web search via exa (spec-015): web_search tool, sanitized results, per-user cap, host-config key

2026-07-14 12:08:48 +02:00
parent 5d01400638
commit cdd5a4cd48
6 changed files with 388 additions and 0 deletions
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+"""Web search tool via Exa (SPEC-015, FDB-022).
+
+A `web_search` function tool: the model looks things up on the open web
+when a general "look it up" question is not covered by IGDB, the codex,
+the news store, or a URL the user pasted. Results are external text, so
+titles and snippets are sanitized (SAF-03) before they reach the prompt.
+The Exa API key lives in host config (or the `EXA_API_KEY` env), never in
+the repo.
+"""
+
+import logging
+import os
+from typing import Any, Callable, Dict, List
+
+import aiohttp
+
+from .ai_responder import sanitize_external_text
+
+EXA_SEARCH_URL = "https://api.exa.ai/search"
+DEFAULT_RESULTS = 5
+MAX_RESULTS = 10
+DEFAULT_SNIPPET_CHARS = 400
+FETCH_TIMEOUT_S = 15
+
+WEB_SEARCH_TOOL = {
+    "name": "web_search",
+    "description": "Search the open web for current information when the user asks you to look something up and it is not "
+    "covered by game info (IGDB), the Codex, the news store, or a URL they pasted. Returns result titles, URLs, and a short "
+    "snippet; follow up with fetch_url on a result link for the full article.",
+    "parameters": {
+        "type": "object",
+        "properties": {
+            "query": {"type": "string", "description": "What to search the web for."},
+            "num_results": {"type": "integer", "description": "How many results to return (default 5, max 10)."},
+        },
+        "required": ["query"],
+    },
+}
+
+
+def _format_results(data: Any, snippet_chars: int) -> List[Dict[str, str]]:
+    """Reduce an Exa response to sanitized {title, url, snippet, published} rows (WEB-02)."""
+    results = data.get("results", []) if isinstance(data, dict) else []
+    out: List[Dict[str, str]] = []
+    for item in results:
+        if not isinstance(item, dict):
+            continue
+        out.append(
+            {
+                "title": sanitize_external_text(str(item.get("title") or ""), 200),
+                "url": str(item.get("url") or ""),
+                "snippet": sanitize_external_text(str(item.get("text") or item.get("snippet") or ""), snippet_chars),
+                "published": str(item.get("publishedDate") or ""),
+            }
+        )
+    return out
+
+
+class WebSearch:
+    def __init__(self, config_getter: Callable[[], Dict[str, Any]]) -> None:
+        self._config = config_getter
+
+    def _api_key(self) -> str:
+        return str(self._config().get("exa-api-key") or os.environ.get("EXA_API_KEY", ""))
+
+    def enabled(self) -> bool:
+        return bool(self._config().get("enable-web-search", False)) and bool(self._api_key())
+
+    async def _post(self, payload: Dict[str, Any], headers: Dict[str, str]) -> Any:
+        timeout = aiohttp.ClientTimeout(total=FETCH_TIMEOUT_S)
+        async with aiohttp.ClientSession(timeout=timeout) as session:
+            async with session.post(EXA_SEARCH_URL, json=payload, headers=headers) as response:
+                response.raise_for_status()
+                return await response.json()
+
+    async def search(self, query: str, num_results: int = DEFAULT_RESULTS) -> Dict[str, Any]:
+        """Return sanitized web results, or an error dict — never raise (WEB-04)."""
+        key = self._api_key()
+        if not key:
+            return {"error": "web search unavailable: no api key"}
+        query = (query or "").strip()
+        if not query:
+            return {"query": "", "results": []}
+        num = max(1, min(int(num_results or DEFAULT_RESULTS), MAX_RESULTS))  # WEB-03
+        snippet_chars = int(self._config().get("web-snippet-chars", DEFAULT_SNIPPET_CHARS))
+        payload = {"query": query, "numResults": num, "type": "auto", "contents": {"text": {"maxCharacters": max(snippet_chars, 200)}}}
+        headers = {"x-api-key": key, "Content-Type": "application/json"}
+        try:
+            data = await self._post(payload, headers)
+        except Exception as err:
+            logging.warning(f"web search failed: {err!r}")
+            return {"error": "web search failed"}
+        return {"query": query, "results": _format_results(data, snippet_chars)}