llama-stack/llama_stack/distribution/ui/page/playground/tools.py
Michael Clifford fe9b5ef08b
fix: tools page on playground resets agent after every interaction (#2044)
# What does this PR do?

This PR updates how the `AgentType` gets set using the radio button on
the tools page of the playground. This change is needed due to the fact
with its current implementation, the chat interface will resets after
every input, preventing users from having a multi-turn conversation with
the agent.

## Test Plan

Run the Playground without these changes:
```bash
streamlit run llama_stack/distribution/ui/app.py
```
Navigate to the tools page and attempt to have a multi-turn
conversation. You should see the conversation reset after asking a
second question.

Repeat the steps above with these changes and you will see that it works
as expected when asking the agent multiple questions.

Signed-off-by: Michael Clifford <mcliffor@redhat.com>
2025-04-28 23:13:27 +02:00

352 lines
15 KiB
Python

# Copyright (c) Meta Platforms, Inc. and affiliates.
# All rights reserved.
#
# This source code is licensed under the terms described in the LICENSE file in
# the root directory of this source tree.
import enum
import json
import uuid
import streamlit as st
from llama_stack_client import Agent
from llama_stack_client.lib.agents.react.agent import ReActAgent
from llama_stack_client.lib.agents.react.tool_parser import ReActOutput
from llama_stack.distribution.ui.modules.api import llama_stack_api
class AgentType(enum.Enum):
REGULAR = "Regular"
REACT = "ReAct"
def tool_chat_page():
st.title("🛠 Tools")
client = llama_stack_api.client
models = client.models.list()
model_list = [model.identifier for model in models if model.api_model_type == "llm"]
tool_groups = client.toolgroups.list()
tool_groups_list = [tool_group.identifier for tool_group in tool_groups]
mcp_tools_list = [tool for tool in tool_groups_list if tool.startswith("mcp::")]
builtin_tools_list = [tool for tool in tool_groups_list if not tool.startswith("mcp::")]
selected_vector_dbs = []
def reset_agent():
st.session_state.clear()
st.cache_resource.clear()
with st.sidebar:
st.title("Configuration")
st.subheader("Model")
model = st.selectbox(label="Model", options=model_list, on_change=reset_agent, label_visibility="collapsed")
st.subheader("Available ToolGroups")
toolgroup_selection = st.pills(
label="Built-in tools",
options=builtin_tools_list,
selection_mode="multi",
on_change=reset_agent,
format_func=lambda tool: "".join(tool.split("::")[1:]),
help="List of built-in tools from your llama stack server.",
)
if "builtin::rag" in toolgroup_selection:
vector_dbs = llama_stack_api.client.vector_dbs.list() or []
if not vector_dbs:
st.info("No vector databases available for selection.")
vector_dbs = [vector_db.identifier for vector_db in vector_dbs]
selected_vector_dbs = st.multiselect(
label="Select Document Collections to use in RAG queries",
options=vector_dbs,
on_change=reset_agent,
)
mcp_selection = st.pills(
label="MCP Servers",
options=mcp_tools_list,
selection_mode="multi",
on_change=reset_agent,
format_func=lambda tool: "".join(tool.split("::")[1:]),
help="List of MCP servers registered to your llama stack server.",
)
toolgroup_selection.extend(mcp_selection)
grouped_tools = {}
total_tools = 0
for toolgroup_id in toolgroup_selection:
tools = client.tools.list(toolgroup_id=toolgroup_id)
grouped_tools[toolgroup_id] = [tool.identifier for tool in tools]
total_tools += len(tools)
st.markdown(f"Active Tools: 🛠 {total_tools}")
for group_id, tools in grouped_tools.items():
with st.expander(f"🔧 Tools from `{group_id}`"):
for idx, tool in enumerate(tools, start=1):
st.markdown(f"{idx}. `{tool.split(':')[-1]}`")
st.subheader("Agent Configurations")
st.subheader("Agent Type")
agent_type = st.radio(
label="Select Agent Type",
options=["Regular", "ReAct"],
on_change=reset_agent,
)
if agent_type == "ReAct":
agent_type = AgentType.REACT
else:
agent_type = AgentType.REGULAR
max_tokens = st.slider(
"Max Tokens",
min_value=0,
max_value=4096,
value=512,
step=64,
help="The maximum number of tokens to generate",
on_change=reset_agent,
)
for i, tool_name in enumerate(toolgroup_selection):
if tool_name == "builtin::rag":
tool_dict = dict(
name="builtin::rag",
args={
"vector_db_ids": list(selected_vector_dbs),
},
)
toolgroup_selection[i] = tool_dict
@st.cache_resource
def create_agent():
if "agent_type" in st.session_state and st.session_state.agent_type == AgentType.REACT:
return ReActAgent(
client=client,
model=model,
tools=toolgroup_selection,
response_format={
"type": "json_schema",
"json_schema": ReActOutput.model_json_schema(),
},
sampling_params={"strategy": {"type": "greedy"}, "max_tokens": max_tokens},
)
else:
return Agent(
client,
model=model,
instructions="You are a helpful assistant. When you use a tool always respond with a summary of the result.",
tools=toolgroup_selection,
sampling_params={"strategy": {"type": "greedy"}, "max_tokens": max_tokens},
)
st.session_state.agent_type = agent_type
agent = create_agent()
if "agent_session_id" not in st.session_state:
st.session_state["agent_session_id"] = agent.create_session(session_name=f"tool_demo_{uuid.uuid4()}")
session_id = st.session_state["agent_session_id"]
if "messages" not in st.session_state:
st.session_state["messages"] = [{"role": "assistant", "content": "How can I help you?"}]
for msg in st.session_state.messages:
with st.chat_message(msg["role"]):
st.markdown(msg["content"])
if prompt := st.chat_input(placeholder=""):
with st.chat_message("user"):
st.markdown(prompt)
st.session_state.messages.append({"role": "user", "content": prompt})
turn_response = agent.create_turn(
session_id=session_id,
messages=[{"role": "user", "content": prompt}],
stream=True,
)
def response_generator(turn_response):
if st.session_state.get("agent_type") == AgentType.REACT:
return _handle_react_response(turn_response)
else:
return _handle_regular_response(turn_response)
def _handle_react_response(turn_response):
current_step_content = ""
final_answer = None
tool_results = []
for response in turn_response:
if not hasattr(response.event, "payload"):
yield (
"\n\n🚨 :red[_Llama Stack server Error:_]\n"
"The response received is missing an expected `payload` attribute.\n"
"This could indicate a malformed response or an internal issue within the server.\n\n"
f"Error details: {response}"
)
return
payload = response.event.payload
if payload.event_type == "step_progress" and hasattr(payload.delta, "text"):
current_step_content += payload.delta.text
continue
if payload.event_type == "step_complete":
step_details = payload.step_details
if step_details.step_type == "inference":
yield from _process_inference_step(current_step_content, tool_results, final_answer)
current_step_content = ""
elif step_details.step_type == "tool_execution":
tool_results = _process_tool_execution(step_details, tool_results)
current_step_content = ""
else:
current_step_content = ""
if not final_answer and tool_results:
yield from _format_tool_results_summary(tool_results)
def _process_inference_step(current_step_content, tool_results, final_answer):
try:
react_output_data = json.loads(current_step_content)
thought = react_output_data.get("thought")
action = react_output_data.get("action")
answer = react_output_data.get("answer")
if answer and answer != "null" and answer is not None:
final_answer = answer
if thought:
with st.expander("🤔 Thinking...", expanded=False):
st.markdown(f":grey[__{thought}__]")
if action and isinstance(action, dict):
tool_name = action.get("tool_name")
tool_params = action.get("tool_params")
with st.expander(f'🛠 Action: Using tool "{tool_name}"', expanded=False):
st.json(tool_params)
if answer and answer != "null" and answer is not None:
yield f"\n\n✅ **Final Answer:**\n{answer}"
except json.JSONDecodeError:
yield f"\n\nFailed to parse ReAct step content:\n```json\n{current_step_content}\n```"
except Exception as e:
yield f"\n\nFailed to process ReAct step: {e}\n```json\n{current_step_content}\n```"
return final_answer
def _process_tool_execution(step_details, tool_results):
try:
if hasattr(step_details, "tool_responses") and step_details.tool_responses:
for tool_response in step_details.tool_responses:
tool_name = tool_response.tool_name
content = tool_response.content
tool_results.append((tool_name, content))
with st.expander(f'⚙️ Observation (Result from "{tool_name}")', expanded=False):
try:
parsed_content = json.loads(content)
st.json(parsed_content)
except json.JSONDecodeError:
st.code(content, language=None)
else:
with st.expander("⚙️ Observation", expanded=False):
st.markdown(":grey[_Tool execution step completed, but no response data found._]")
except Exception as e:
with st.expander("⚙️ Error in Tool Execution", expanded=False):
st.markdown(f":red[_Error processing tool execution: {str(e)}_]")
return tool_results
def _format_tool_results_summary(tool_results):
yield "\n\n**Here's what I found:**\n"
for tool_name, content in tool_results:
try:
parsed_content = json.loads(content)
if tool_name == "web_search" and "top_k" in parsed_content:
yield from _format_web_search_results(parsed_content)
elif "results" in parsed_content and isinstance(parsed_content["results"], list):
yield from _format_results_list(parsed_content["results"])
elif isinstance(parsed_content, dict) and len(parsed_content) > 0:
yield from _format_dict_results(parsed_content)
elif isinstance(parsed_content, list) and len(parsed_content) > 0:
yield from _format_list_results(parsed_content)
except json.JSONDecodeError:
yield f"\n**{tool_name}** was used but returned complex data. Check the observation for details.\n"
except (TypeError, AttributeError, KeyError, IndexError) as e:
print(f"Error processing {tool_name} result: {type(e).__name__}: {e}")
def _format_web_search_results(parsed_content):
for i, result in enumerate(parsed_content["top_k"], 1):
if i <= 3:
title = result.get("title", "Untitled")
url = result.get("url", "")
content_text = result.get("content", "").strip()
yield f"\n- **{title}**\n {content_text}\n [Source]({url})\n"
def _format_results_list(results):
for i, result in enumerate(results, 1):
if i <= 3:
if isinstance(result, dict):
name = result.get("name", result.get("title", "Result " + str(i)))
description = result.get("description", result.get("content", result.get("summary", "")))
yield f"\n- **{name}**\n {description}\n"
else:
yield f"\n- {result}\n"
def _format_dict_results(parsed_content):
yield "\n```\n"
for key, value in list(parsed_content.items())[:5]:
if isinstance(value, str) and len(value) < 100:
yield f"{key}: {value}\n"
else:
yield f"{key}: [Complex data]\n"
yield "```\n"
def _format_list_results(parsed_content):
yield "\n"
for _, item in enumerate(parsed_content[:3], 1):
if isinstance(item, str):
yield f"- {item}\n"
elif isinstance(item, dict) and "text" in item:
yield f"- {item['text']}\n"
elif isinstance(item, dict) and len(item) > 0:
first_value = next(iter(item.values()))
if isinstance(first_value, str) and len(first_value) < 100:
yield f"- {first_value}\n"
def _handle_regular_response(turn_response):
for response in turn_response:
if hasattr(response.event, "payload"):
print(response.event.payload)
if response.event.payload.event_type == "step_progress":
if hasattr(response.event.payload.delta, "text"):
yield response.event.payload.delta.text
if response.event.payload.event_type == "step_complete":
if response.event.payload.step_details.step_type == "tool_execution":
if response.event.payload.step_details.tool_calls:
tool_name = str(response.event.payload.step_details.tool_calls[0].tool_name)
yield f'\n\n🛠 :grey[_Using "{tool_name}" tool:_]\n\n'
else:
yield "No tool_calls present in step_details"
else:
yield f"Error occurred in the Llama Stack Cluster: {response}"
with st.chat_message("assistant"):
response_content = st.write_stream(response_generator(turn_response))
st.session_state.messages.append({"role": "assistant", "content": response_content})
tool_chat_page()