Files
letta-server/letta/services/tool_executor/builtin_tool_executor.py
Matthew Zhou 129dd97902 feat: Add fetch webpage tool [LET-4188] (#4395)
* Add fetch webpage tool

* Use trafilatura for web extraction
2025-09-03 13:34:35 -07:00

463 lines
19 KiB
Python

import asyncio
import json
import time
from typing import Any, Dict, List, Literal, Optional
from pydantic import BaseModel
from letta.constants import WEB_SEARCH_MODEL_ENV_VAR_DEFAULT_VALUE, WEB_SEARCH_MODEL_ENV_VAR_NAME
from letta.functions.prompts import FIRECRAWL_SEARCH_SYSTEM_PROMPT, get_firecrawl_search_user_prompt
from letta.functions.types import SearchTask
from letta.log import get_logger
from letta.otel.tracing import trace_method
from letta.schemas.agent import AgentState
from letta.schemas.sandbox_config import SandboxConfig
from letta.schemas.tool import Tool
from letta.schemas.tool_execution_result import ToolExecutionResult
from letta.schemas.user import User
from letta.services.tool_executor.tool_executor_base import ToolExecutor
from letta.settings import model_settings, tool_settings
logger = get_logger(__name__)
class Citation(BaseModel):
"""A relevant text snippet identified by line numbers in a document."""
start_line: int # Starting line number (1-indexed)
end_line: int # Ending line number (1-indexed, inclusive)
class CitationWithText(BaseModel):
"""A citation with the actual extracted text."""
text: str # The actual extracted text from the lines
class DocumentAnalysis(BaseModel):
"""Analysis of a document's relevance to a search question."""
citations: List[Citation]
class DocumentAnalysisWithText(BaseModel):
"""Analysis with extracted text from line citations."""
citations: List[CitationWithText]
class LettaBuiltinToolExecutor(ToolExecutor):
"""Executor for built in Letta tools."""
@trace_method
async def execute(
self,
function_name: str,
function_args: dict,
tool: Tool,
actor: User,
agent_state: Optional[AgentState] = None,
sandbox_config: Optional[SandboxConfig] = None,
sandbox_env_vars: Optional[Dict[str, Any]] = None,
) -> ToolExecutionResult:
function_map = {"run_code": self.run_code, "web_search": self.web_search, "fetch_webpage": self.fetch_webpage}
if function_name not in function_map:
raise ValueError(f"Unknown function: {function_name}")
# Execute the appropriate function
function_args_copy = function_args.copy() # Make a copy to avoid modifying the original
function_response = await function_map[function_name](agent_state=agent_state, **function_args_copy)
return ToolExecutionResult(
status="success",
func_return=function_response,
agent_state=agent_state,
)
async def run_code(self, agent_state: "AgentState", code: str, language: Literal["python", "js", "ts", "r", "java"]) -> str:
from e2b_code_interpreter import AsyncSandbox
if tool_settings.e2b_api_key is None:
raise ValueError("E2B_API_KEY is not set")
sbx = await AsyncSandbox.create(api_key=tool_settings.e2b_api_key)
params = {"code": code}
if language != "python":
# Leave empty for python
params["language"] = language
res = self._llm_friendly_result(await sbx.run_code(**params))
return json.dumps(res, ensure_ascii=False)
def _llm_friendly_result(self, res):
out = {
"results": [r.text if hasattr(r, "text") else str(r) for r in res.results],
"logs": {
"stdout": getattr(res.logs, "stdout", []),
"stderr": getattr(res.logs, "stderr", []),
},
}
err = getattr(res, "error", None)
if err is not None:
out["error"] = err
return out
@trace_method
async def web_search(self, agent_state: "AgentState", tasks: List[SearchTask], limit: int = 1, return_raw: bool = True) -> str:
"""
Search the web with a list of query/question pairs and extract passages that answer the corresponding questions.
Examples:
tasks -> [
SearchTask(
query="Tesla Q1 2025 earnings report PDF",
question="What was Tesla's net profit in Q1 2025?"
),
SearchTask(
query="Letta API prebuilt tools core_memory_append",
question="What does the core_memory_append tool do in Letta?"
)
]
Args:
tasks (List[SearchTask]): A list of search tasks, each containing a `query` and a corresponding `question`.
limit (int, optional): Maximum number of URLs to fetch and analyse per task (must be > 0). Defaults to 3.
return_raw (bool, optional): If set to True, returns the raw content of the web pages.
This should be False unless otherwise specified by the user. Defaults to False.
Returns:
str: A JSON-encoded string containing a list of search results.
Each result includes ranked snippets with their source URLs and relevance scores,
corresponding to each search task.
"""
# # TODO: Temporary, maybe deprecate this field?
# if return_raw:
# logger.warning("WARNING! return_raw was set to True, we default to False always. Deprecate this field.")
# return_raw = False
try:
from firecrawl import AsyncFirecrawlApp
except ImportError:
raise ImportError("firecrawl-py is not installed in the tool execution environment")
if not tasks:
return json.dumps({"error": "No search tasks provided."})
# Convert dict objects to SearchTask objects
search_tasks = []
for task in tasks:
if isinstance(task, dict):
search_tasks.append(SearchTask(**task))
else:
search_tasks.append(task)
logger.info(f"[DEBUG] Starting web search with {len(search_tasks)} tasks, limit={limit}, return_raw={return_raw}")
# Check if the API key exists on the agent state
agent_state_tool_env_vars = agent_state.get_agent_env_vars_as_dict()
firecrawl_api_key = agent_state_tool_env_vars.get("FIRECRAWL_API_KEY") or tool_settings.firecrawl_api_key
if not firecrawl_api_key:
raise ValueError("FIRECRAWL_API_KEY is not set in environment or on agent_state tool exec environment variables.")
# Track which API key source was used
api_key_source = "agent_environment" if agent_state_tool_env_vars.get("FIRECRAWL_API_KEY") else "system_settings"
if limit <= 0:
raise ValueError("limit must be greater than 0")
# Initialize Firecrawl client
app = AsyncFirecrawlApp(api_key=firecrawl_api_key)
# Process all search tasks serially
search_results = []
for task in search_tasks:
try:
result = await self._process_single_search_task(app, task, limit, return_raw, api_key_source, agent_state)
search_results.append(result)
except Exception as e:
search_results.append(e)
# Build final response as a mapping of query -> result
final_results = {}
successful_tasks = 0
failed_tasks = 0
for i, result in enumerate(search_results):
query = search_tasks[i].query
if isinstance(result, Exception):
logger.error(f"Search task {i} failed: {result}")
failed_tasks += 1
final_results[query] = {"query": query, "question": search_tasks[i].question, "error": str(result)}
else:
successful_tasks += 1
final_results[query] = result
logger.info(f"[DEBUG] Web search completed: {successful_tasks} successful, {failed_tasks} failed")
# Build final response with api_key_source at top level
response = {"api_key_source": api_key_source, "results": final_results}
return json.dumps(response, indent=2, ensure_ascii=False)
@trace_method
async def _process_single_search_task(
self, app: "AsyncFirecrawlApp", task: SearchTask, limit: int, return_raw: bool, api_key_source: str, agent_state: "AgentState"
) -> Dict[str, Any]:
"""Process a single search task."""
from firecrawl import ScrapeOptions
logger.info(f"[DEBUG] Starting Firecrawl search for query: '{task.query}' with limit={limit}")
# Perform the search for this task
scrape_options = ScrapeOptions(
formats=["markdown"], excludeTags=["#ad", "#footer"], onlyMainContent=True, parsePDF=True, removeBase64Images=True
)
search_result = await app.search(task.query, limit=limit, scrape_options=scrape_options)
logger.info(
f"[DEBUG] Firecrawl search completed for '{task.query}': {len(search_result.get('data', [])) if search_result else 0} results"
)
if not search_result or not search_result.get("data"):
return {"query": task.query, "question": task.question, "error": "No search results found."}
# If raw results requested, return them directly
if return_raw:
return {"query": task.query, "question": task.question, "raw_results": search_result}
# Check if OpenAI API key is available for semantic parsing
if model_settings.openai_api_key:
try:
from openai import AsyncOpenAI
logger.info(f"[DEBUG] Starting OpenAI analysis for '{task.query}'")
# Initialize OpenAI client
client = AsyncOpenAI(
api_key=model_settings.openai_api_key,
)
# Process each result with OpenAI concurrently
analysis_tasks = []
results_with_markdown = []
results_without_markdown = []
for result in search_result.get("data"):
if result.get("markdown"):
# Create async task for OpenAI analysis
analysis_task = self._analyze_document_with_openai(
client, result["markdown"], task.query, task.question, agent_state
)
analysis_tasks.append(analysis_task)
results_with_markdown.append(result)
else:
results_without_markdown.append(result)
logger.info(f"[DEBUG] Starting parallel OpenAI analysis of {len(analysis_tasks)} documents for '{task.query}'")
# Fire off all OpenAI requests concurrently
analyses = await asyncio.gather(*analysis_tasks, return_exceptions=True)
logger.info(f"[DEBUG] Completed parallel OpenAI analysis of {len(analyses)} documents for '{task.query}'")
# Build processed results
processed_results = []
# Check if any analysis failed - if so, fall back to raw results
for result, analysis in zip(results_with_markdown, analyses):
if isinstance(analysis, Exception) or analysis is None:
logger.error(f"Analysis failed for {result.get('url')}, falling back to raw results")
return {"query": task.query, "question": task.question, "raw_results": search_result}
# All analyses succeeded, build processed results
for result, analysis in zip(results_with_markdown, analyses):
# Extract actual text from line number citations
analysis_with_text = None
if analysis and analysis.citations:
analysis_with_text = self._extract_text_from_line_citations(analysis, result["markdown"])
processed_results.append(
{
"url": result.get("url"),
"title": result.get("title"),
"description": result.get("description"),
"analysis": analysis_with_text.model_dump() if analysis_with_text else None,
}
)
# Add results without markdown
for result in results_without_markdown:
processed_results.append(
{"url": result.get("url"), "title": result.get("title"), "description": result.get("description"), "analysis": None}
)
# Build final response for this task
return self._build_final_response_dict(processed_results, task.query, task.question)
except Exception as e:
# Log error but continue with raw results
logger.error(f"Error with OpenAI processing for task '{task.query}': {e}")
# Return raw search results if OpenAI processing isn't available or fails
return {"query": task.query, "question": task.question, "raw_results": search_result}
@trace_method
async def _analyze_document_with_openai(
self, client, markdown_content: str, query: str, question: str, agent_state: "AgentState"
) -> Optional[DocumentAnalysis]:
"""Use OpenAI to analyze a document and extract relevant passages using line numbers."""
original_length = len(markdown_content)
# Create numbered markdown for the LLM to reference
numbered_lines = markdown_content.split("\n")
numbered_markdown = "\n".join([f"{i + 1:4d}: {line}" for i, line in enumerate(numbered_lines)])
# Truncate if too long
max_content_length = 200000
truncated = False
if len(numbered_markdown) > max_content_length:
numbered_markdown = numbered_markdown[:max_content_length] + "..."
truncated = True
user_prompt = get_firecrawl_search_user_prompt(query, question, numbered_markdown)
logger.info(
f"[DEBUG] Starting OpenAI request with line numbers - Query: '{query}', Content: {original_length} chars (truncated: {truncated})"
)
# Time the OpenAI request
start_time = time.time()
# Check agent state env vars first, then fall back to os.getenv
agent_state_tool_env_vars = agent_state.get_agent_env_vars_as_dict()
model = agent_state_tool_env_vars.get(WEB_SEARCH_MODEL_ENV_VAR_NAME) or WEB_SEARCH_MODEL_ENV_VAR_DEFAULT_VALUE
logger.info(f"Using model {model} for web search result parsing")
response = await client.beta.chat.completions.parse(
model=model,
messages=[{"role": "system", "content": FIRECRAWL_SEARCH_SYSTEM_PROMPT}, {"role": "user", "content": user_prompt}],
response_format=DocumentAnalysis,
temperature=0.1,
)
end_time = time.time()
request_duration = end_time - start_time
# Get usage statistics and output length
usage = response.usage
parsed_result = response.choices[0].message.parsed
num_citations = len(parsed_result.citations) if parsed_result else 0
# Calculate output length (minimal now - just line numbers)
output_length = 0
if parsed_result and parsed_result.citations:
for citation in parsed_result.citations:
output_length += 20 # ~20 chars for line numbers only
logger.info(f"[TIMING] OpenAI request completed in {request_duration:.2f}s - Query: '{query}'")
logger.info(f"[TOKENS] Total: {usage.total_tokens} (prompt: {usage.prompt_tokens}, completion: {usage.completion_tokens})")
logger.info(f"[OUTPUT] Citations: {num_citations}, Output chars: {output_length} (line-number based)")
return parsed_result
def _extract_text_from_line_citations(self, analysis: DocumentAnalysis, original_markdown: str) -> DocumentAnalysisWithText:
"""Extract actual text from line number citations."""
lines = original_markdown.split("\n")
citations_with_text = []
for citation in analysis.citations:
try:
# Convert to 0-indexed and ensure bounds
start_idx = max(0, citation.start_line - 1)
end_idx = min(len(lines), citation.end_line)
# Extract the lines
extracted_lines = lines[start_idx:end_idx]
extracted_text = "\n".join(extracted_lines)
citations_with_text.append(CitationWithText(text=extracted_text))
except Exception as e:
logger.info(f"[DEBUG] Failed to extract text for citation lines {citation.start_line}-{citation.end_line}: {e}")
# Fall back to including the citation with empty text
citations_with_text.append(CitationWithText(text=""))
return DocumentAnalysisWithText(citations=citations_with_text)
@trace_method
def _build_final_response_dict(self, processed_results: List[Dict], query: str, question: str) -> Dict[str, Any]:
"""Build the final response dictionary from all processed results."""
# Build sources array
sources = []
total_snippets = 0
for result in processed_results:
source = {"url": result.get("url"), "title": result.get("title"), "description": result.get("description")}
if result.get("analysis") and result["analysis"].get("citations"):
analysis = result["analysis"]
source["citations"] = analysis["citations"]
total_snippets += len(analysis["citations"])
else:
source["citations"] = []
sources.append(source)
# Build final response structure
response = {
"query": query,
"question": question,
"total_sources": len(sources),
"total_citations": total_snippets,
"sources": sources,
}
if total_snippets == 0:
response["message"] = "No relevant passages found that directly answer the question."
return response
async def fetch_webpage(self, agent_state: "AgentState", url: str) -> str:
"""
Fetch a webpage and convert it to markdown/text format using trafilatura with readability fallback.
Args:
url: The URL of the webpage to fetch and convert
Returns:
String containing the webpage content in markdown/text format
"""
import asyncio
import html2text
import requests
from readability import Document
from trafilatura import extract, fetch_url
try:
# single thread pool call for the entire trafilatura pipeline
def trafilatura_pipeline():
downloaded = fetch_url(url) # fetch_url doesn't accept timeout parameter
if downloaded:
md = extract(downloaded, output_format="markdown")
return md
md = await asyncio.to_thread(trafilatura_pipeline)
if md:
return md
# single thread pool call for the entire fallback pipeline
def readability_pipeline():
response = requests.get(url, timeout=30, headers={"User-Agent": "Mozilla/5.0 (compatible; LettaBot/1.0)"})
response.raise_for_status()
doc = Document(response.text)
clean_html = doc.summary(html_partial=True)
return html2text.html2text(clean_html)
return await asyncio.to_thread(readability_pipeline)
except requests.exceptions.RequestException as e:
raise Exception(f"Error fetching webpage: {str(e)}")
except Exception as e:
raise Exception(f"Unexpected error: {str(e)}")