_with_pandas.py
@@ -39,10 +39,6 @@ def test_init_with_pandas_dataframe():
 
     # Verify the result is properly configured
     assert qc is not None
-    assert hasattr(qc, "data_source")
-    assert hasattr(qc, "system_prompt")
-    assert hasattr(qc, "greeting")
-    assert hasattr(qc, "client")
 
 
 def test_init_with_narwhals_dataframe():
@@ -66,8 +62,6 @@ def test_init_with_narwhals_dataframe():
 
     # Verify the result is correctly configured
     assert qc is not None
-    assert hasattr(qc, "data_source")
-    assert hasattr(qc, "system_prompt")
 
 
 def test_init_with_narwhals_lazyframe_direct_query():
diff --git a/pkg-py/tests/test_querychat.py b/pkg-py/tests/test_querychat.py
index b8267b46..5ffce90b 100644
--- a/pkg-py/tests/test_querychat.py
+++ b/pkg-py/tests/test_querychat.py
@@ -39,10 +39,6 @@ def test_querychat_init(sample_df):
 
     # Verify basic attributes are set
     assert qc is not None
-    assert hasattr(qc, "data_source")
-    assert hasattr(qc, "system_prompt")
-    assert hasattr(qc, "greeting")
-    assert hasattr(qc, "client")
     assert qc.id == "test_table"
 
     # Even without server initialization, we should be able to query the data source
@@ -66,31 +62,6 @@ def test_querychat_custom_id(sample_df):
     assert qc.id == "custom_id"
 
 
-def test_querychat_set_methods(sample_df):
-    """Test that setter methods work."""
-    qc = QueryChat(
-        data_source=sample_df,
-        table_name="test_table",
-        greeting="Hello!",
-    )
-
-    # Test set_system_prompt
-    qc.set_system_prompt(
-        qc.data_source,
-        data_description="A test dataset",
-    )
-    assert "test dataset" in qc.system_prompt.lower()
-
-    # Test set_data_source
-    new_df = pd.DataFrame({"x": [1, 2, 3]})
-    qc.set_data_source(new_df, "new_table")
-    assert qc.data_source is not None
-
-    # Test set_client
-    qc.set_client("openai/gpt-4o-mini")
-    assert qc.client is not None
-
-
 def test_querychat_core_reactive_access_before_server_raises(sample_df):
     """Test that accessing reactive properties before .server() raises error."""
     qc = QueryChat(