cecil-sdk 0.2.1

Lightweight LLM observability SDK with privacy-first defaults

Cecil Python SDK

cecil-sdk is a privacy-first Python SDK for LLM cost visibility and cache optimization insights.

Install

pip install cecil-sdk

Quickstart

import cecil

cecil.patch()

Default behavior is local-only. No telemetry is sent unless explicitly enabled. Current instrumentation targets synchronous provider clients.

Usage Analytics Report

import cecil
from openai import OpenAI

session = cecil.start_session()
client = OpenAI()
client.chat.completions.create(
    model="gpt-4o-mini",
    messages=[{"role": "user", "content": "Summarize this SDK in one sentence."}],
)

session.print_report(usd_decimals=8)
session.save_json("cecil_usage_report.json", usd_decimals=8)
session.close()

Why Cecil

• Privacy-first defaults (hashed metadata, no raw prompt export by default)
• Fail-open instrumentation (SDK failures do not break provider calls)
• Actionable cost and cache opportunity analytics
• Lightweight integration (import cecil; cecil.patch())

Current Scope

• OpenAI sync path: openai.resources.chat.completions.Completions.create
• Anthropic sync path: anthropic.resources.messages.Messages.create
• Async provider clients are not instrumented in the current release.

Development

pip install -e ".[dev]"
make lint
make typecheck
make test
make build
python -m twine check dist/*
python scripts/smoke_check_wheel.py

Documentation

• docs/quickstart.md
• docs/telemetry-opt-in.md
• docs/privacy-contract.md
• docs/recommendations.md
• docs/release-checklist.md

License

MIT. See LICENSE.