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hermes-agent/plugins/web/keyless_mcp.py

479 lines
20 KiB
Python

"""Keyless web search/extract via public free-tier endpoints (Exa, Parallel, Firecrawl, Keenable).
Resolved strictly LAST — after every keyed backend, the managed gateway, ddgs and
custom plugin providers — so it never pre-empts a deliberate setup. Privacy: no user
identifiers are sent; Parallel gets a random per-process ``session_id`` (rate
limiting only) and its optional ``model_name`` analytics field is deliberately
omitted. Disable the tier with ``web.keyless_fallback: false``.
"""
from __future__ import annotations
import json
import logging
import threading
import uuid
from typing import Any, Callable, Dict, List, Optional
from plugins.web._common import document as _page, search_fail, search_ok, web_hit as _row
logger = logging.getLogger(__name__)
EXA_MCP_URL = "https://mcp.exa.ai/mcp"
PARALLEL_MCP_URL = "https://search.parallel.ai/mcp"
KEENABLE_API_URL = "https://api.keenable.ai"
_KEENABLE_TITLE = "hermes-agent"
# Parallel free-tier rate-limit correlation id — random per process, never persisted.
_SESSION_ID = uuid.uuid4().hex
_TIMEOUT_SECONDS = 30
class KeylessMCPError(RuntimeError):
"""A keyless MCP call failed (transport, rate limit, or tool error)."""
_RATE_LIMIT_MARKERS = ("rate limit", "rate-limit", "ratelimit", "too many requests", "429", "quota exceeded", "slow down")
# vendor -> (display label, env key, signup URL) for the standard failure hint.
_VENDOR_HINTS = {
"exa": ("Exa", "EXA_API_KEY", "https://exa.ai"),
"parallel": ("Parallel", "PARALLEL_API_KEY", "https://parallel.ai"),
"firecrawl": ("Firecrawl", "FIRECRAWL_API_KEY", "https://firecrawl.dev"),
"keenable": ("Keenable", "KEENABLE_API_KEY", "https://keenable.ai"),
}
def _is_rate_limitish(message: str) -> bool:
"""Heuristic: does an error message look like free-tier throttling?"""
return any(marker in (message or "").lower() for marker in _RATE_LIMIT_MARKERS)
def _fail_msg(vendor: str, kind: str, exc: Any, *, other_backends: bool = True) -> str:
label, env_key, site = _VENDOR_HINTS[vendor]
alt = " or another web backend via `hermes tools`" if other_backends else ""
return f"Keyless {label} {kind} failed: {exc}. Set {env_key} ({site}){alt} for reliable service."
def _page_error(url: str, message: str) -> Dict[str, Any]:
return {"url": url, "title": "", "content": "", "error": message}
# --- Tier / config ------------------------------------------------------------
def keyless_enabled() -> bool:
"""True when the keyless tier is enabled. Delegates to the registry so the
``web.keyless_fallback`` (default on) chokepoint lives with backend resolution."""
try:
from agent.web_search_registry import _keyless_tier_enabled
return _keyless_tier_enabled()
except Exception as exc: # noqa: BLE001 — resolver optional in stripped envs
logger.debug("keyless_enabled(): registry helper unavailable: %s", exc)
return True
def provider_tier(name: str) -> str:
"""Return ``web.provider_tier.<name>`` (set by the ``hermes tools`` Free/Paid rows):
``free``, ``paid``, or ``auto`` for anything else including unset."""
try:
from hermes_cli.config import load_config
web_cfg = load_config().get("web") or {}
tiers = web_cfg.get("provider_tier") or {}
value = str(tiers.get(name, "") or "").lower().strip()
return value if value in ("free", "paid") else "auto"
except Exception as exc: # noqa: BLE001 — config layer optional
logger.debug("provider_tier(%r) config read failed: %s", name, exc)
return "auto"
def use_keyless(name: str, api_key: str) -> bool:
"""Single chokepoint for search + extract so tier semantics can't drift:
``free`` → keyless even with a key; ``paid`` → keyed even without one (the keyed
path raises its usual missing-key error); ``auto`` → keyless only when no key
and the tier is enabled."""
tier = provider_tier(name)
if tier == "free":
return True
if tier == "paid":
return False
return not api_key and keyless_enabled()
# --- MCP transport ------------------------------------------------------------
def _parse_mcp_body(body: str) -> str:
"""Extract the first text content item from an MCP tools/call response.
Handles plain-JSON bodies (Parallel) and SSE ``data: {...}`` lines (Exa). Raises
:class:`KeylessMCPError` for JSON-RPC errors and ``isError`` tool results (e.g.
Exa's free-tier rate-limit message).
"""
def _from_payload(payload: str) -> Optional[str]:
payload = payload.strip()
if not payload.startswith("{"):
return None
data = json.loads(payload)
err = data.get("error")
if err:
raise KeylessMCPError(str(err.get("message") or err))
result = data.get("result") or {}
content = result.get("content") or []
if result.get("isError"):
texts = [c.get("text", "") for c in content if isinstance(c, dict)]
raise KeylessMCPError(" ".join(t for t in texts if t) or "MCP tool call failed")
for item in content:
if isinstance(item, dict) and item.get("text"):
return str(item["text"])
return None
stripped = body.strip()
if stripped.startswith("{"):
try:
text = _from_payload(stripped)
if text is not None:
return text
except json.JSONDecodeError:
pass
for line in body.splitlines():
if not line.startswith("data: "):
continue
try:
text = _from_payload(line[len("data: "):])
except json.JSONDecodeError:
continue
if text is not None:
return text
raise KeylessMCPError("Unrecognized MCP response shape")
def mcp_call(url: str, tool: str, arguments: Dict[str, Any], timeout: int = _TIMEOUT_SECONDS) -> str:
"""POST a JSON-RPC ``tools/call`` to *url* and return the text payload.
Raises :class:`KeylessMCPError` on transport failures, non-2xx statuses,
JSON-RPC errors, and error-shaped tool results.
"""
import requests
payload = {"jsonrpc": "2.0", "id": 1, "method": "tools/call", "params": {"name": tool, "arguments": arguments}}
headers = {
"Content-Type": "application/json",
"Accept": "application/json, text/event-stream",
"User-Agent": "hermes-agent",
}
try:
response = requests.post(url, json=payload, headers=headers, timeout=timeout)
except requests.RequestException as exc:
raise KeylessMCPError(f"request failed: {exc}") from exc
if response.status_code >= 400:
raise KeylessMCPError(f"HTTP {response.status_code}: {response.text[:300]}")
return _parse_mcp_body(response.text)
# --- Parallel (search.parallel.ai) — JSON text payloads -----------------------
def parallel_search_keyless(query: str, limit: int = 5) -> Dict[str, Any]:
"""Keyless Parallel web search → legacy search response shape."""
try:
text = mcp_call(
PARALLEL_MCP_URL, "web_search",
{"objective": query, "search_queries": [query], "session_id": _SESSION_ID},
)
data = json.loads(text)
web_results = []
for i, result in enumerate(data.get("results") or []):
if limit and i >= limit:
break
web_results.append(_row(
result.get("url") or "", result.get("title") or "",
" ".join(result.get("excerpts") or []), i + 1,
))
return search_ok(web_results)
except KeylessMCPError as exc:
return search_fail(_fail_msg("parallel", "search", exc))
except (json.JSONDecodeError, TypeError, KeyError) as exc:
return search_fail(f"Keyless Parallel search returned an unexpected payload: {exc}")
def parallel_extract_keyless(urls: List[str]) -> List[Dict[str, Any]]:
"""Keyless Parallel web fetch → legacy extract result list."""
try:
text = mcp_call(
PARALLEL_MCP_URL, "web_fetch",
{"urls": list(urls), "objective": "Full page content", "session_id": _SESSION_ID},
)
data = json.loads(text)
except (KeylessMCPError, json.JSONDecodeError, TypeError) as exc:
message = _fail_msg("parallel", "extract", exc)
return [_page_error(u, message) for u in urls]
results: List[Dict[str, Any]] = []
seen = set()
for result in data.get("results") or []:
url = result.get("url") or ""
content = result.get("full_content") or result.get("content") or "\n\n".join(result.get("excerpts") or [])
seen.add(url)
results.append(_page(url, result.get("title") or "", content))
for error in data.get("errors") or []:
url = error.get("url") or ""
seen.add(url)
entry = _page_error(url, str(error.get("content") or error.get("error_type") or "extraction failed"))
entry["metadata"] = {"sourceURL": url}
results.append(entry)
# URLs the endpoint silently dropped still get an error entry (per-URL contract).
results.extend(_page_error(u, "no content returned") for u in urls if u not in seen)
return results
# --- Exa (mcp.exa.ai) — formatted plain-text payloads -------------------------
def _parse_exa_search_text(text: str, limit: int) -> List[Dict[str, Any]]:
"""Parse Exa's ``---``-separated ``Title:/URL:/Published:/Author:/Highlights:`` blocks."""
results: List[Dict[str, Any]] = []
for block in text.split("\n---\n"):
title = url = ""
highlight_lines: List[str] = []
in_highlights = False
for line in block.splitlines():
stripped = line.strip()
if stripped.startswith("Title:"):
title = stripped[len("Title:"):].strip()
in_highlights = False
elif stripped.startswith("URL:"):
url = stripped[len("URL:"):].strip()
in_highlights = False
elif stripped.startswith("Highlights:"):
in_highlights = True
elif stripped.startswith(("Published:", "Author:")):
in_highlights = False
elif in_highlights and stripped:
highlight_lines.append(stripped)
if url:
results.append(_row(url, title, " ".join(highlight_lines), len(results) + 1))
if limit and len(results) >= limit:
break
return results
def exa_search_keyless(query: str, limit: int = 5) -> Dict[str, Any]:
"""Keyless Exa web search → legacy search response shape."""
try:
text = mcp_call(EXA_MCP_URL, "web_search_exa", {"query": query, "numResults": max(1, int(limit))})
except KeylessMCPError as exc:
return search_fail(_fail_msg("exa", "search", exc))
return search_ok(_parse_exa_search_text(text, limit))
def exa_extract_keyless(urls: List[str]) -> List[Dict[str, Any]]:
"""Keyless Exa web fetch → legacy extract result list (called per-URL; the
tool returns one combined text payload)."""
results: List[Dict[str, Any]] = []
for url in urls:
try:
text = mcp_call(EXA_MCP_URL, "web_fetch_exa", {"urls": [url]})
except KeylessMCPError as exc:
results.append(_page_error(url, _fail_msg("exa", "extract", exc)))
continue
title = ""
for line in text.splitlines():
stripped = line.strip()
if stripped.startswith("# "):
title = stripped[2:].strip()
break
if stripped.startswith("Title:"):
title = stripped[len("Title:"):].strip()
break
results.append(_page(url, title, text))
return results
# --- Firecrawl keyless (public cloud API, no auth header) ---------------------
def firecrawl_search_keyless(query: str, limit: int = 5) -> Dict[str, Any]:
"""Keyless Firecrawl cloud search → legacy search response shape."""
from plugins.web.firecrawl.provider import _KeylessFirecrawlClient, _extract_web_search_results
try:
response = _KeylessFirecrawlClient().search(query=query, limit=limit)
return search_ok(_extract_web_search_results(response))
except Exception as exc: # noqa: BLE001 — normalized below
return search_fail(_fail_msg("firecrawl", "search", exc))
def firecrawl_extract_keyless(urls: List[str]) -> List[Dict[str, Any]]:
"""Keyless Firecrawl cloud scrape → legacy extract result list."""
from plugins.web.firecrawl.provider import _KeylessFirecrawlClient, _extract_scrape_payload
client = _KeylessFirecrawlClient()
results: List[Dict[str, Any]] = []
for url in urls:
try:
payload = _extract_scrape_payload(client.scrape(url=url, formats=["markdown"])) or {}
metadata = payload.get("metadata") or {}
if not isinstance(metadata, dict):
metadata = {}
content = payload.get("markdown") or payload.get("html") or ""
results.append(_page(url, metadata.get("title") or "", content))
except Exception as exc: # noqa: BLE001 — per-URL error entry
results.append(_page_error(url, _fail_msg("firecrawl", "extract", exc, other_backends=False)))
return results
# --- Keenable keyless (api.keenable.ai public endpoints) ----------------------
def _keenable_request(method: str, path: str, **kwargs: Any) -> Dict[str, Any]:
"""Call a Keenable public endpoint with the mandatory X-Keenable-Title app id."""
import requests
headers = {"X-Keenable-Title": _KEENABLE_TITLE}
if method == "post":
headers["Content-Type"] = "application/json"
response = getattr(requests, method)(f"{KEENABLE_API_URL}{path}", headers=headers, timeout=_TIMEOUT_SECONDS, **kwargs)
if response.status_code >= 400:
raise KeylessMCPError((response.text or "").strip() or f"HTTP {response.status_code}")
return response.json()
def keenable_search_keyless(query: str, limit: int = 5) -> Dict[str, Any]:
"""Keyless Keenable search (POST /v1/search/public) → legacy search response shape."""
try:
data = _keenable_request("post", "/v1/search/public", json={"query": query, "max_results": max(1, int(limit))})
except KeylessMCPError as exc:
return search_fail(_fail_msg("keenable", "search", exc))
except Exception as exc: # noqa: BLE001 — transport/JSON errors
return search_fail(f"Keyless Keenable search failed: {exc}.")
return search_ok([
_row(r.get("url") or "", r.get("title") or "", r.get("snippet") or r.get("description") or "", i + 1)
for i, r in enumerate(data.get("results") or [])
])
def keenable_extract_keyless(urls: List[str]) -> List[Dict[str, Any]]:
"""Keyless Keenable page fetch (GET /v1/fetch/public, per-URL) → legacy extract list."""
results: List[Dict[str, Any]] = []
for url in urls:
try:
data = _keenable_request("get", "/v1/fetch/public", params={"url": url})
results.append(_page(data.get("url") or url, data.get("title") or "", data.get("content") or "", source_url=url))
except Exception as exc: # noqa: BLE001 — per-URL error entry
results.append(_page_error(url, _fail_msg("keenable", "extract", exc, other_backends=False)))
return results
# --- Round-robin ring + next-in-line failover (rate-limited free tiers) -------
_KEYLESS_RING = ("exa", "parallel", "firecrawl", "keenable")
# Late-bound lookups (not bare references) so ``patch.object(keyless_mcp, "<vendor>_search_keyless")``
# is honored at call time. Tests also ``setitem`` these dicts directly.
_KEYLESS_SEARCHERS: Dict[str, Callable[[str, int], Dict[str, Any]]] = {
v: (lambda query, limit, _v=v: globals()[f"{_v}_search_keyless"](query, limit)) for v in _KEYLESS_RING
}
_KEYLESS_EXTRACTORS: Dict[str, Callable[[List[str]], List[Dict[str, Any]]]] = {
v: (lambda urls, _v=v: globals()[f"{_v}_extract_keyless"](urls)) for v in _KEYLESS_RING
}
# Per-process round-robin cursor, seeded by the random session id so the fleet
# spreads across vendors; advances once per unpinned keyless request.
_ring_lock = threading.Lock()
_ring_cursor = int(_SESSION_ID, 16) % len(_KEYLESS_RING)
def _vendor_pinned(name: str) -> bool:
"""True when config explicitly routes web traffic to *name* (backend keys or a
``free`` tier pin). A pinned vendor starts every keyless request."""
if provider_tier(name) == "free":
return True
try:
import tools.web_tools as _wt
web_cfg = _wt._load_web_config()
return any(
(web_cfg.get(key) or "").lower().strip() == name
for key in ("backend", "search_backend", "extract_backend")
)
except Exception as exc: # noqa: BLE001 — config layer optional
logger.debug("_vendor_pinned(%r) config read failed: %s", name, exc)
return False
def _ring_order(name: str) -> List[str]:
"""Vendor walk order: pinned → start at *name* (its ring position fixes the
failover succession); else round-robin from the cursor, advancing it per request.
Vendors pinned ``paid`` are excluded (explicit paid opts their free endpoint out)."""
global _ring_cursor
if _vendor_pinned(name):
start = _KEYLESS_RING.index(name) if name in _KEYLESS_RING else 0
else:
with _ring_lock:
start = _ring_cursor
_ring_cursor = (_ring_cursor + 1) % len(_KEYLESS_RING)
ordered = _KEYLESS_RING[start:] + _KEYLESS_RING[:start]
return [v for v in ordered if provider_tier(v) != "paid"]
_ALL_PAID_MSG = "All keyless web providers are pinned to paid tiers."
def _walk_ring(name: str, kind: str, call, throttled) -> tuple:
"""Shared ring walk: call each vendor from :func:`_ring_order` until a result is
not ``throttled``. Returns ``(order, vendor, result, exhausted)``; ``order`` is
empty (and result None) when every vendor is pinned paid."""
order = _ring_order(name)
vendor = None
result: Any = None
for i, vendor in enumerate(order):
result = call(vendor)
if not throttled(result):
return order, vendor, result, False
if i + 1 < len(order):
logger.info("keyless %s %s throttled; failing over to %s", vendor, kind, order[i + 1])
return order, vendor, result, True
def search_with_failover(name: str, query: str, limit: int = 5) -> Dict[str, Any]:
"""Keyless search across the ring; rate-limit-shaped errors advance to the
next vendor, other errors stop the walk (a malformed query fails everywhere).
``data.served_by`` is set when the serving vendor differs from *name*."""
def _throttled(result: Dict[str, Any]) -> bool:
return not result.get("success") and _is_rate_limitish(result.get("error", ""))
order, vendor, result, exhausted = _walk_ring(
name, "search", lambda v: _KEYLESS_SEARCHERS[v](query, limit), _throttled
)
if not order:
return search_fail(_ALL_PAID_MSG)
if exhausted:
result["error"] = f"{result.get('error', '')} (all keyless vendors throttled: {', '.join(order)})"
elif result.get("success") and vendor != name:
result.setdefault("data", {})["served_by"] = vendor
return result
def extract_with_failover(name: str, urls: List[str]) -> List[Dict[str, Any]]:
"""Keyless extract across the ring; fails over only when EVERY url in a batch
is rate-limit-shaped (partial failures are page problems, returned as-is)."""
def _all_throttled(results: List[Dict[str, Any]]) -> bool:
errors = [r.get("error", "") for r in results]
return bool(results) and all(e and _is_rate_limitish(e) for e in errors)
order, _vendor, results, _exhausted = _walk_ring(
name, "extract", lambda v: _KEYLESS_EXTRACTORS[v](list(urls)), _all_throttled
)
if not order:
return [_page_error(u, _ALL_PAID_MSG) for u in urls]
return results