Files
hermes-agent/tools/session_search_tool.py
T
yoniebans 3ac750ec07 refactor(session_search): default to summary mode, document fast as opt-in
Reverses the default introduced by the salvaged dual-mode commit.

Why: profiled four representative queries against a real 280-session
state.db (workspace harness, not committed). Summary mode is 1,299x-6,293x
slower than fast (median ~30s vs ~10ms; 99%+ in the auxiliary LLM call) and
produces 2.9x-3.9x larger result blobs, but it answers a materially different
question. The user's typical 'what did we work on for X?' is the summary
question — fast surfaces only what FTS5 directly matched while summary
surfaces cross-session synthesis (e.g. work sessions referenced inside
the matched cron jobs). Backwards-compatible default; fast remains
opt-in for cheap discovery via mode='fast'.

Changes:
- tools/session_search_tool.py: default parameter, defensive coercion
  fallbacks, and registry handler all default to 'summary'. Schema
  description rewritten with measured trade-offs and the 'use fast for
  discovery, summary for recall' framing.
- run_agent.py: both direct call sites mirror the new default.
- tests/tools/test_session_search.py: split the old default-test into
  test_default_search_returns_summary_mode_recap (asserts new default)
  and test_explicit_fast_mode_returns_snippets... (covers fast path
  without mocking the default away). Invalid-mode test now asserts
  fallback to summary. Source-grep test updated.
2026-05-11 22:32:04 +02:00

672 lines
28 KiB
Python

#!/usr/bin/env python3
"""
Session Search Tool - Long-Term Conversation Recall
Searches past session transcripts in SQLite via FTS5. Keyword search defaults
to fast snippet/context hits without any LLM call; callers can opt into focused
LLM summaries with mode="summary" when deeper recall is worth the latency.
Flow:
1. FTS5 search finds matching messages ranked by relevance
2. Groups by session, takes the top N unique sessions (default 3)
3. Fast mode returns snippets and nearby context immediately
4. Summary mode loads each session, truncates around matches, and calls an LLM
5. Returns per-session hits/summaries with metadata
"""
import asyncio
import concurrent.futures
import json
import logging
import re
from typing import Dict, Any, List, Optional, Union
from agent.auxiliary_client import async_call_llm, extract_content_or_reasoning
MAX_SESSION_CHARS = 100_000
MAX_SUMMARY_TOKENS = 10000
def _get_session_search_max_concurrency(default: int = 3) -> int:
"""Read auxiliary.session_search.max_concurrency with sane bounds."""
try:
from hermes_cli.config import load_config
config = load_config()
except ImportError:
return default
aux = config.get("auxiliary", {}) if isinstance(config, dict) else {}
task_config = aux.get("session_search", {}) if isinstance(aux, dict) else {}
if not isinstance(task_config, dict):
return default
raw = task_config.get("max_concurrency")
if raw is None:
return default
try:
value = int(raw)
except (TypeError, ValueError):
return default
return max(1, min(value, 5))
def _format_timestamp(ts: Union[int, float, str, None]) -> str:
"""Convert a Unix timestamp (float/int) or ISO string to a human-readable date.
Returns "unknown" for None, str(ts) if conversion fails.
"""
if ts is None:
return "unknown"
try:
if isinstance(ts, (int, float)):
from datetime import datetime
dt = datetime.fromtimestamp(ts)
return dt.strftime("%B %d, %Y at %I:%M %p")
if isinstance(ts, str):
if ts.replace(".", "").replace("-", "").isdigit():
from datetime import datetime
dt = datetime.fromtimestamp(float(ts))
return dt.strftime("%B %d, %Y at %I:%M %p")
return ts
except (ValueError, OSError, OverflowError) as e:
# Log specific errors for debugging while gracefully handling edge cases
logging.debug("Failed to format timestamp %s: %s", ts, e, exc_info=True)
except Exception as e:
logging.debug("Unexpected error formatting timestamp %s: %s", ts, e, exc_info=True)
return str(ts)
def _format_conversation(messages: List[Dict[str, Any]]) -> str:
"""Format session messages into a readable transcript for summarization."""
parts = []
for msg in messages:
role = msg.get("role", "unknown").upper()
content = msg.get("content") or ""
tool_name = msg.get("tool_name")
if role == "TOOL" and tool_name:
# Truncate long tool outputs
if len(content) > 500:
content = content[:250] + "\n...[truncated]...\n" + content[-250:]
parts.append(f"[TOOL:{tool_name}]: {content}")
elif role == "ASSISTANT":
# Include tool call names if present
tool_calls = msg.get("tool_calls")
if tool_calls and isinstance(tool_calls, list):
tc_names = []
for tc in tool_calls:
if isinstance(tc, dict):
name = tc.get("name") or tc.get("function", {}).get("name", "?")
tc_names.append(name)
if tc_names:
parts.append(f"[ASSISTANT]: [Called: {', '.join(tc_names)}]")
if content:
parts.append(f"[ASSISTANT]: {content}")
else:
parts.append(f"[ASSISTANT]: {content}")
else:
parts.append(f"[{role}]: {content}")
return "\n\n".join(parts)
def _truncate_around_matches(
full_text: str, query: str, max_chars: int = MAX_SESSION_CHARS
) -> str:
"""
Truncate a conversation transcript to *max_chars*, choosing a window
that maximises coverage of positions where the *query* actually appears.
Strategy (in priority order):
1. Try to find the full query as a phrase (case-insensitive).
2. If no phrase hit, look for positions where all query terms appear
within a 200-char proximity window (co-occurrence).
3. Fall back to individual term positions.
Once candidate positions are collected the function picks the window
start that covers the most of them.
"""
if len(full_text) <= max_chars:
return full_text
text_lower = full_text.lower()
query_lower = query.lower().strip()
match_positions: list[int] = []
# --- 1. Full-phrase search ------------------------------------------------
phrase_pat = re.compile(re.escape(query_lower))
match_positions = [m.start() for m in phrase_pat.finditer(text_lower)]
# --- 2. Proximity co-occurrence of all terms (within 200 chars) -----------
if not match_positions:
terms = query_lower.split()
if len(terms) > 1:
# Collect every occurrence of each term
term_positions: dict[str, list[int]] = {}
for t in terms:
term_positions[t] = [
m.start() for m in re.finditer(re.escape(t), text_lower)
]
# Slide through positions of the rarest term and check proximity
rarest = min(terms, key=lambda t: len(term_positions.get(t, [])))
for pos in term_positions.get(rarest, []):
if all(
any(abs(p - pos) < 200 for p in term_positions.get(t, []))
for t in terms
if t != rarest
):
match_positions.append(pos)
# --- 3. Individual term positions (last resort) ---------------------------
if not match_positions:
terms = query_lower.split()
for t in terms:
for m in re.finditer(re.escape(t), text_lower):
match_positions.append(m.start())
if not match_positions:
# Nothing at all — take from the start
truncated = full_text[:max_chars]
suffix = "\n\n...[later conversation truncated]..." if max_chars < len(full_text) else ""
return truncated + suffix
# --- Pick window that covers the most match positions ---------------------
match_positions.sort()
best_start = 0
best_count = 0
for candidate in match_positions:
ws = max(0, candidate - max_chars // 4) # bias: 25% before, 75% after
we = ws + max_chars
if we > len(full_text):
ws = max(0, len(full_text) - max_chars)
we = len(full_text)
count = sum(1 for p in match_positions if ws <= p < we)
if count > best_count:
best_count = count
best_start = ws
start = best_start
end = min(len(full_text), start + max_chars)
truncated = full_text[start:end]
prefix = "...[earlier conversation truncated]...\n\n" if start > 0 else ""
suffix = "\n\n...[later conversation truncated]..." if end < len(full_text) else ""
return prefix + truncated + suffix
async def _summarize_session(
conversation_text: str, query: str, session_meta: Dict[str, Any]
) -> Optional[str]:
"""Summarize a single session conversation focused on the search query."""
system_prompt = (
"You are reviewing a past conversation transcript to help recall what happened. "
"Summarize the conversation with a focus on the search topic. Include:\n"
"1. What the user asked about or wanted to accomplish\n"
"2. What actions were taken and what the outcomes were\n"
"3. Key decisions, solutions found, or conclusions reached\n"
"4. Any specific commands, files, URLs, or technical details that were important\n"
"5. Anything left unresolved or notable\n\n"
"Be thorough but concise. Preserve specific details (commands, paths, error messages) "
"that would be useful to recall. Write in past tense as a factual recap."
)
source = session_meta.get("source", "unknown")
started = _format_timestamp(session_meta.get("started_at"))
user_prompt = (
f"Search topic: {query}\n"
f"Session source: {source}\n"
f"Session date: {started}\n\n"
f"CONVERSATION TRANSCRIPT:\n{conversation_text}\n\n"
f"Summarize this conversation with focus on: {query}"
)
max_retries = 3
for attempt in range(max_retries):
try:
response = await async_call_llm(
task="session_search",
messages=[
{"role": "system", "content": system_prompt},
{"role": "user", "content": user_prompt},
],
temperature=0.1,
max_tokens=MAX_SUMMARY_TOKENS,
)
content = extract_content_or_reasoning(response)
if content:
return content
# Reasoning-only / empty — let the retry loop handle it
logging.warning("Session search LLM returned empty content (attempt %d/%d)", attempt + 1, max_retries)
if attempt < max_retries - 1:
await asyncio.sleep(1 * (attempt + 1))
continue
return content
except RuntimeError:
logging.warning("No auxiliary model available for session summarization")
return None
except Exception as e:
if attempt < max_retries - 1:
await asyncio.sleep(1 * (attempt + 1))
else:
logging.warning(
"Session summarization failed after %d attempts: %s",
max_retries,
e,
exc_info=True,
)
return None
# Sources that are excluded from session browsing/searching by default.
# Third-party integrations (Paperclip agents, etc.) tag their sessions with
# HERMES_SESSION_SOURCE=tool so they don't clutter the user's session history.
_HIDDEN_SESSION_SOURCES = ("tool",)
def _list_recent_sessions(db, limit: int, current_session_id: str = None) -> str:
"""Return metadata for the most recent sessions (no LLM calls)."""
try:
sessions = db.list_sessions_rich(
limit=limit + 5,
exclude_sources=list(_HIDDEN_SESSION_SOURCES),
order_by_last_active=True,
) # fetch extra to skip current
# Resolve current session lineage to exclude it
current_root = None
if current_session_id:
try:
sid = current_session_id
visited = set()
current_root = current_session_id
while sid and sid not in visited:
visited.add(sid)
current_root = sid
s = db.get_session(sid)
parent = s.get("parent_session_id") if s else None
sid = parent if parent else None
except Exception:
current_root = current_session_id
results = []
for s in sessions:
sid = s.get("id", "")
if current_root and (sid == current_root or sid == current_session_id):
continue
# Skip child/delegation sessions (they have parent_session_id)
if s.get("parent_session_id"):
continue
results.append({
"session_id": sid,
"title": s.get("title") or None,
"source": s.get("source", ""),
"started_at": s.get("started_at", ""),
"last_active": s.get("last_active", ""),
"message_count": s.get("message_count", 0),
"preview": s.get("preview", ""),
})
if len(results) >= limit:
break
return json.dumps({
"success": True,
"mode": "recent",
"results": results,
"count": len(results),
"message": f"Showing {len(results)} most recent sessions. Use a keyword query to search specific topics.",
}, ensure_ascii=False)
except Exception as e:
logging.error("Error listing recent sessions: %s", e, exc_info=True)
return tool_error(f"Failed to list recent sessions: {e}", success=False)
def session_search(
query: str,
role_filter: str = None,
limit: int = 3,
db=None,
current_session_id: str = None,
mode: str = "summary",
) -> str:
"""
Search past sessions. Summary mode (default) returns LLM-generated recaps;
fast mode returns FTS snippets without LLM calls for cheap discovery.
"""
if db is None:
try:
from hermes_state import SessionDB
db = SessionDB()
except Exception:
logging.debug("SessionDB unavailable for session_search", exc_info=True)
from hermes_state import format_session_db_unavailable
return tool_error(format_session_db_unavailable(), success=False)
mode = (mode or "summary").strip().lower() if isinstance(mode, str) else "summary"
if mode in ("summarized", "summarise", "summarize", "deep"):
mode = "summary"
if mode not in ("fast", "summary"):
mode = "summary"
# Defensive: models (especially open-source) may send non-int limit values
# (None when JSON null, string "int", or even a type object). Coerce to a
# safe integer before any arithmetic/comparison to prevent TypeError.
if not isinstance(limit, int):
try:
limit = int(limit)
except (TypeError, ValueError):
limit = 3
limit = max(1, min(limit, 5)) # Clamp to [1, 5]
# Recent sessions mode: when query is empty, return metadata for recent sessions.
# No LLM calls — just DB queries for titles, previews, timestamps.
if not query or not query.strip():
return _list_recent_sessions(db, limit, current_session_id)
query = query.strip()
try:
# Parse role filter
role_list = None
if role_filter and role_filter.strip():
role_list = [r.strip() for r in role_filter.split(",") if r.strip()]
# FTS5 search -- get matches ranked by relevance
raw_results = db.search_messages(
query=query,
role_filter=role_list,
exclude_sources=list(_HIDDEN_SESSION_SOURCES),
limit=50, # Get more matches to find unique sessions
offset=0,
)
if not raw_results:
return json.dumps({
"success": True,
"mode": mode,
"query": query,
"results": [],
"count": 0,
"message": "No matching sessions found.",
}, ensure_ascii=False)
# Resolve child sessions to their parent — delegation stores detailed
# content in child sessions, but the user's conversation is the parent.
def _resolve_to_parent(session_id: str) -> str:
"""Walk delegation chain to find the root parent session ID."""
visited = set()
sid = session_id
while sid and sid not in visited:
visited.add(sid)
try:
session = db.get_session(sid)
if not session:
break
parent = session.get("parent_session_id")
if parent:
sid = parent
else:
break
except Exception as e:
logging.debug(
"Error resolving parent for session %s: %s",
sid,
e,
exc_info=True,
)
break
return sid
current_lineage_root = (
_resolve_to_parent(current_session_id) if current_session_id else None
)
# Group by resolved (parent) session_id, dedup, skip the current
# session lineage. Compression and delegation create child sessions
# that still belong to the same active conversation.
seen_sessions = {}
for result in raw_results:
raw_sid = result["session_id"]
resolved_sid = _resolve_to_parent(raw_sid)
# Skip the current session lineage — the agent already has that
# context, even if older turns live in parent fragments.
if current_lineage_root and resolved_sid == current_lineage_root:
continue
if current_session_id and raw_sid == current_session_id:
continue
if resolved_sid not in seen_sessions:
result = dict(result)
result["session_id"] = resolved_sid
seen_sessions[resolved_sid] = result
if len(seen_sessions) >= limit:
break
if mode == "fast":
results = []
for session_id, match_info in seen_sessions.items():
try:
session_meta = db.get_session(session_id) or {}
except Exception:
session_meta = {}
snippet = match_info.get("snippet") or ""
context = match_info.get("context") or []
if not isinstance(context, list):
context = []
results.append({
"session_id": session_id,
"when": _format_timestamp(
session_meta.get("started_at") or match_info.get("session_started")
),
"source": session_meta.get("source") or match_info.get("source", "unknown"),
"model": session_meta.get("model") or match_info.get("model") or "unknown",
"matched_role": match_info.get("role"),
"title": session_meta.get("title") or None,
"snippet": snippet,
"context": context,
"summary": "[Search hit — summary not generated in fast mode] Use snippet/context fields, or set mode='summary' for LLM-generated recall.",
})
return json.dumps({
"success": True,
"mode": "fast",
"query": query,
"results": results,
"count": len(results),
"sessions_searched": len(seen_sessions),
"message": "Fast search returned FTS snippets without LLM summarization. Use mode='summary' for focused summaries when needed.",
}, ensure_ascii=False)
# Prepare all sessions for parallel summarization
tasks = []
for session_id, match_info in seen_sessions.items():
try:
messages = db.get_messages_as_conversation(session_id)
if not messages:
continue
session_meta = db.get_session(session_id) or {}
conversation_text = _format_conversation(messages)
conversation_text = _truncate_around_matches(conversation_text, query)
tasks.append((session_id, match_info, conversation_text, session_meta))
except Exception as e:
logging.warning(
"Failed to prepare session %s: %s",
session_id,
e,
exc_info=True,
)
# Summarize all sessions in parallel
async def _summarize_all() -> List[Union[str, Exception]]:
"""Summarize all sessions with bounded concurrency."""
max_concurrency = min(_get_session_search_max_concurrency(), max(1, len(tasks)))
semaphore = asyncio.Semaphore(max_concurrency)
async def _bounded_summary(text: str, meta: Dict[str, Any]) -> Optional[str]:
async with semaphore:
return await _summarize_session(text, query, meta)
coros = [
_bounded_summary(text, meta)
for _, _, text, meta in tasks
]
return await asyncio.gather(*coros, return_exceptions=True)
try:
# Use _run_async() which properly manages event loops across
# CLI, gateway, and worker-thread contexts. The previous
# pattern (asyncio.run() in a ThreadPoolExecutor) created a
# disposable event loop that conflicted with cached
# AsyncOpenAI/httpx clients bound to a different loop,
# causing deadlocks in gateway mode (#2681).
from model_tools import _run_async
results = _run_async(_summarize_all())
except concurrent.futures.TimeoutError:
logging.warning(
"Session summarization timed out after 60 seconds",
exc_info=True,
)
return json.dumps({
"success": False,
"error": "Session summarization timed out. Try a more specific query or reduce the limit.",
}, ensure_ascii=False)
summaries = []
for (session_id, match_info, conversation_text, session_meta), result in zip(tasks, results):
if isinstance(result, Exception):
logging.warning(
"Failed to summarize session %s: %s",
session_id, result, exc_info=True,
)
result = None
# Prefer resolved parent session metadata over FTS5 match metadata.
# match_info carries source/model from the *child* session that contained
# the FTS5 hit; after _resolve_to_parent() the session_id points to the
# root, so session_meta has the authoritative platform/source for the
# session the user actually cares about (#15909).
entry = {
"session_id": session_id,
"when": _format_timestamp(
session_meta.get("started_at") or match_info.get("session_started")
),
"source": session_meta.get("source") or match_info.get("source", "unknown"),
"model": session_meta.get("model") or match_info.get("model"),
}
if result:
entry["summary"] = result
else:
# Fallback: raw preview so matched sessions aren't silently
# dropped when the summarizer is unavailable (fixes #3409).
preview = (conversation_text[:500] + "\n…[truncated]") if conversation_text else "No preview available."
entry["summary"] = f"[Raw preview — summarization unavailable]\n{preview}"
summaries.append(entry)
return json.dumps({
"success": True,
"mode": "summary",
"query": query,
"results": summaries,
"count": len(summaries),
"sessions_searched": len(seen_sessions),
}, ensure_ascii=False)
except Exception as e:
logging.error("Session search failed: %s", e, exc_info=True)
return tool_error(f"Search failed: {str(e)}", success=False)
def check_session_search_requirements() -> bool:
"""Requires SQLite state database; summary mode also needs an auxiliary model."""
try:
from hermes_state import DEFAULT_DB_PATH
return DEFAULT_DB_PATH.parent.exists()
except ImportError:
return False
SESSION_SEARCH_SCHEMA = {
"name": "session_search",
"description": (
"Search your long-term memory of past conversations, or browse recent sessions. This is your recall -- "
"every past session is searchable.\n\n"
"TWO MODES:\n"
"1. Recent sessions (no query): Call with no arguments to see what was worked on recently. "
"Returns titles, previews, and timestamps. Zero LLM cost, instant. "
"Start here when the user asks what were we working on or what did we do recently.\n"
"2. Keyword search (with query): Search for specific topics across all past sessions. "
"Defaults to mode='summary', returning LLM-generated recaps of the matched sessions (the recall "
"you usually want). Set mode='fast' for cheap, instant FTS snippet hits when you only need to "
"discover which sessions touched a topic.\n\n"
"USE THIS PROACTIVELY when:\n"
"- The user says 'we did this before', 'remember when', 'last time', 'as I mentioned'\n"
"- The user asks about a topic you worked on before but don't have in current context\n"
"- The user references a project, person, or concept that seems familiar but isn't in memory\n"
"- You want to check if you've solved a similar problem before\n"
"- The user asks 'what did we do about X?' or 'how did we fix Y?'\n\n"
"Don't hesitate to search when it is actually cross-session -- summary mode is one tool call away. "
"Better to search and confirm than to guess or ask the user to repeat themselves.\n\n"
"Search syntax: keywords joined with OR for broad recall (elevenlabs OR baseten OR funding), "
"phrases for exact match (\"docker networking\"), boolean (python NOT java), prefix (deploy*). "
"IMPORTANT: Use OR between keywords for best results — FTS5 defaults to AND which misses "
"sessions that only mention some terms. If a broad OR query returns nothing, try individual "
"keyword searches in parallel."
),
"parameters": {
"type": "object",
"properties": {
"query": {
"type": "string",
"description": "Search query — keywords, phrases, or boolean expressions to find in past sessions. Omit this parameter entirely to browse recent sessions instead (returns titles, previews, timestamps with no LLM cost).",
},
"role_filter": {
"type": "string",
"description": "Optional: only search messages from specific roles (comma-separated). E.g. 'user,assistant' to skip tool outputs.",
},
"limit": {
"type": "integer",
"description": "Max sessions to return (default: 3, max: 5).",
"default": 3,
},
"mode": {
"type": "string",
"enum": ["fast", "summary"],
"description": (
"summary (default) loads each matched session's transcript and runs the LLM "
"summariser to produce a focused recap — ~30s, ~3-4 KB returned per session, "
"surfaces cross-session synthesis (e.g. references to work sessions that didn't "
"themselves match FTS5). Use this when the user wants to know WHAT HAPPENED in "
"past sessions about a topic. "
"fast returns FTS5 snippets + 1-message context without any LLM call — ~10ms, "
"~1 KB per session, surfaces only what FTS5 directly matched. Use this when the "
"user only needs to discover WHICH SESSIONS touched a topic, or when you'll "
"drill into specific sessions yourself afterwards. "
"If a fast result looks promising but lacks detail, you can call again with "
"mode='summary' on the same query."
),
"default": "summary",
},
},
"required": [],
},
}
# --- Registry ---
from tools.registry import registry, tool_error
registry.register(
name="session_search",
toolset="session_search",
schema=SESSION_SEARCH_SCHEMA,
handler=lambda args, **kw: session_search(
query=args.get("query") or "",
role_filter=args.get("role_filter"),
limit=args.get("limit", 3),
mode=args.get("mode", "summary"),
db=kw.get("db"),
current_session_id=kw.get("current_session_id")),
check_fn=check_session_search_requirements,
emoji="🔍",
)