Implement common SDK patterns for OpenRouter integration. Use when building production applications. Trigger with phrases like 'openrouter sdk', 'openrouter client pattern', 'openrouter best practices', 'openrouter code patterns'.
Build production-grade OpenRouter client wrappers using the OpenAI SDK. The OpenAI Python/TypeScript SDKs work natively with OpenRouter by changing base_url to https://openrouter.ai/api/v1. This skill covers typed wrappers, retry strategies, middleware, and reusable patterns.
Prerequisites
An OpenRouter API key (sk-or-v1-...) exported as OPENROUTER_API_KEY — see the openrouter-install-auth skill for setup
Python 3.8+ with the OpenAI SDK plus requests (used for the /auth/key credits check and /generation cost lookups), or Node.js 18+ with the OpenAI SDK
Optional: tenacity if you want the custom retry decorator beyond the SDK's built-in backoff
An app name and URL to send as HTTP-Referer / X-Title default headers for dashboard attribution
Instructions
Start from the Python: Production Client Wrapper (or the TypeScript variant): point the OpenAI SDK at base_url="https://openrouter.ai/api/v1", read OPENROUTER_API_KEY from the environment, and set the HTTP-Referer / X-Title default headers in the constructor.
Return typed results from every call — the CompletionResult dataclass/interface captures content, the served model, prompt_tokens/completion_tokens, generation_id, and latency_ms.
Tune the SDK's built-in retries per the Retry Strategy section (max_retries, timeout in the constructor); add the tenacity decorator only when you need retry behavior beyond the SDK's 429/5xx/connection handling.
Layer cross-cutting concerns via the Middleware Pattern — with_cost_tracking queries GET /api/v1/generation?id= after each request and accumulates a session cost total.
Surface remaining credits and rate limits with check_credits(), which calls GET /api/v1/auth/key with the same key.
Map SDK exceptions using the Error Handling table, then apply the Enterprise Considerations (single central wrapper, dependency injection for tests, SLA-based max_retries).
Python: Production Client Wrapper
import os, time, hashlib, json, logging
from dataclasses import dataclass
from typing import Optional
from openai import OpenAI, APIError, RateLimitError, APITimeoutError
log = logging.getLogger("openrouter")
@dataclass
class CompletionResult:
content: str
model: str
prompt_tokens: int
completion_tokens: int
generation_id: str
latency_ms: float
class OpenRouterClient:
def __init__(
self,
api_key: Optional[str] = None,
app_name: str = "my-app",
app_url: str = "https://my-app.com",
max_retries: int = 3,
timeout: float = 60.0,
):
self.client = OpenAI(
base_url="https://openrouter.ai/api/v1",
api_key=api_key or os.environ["OPENROUTER_API_KEY"],
max_retries=max_retries, # Built-in SDK retry with backoff
timeout=timeout,
default_headers={
"HTTP-Referer": app_url,
"X-Title": app_name,
},
)
self._cache: dict[str, CompletionResult] = {}
def complete(
self,
prompt: str,
model: str = "anthropic/claude-3.5-sonnet",
system: str = "",
max_tokens: int = 1024,
temperature: float = 0.7,
cache: bool = False,
**extra_params,
) -> CompletionResult:
messages = []
if system:
messages.append({"role": "system", "content": system})
messages.append({"role": "user", "content": prompt})
# Optional caching (deterministic requests only)
cache_key = None
if cache and temperature == 0:
cache_key = hashlib.sha256(
json.dumps({"model": model, "messages": messages, "max_tokens": max_tokens}).encode()
).hexdigest()
if cache_key in self._cache:
log.debug(f"Cache hit: {cache_key[:12]}")
return self._cache[cache_key]
start = time.monotonic()
response = self.client.chat.completions.create(
model=model,
messages=messages,
max_tokens=max_tokens,
temperature=temperature,
**extra_params,
)
latency = (time.monotonic() - start) * 1000
result = CompletionResult(
content=response.choices[0].message.content or "",
model=response.model,
prompt_tokens=response.usage.prompt_tokens,
completion_tokens=response.usage.completion_tokens,
generation_id=response.id,
latency_ms=round(latency, 1),
)
log.info(f"[{result.model}] {result.prompt_tokens}+{result.completion_tokens} tokens, {result.latency_ms}ms")
if cache_key:
self._cache[cache_key] = result
return result
def check_credits(self) -> dict:
"""Check remaining credits and rate limits."""
import requests
resp = requests.get(
"https://openrouter.ai/api/v1/auth/key",
headers={"Authorization": f"Bearer {self.client.api_key}"},
)
return resp.json()["data"]
# Usage
or_client = OpenRouterClient(app_name="my-saas")
result = or_client.complete("Explain recursion", model="openai/gpt-4o-mini", max_tokens=200)
print(f"{result.content}\n---\n{result.model} | {result.latency_ms}ms | {result.prompt_tokens}+{result.completion_tokens} tokens")
from functools import wraps
from typing import Callable
def with_cost_tracking(fn: Callable) -> Callable:
"""Middleware that logs cost per request."""
total_cost = {"value": 0.0}
@wraps(fn)
def wrapper(*args, **kwargs):
result = fn(*args, **kwargs)
# Query generation cost asynchronously
import requests
gen = requests.get(
f"https://openrouter.ai/api/v1/generation?id={result.id}",
headers={"Authorization": f"Bearer {args[0].api_key}"},
).json()
cost = float(gen.get("data", {}).get("total_cost", 0))
total_cost["value"] += cost
log.info(f"Request cost: ${cost:.6f} | Session total: ${total_cost['value']:.4f}")
return result
wrapper.total_cost = total_cost
return wrapper
Output
A typed CompletionResult per call: content, the model that actually served the request, prompt_tokens/completion_tokens, the gen-...generation_id, and latency_ms
A structured log line per request, e.g. [openai/gpt-4o-mini] 12+87 tokens, 843.2ms
Cost-tracking middleware output: per-request cost plus a running session total, e.g. Request cost: $0.000123 | Session total: $0.0045
A credits dict from check_credits() with usage and limit data from /api/v1/auth/key
Examples
Instantiate the wrapper once and make a typed call: