costkey 0.2.0

AI cost observability. Track every LLM call's cost, tokens, and latency with one line of code.

costkey

AI cost observability. Track every LLM call's cost, tokens, and latency with one line of code.

Install

pip install costkey

Quick Start

import costkey

costkey.init(dsn="https://[e-mail]/your-project")

# That's it. Every AI call is now tracked automatically.
# Works with OpenAI, Anthropic, Google Gemini, Azure OpenAI.

No wrapping. No per-client setup. No manual tagging. CostKey patches httpx and requests and auto-detects AI provider calls.

What You Get (Zero Config)

All of these work automatically after init():

• Cost tracking — per-call cost computed from built-in pricing (30+ models)
• Stack trace attribution — see which function, file, and line made each AI call
• Request tracing — group AI calls per request with start_trace()
• Feature detection — call chains are analyzed to detect logical "features" in your code
• Credential scrubbing — API keys, JWTs, and secrets are auto-redacted from captured bodies

How It Works

CostKey patches httpx.Client.send and requests.Session.send. When your code calls any AI provider:

1. Detects the provider from the URL (OpenAI, Anthropic, Google, Azure)
2. Extracts token usage from the response
3. Captures a stack trace for automatic code attribution
4. Computes cost using built-in model pricing
5. Ships the event async to your CostKey dashboard

Non-AI HTTP calls pass through untouched with zero overhead.

Tracing

# Group all AI calls in a request into one trace
with costkey.start_trace(name="POST /api/search"):
    intent = classify_intent(query)        # AI call 1
    results = search(query, intent)
    summary = summarize_results(results)   # AI call 2
    reranked = rerank_results(results)     # AI call 3

# Dashboard shows one trace with all 3 calls and total cost

Manual Context

with costkey.with_context(task="summarize", team="search"):
    response = openai.chat.completions.create(...)

Privacy & Security

• Never captures API keys — request headers are never read
• Auto-scrubs credentials from captured bodies (OpenAI keys, JWTs, tokens, etc.)
• before_send hook for custom PII scrubbing:

def scrub(event):
    event.request_body = None  # strip prompts entirely
    return event

costkey.init(dsn="...", before_send=scrub)

Supported Providers

Provider	Auto-detected	Patches
OpenAI	api.openai.com	httpx, requests
Anthropic	api.anthropic.com	httpx, requests
Google Gemini	generativelanguage.googleapis.com	httpx, requests
Azure OpenAI	*.openai.azure.com	httpx, requests
Google Vertex AI	*-aiplatform.googleapis.com	httpx, requests

API

costkey.init(dsn, **options) — Initialize. Call once at startup.

costkey.with_context(**kwargs) — Context manager for custom tags.

costkey.start_trace(name) — Context manager for request tracing.

costkey.shutdown() — Flush and restore original HTTP clients.

costkey.register_extractor(extractor) — Add custom AI provider.

costkey.register_pricing(model, ...) — Add custom model pricing.

Also available for TypeScript

npm install costkey

import { CostKey } from 'costkey'
CostKey.init({ dsn: 'https://[e-mail]/proj' })

License

MIT