chore(llm): one-shot OpenRouter free-tier reachability probe

scripts/diagnose_openrouter.py

@@ -0,0 +1,79 @@
+"""Probe OpenRouter for which free-tier model IDs are reachable today.
+
+Reads OPENROUTER_API_KEY from .env (or process env). Issues a single
+8-token chat completion against a candidate list and prints one line per
+model: status (OK / HTTP-code / exception name) + a 30-char preview of
+the response when OK.
+
+Use:
+    python scripts/diagnose_openrouter.py
+
+Or to probe a custom list:
+    python scripts/diagnose_openrouter.py google/gemma-2-9b-it:free meta-llama/llama-3.2-3b-instruct:free
+"""
+from __future__ import annotations
+
+import os
+import sys
+from pathlib import Path
+
+# Manually parse .env without python-dotenv (some envs choke on its
+# frame-introspection in heredocs / non-stack-rooted callers).
+_env_path = Path(__file__).resolve().parent.parent / ".env"
+if _env_path.exists():
+    for raw in _env_path.read_text().splitlines():
+        s = raw.strip()
+        if not s or s.startswith("#") or "=" not in s:
+            continue
+        k, v = s.split("=", 1)
+        os.environ.setdefault(k.strip(), v.strip())
+
+if not os.environ.get("OPENROUTER_API_KEY"):
+    sys.exit("OPENROUTER_API_KEY not set (looked in env and .env)")
+
+# Candidate list: well-known stable free-tier IDs as of 2026-Q2.
+# Update by replacing this list — script is a probe, not a config source.
+DEFAULT_CANDIDATES = [
+    "google/gemma-2-9b-it:free",
+    "google/gemini-2.0-flash-exp:free",
+    "meta-llama/llama-3.2-3b-instruct:free",
+    "meta-llama/llama-3.3-70b-instruct:free",
+    "mistralai/mistral-7b-instruct:free",
+    "qwen/qwen-2.5-72b-instruct:free",
+    "deepseek/deepseek-r1:free",
+    "deepseek/deepseek-chat:free",
+    "nousresearch/hermes-3-llama-3.1-405b:free",
+    "microsoft/phi-3-mini-128k-instruct:free",
+]
+
+candidates = sys.argv[1:] or DEFAULT_CANDIDATES
+
+from openai import (  # noqa: E402  (after env load)
+    OpenAI, APIStatusError, APIConnectionError, RateLimitError, APITimeoutError,
+)
+
+client = OpenAI(
+    base_url="https://openrouter.ai/api/v1",
+    api_key=os.environ["OPENROUTER_API_KEY"],
+    timeout=15.0,
+)
+
+for m in candidates:
+    try:
+        c = client.chat.completions.create(
+            model=m,
+            messages=[{"role": "user", "content": "Reply with the single word OK."}],
+            max_tokens=8,
+            temperature=0,
+        )
+        text = (c.choices[0].message.content or "").strip()
+        print(f"  OK     {m}  →  {text[:30]!r}")
+    except APIStatusError as e:
+        code = getattr(e, "status_code", "?")
+        print(f"  {code:<5}  {m}")
+    except RateLimitError:
+        print(f"  429    {m}  (rate-limited)")
+    except (APIConnectionError, APITimeoutError) as e:
+        print(f"  CONN   {m}  ({type(e).__name__})")
+    except Exception as e:
+        print(f"  ERR    {m}  ({type(e).__name__}: {e})")