OnceOnly Python SDK v2.0.0 — AI-Agent Ready Idempotency

Changelog

All notable changes to this project will be documented in this file.

The format is based on Keep a Changelog
and this project adheres to Semantic Versioning.

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[v2.0.0] — 2026-01-XX

Added

• AI-first SDK architecture
• Stable idempotency hashing for:
  • Pydantic v1 / v2 models
  • Dataclasses
  • Bytes / complex structured inputs
• Optional LangChain integration:
  • make_idempotent_tool
  • Support for StructuredTool (multi-argument tools)
• AI helpers for long-running backend jobs:
  • ai.run_and_wait
  • ai.run_and_wait_async
• Automatic Retry-After parsing for 429 responses
• Configurable retry logic for rate limits
• Metadata support for tracing (agent id, trace_id, custom context)
• Clear example separation:
  • examples/general/
  • examples/ai/

Changed

• Complete internal refactor of client architecture
• Unified error handling and response parsing
• Improved fail-open logic for production safety
• More explicit and descriptive docstrings (AI / agent friendly)
• Examples rewritten to reflect real-world AI-agent usage

Fixed

• Unstable hashing caused by repr() memory addresses
• LangChain tool execution issues with multiple arguments
• Retry-After header handling inconsistencies
• Edge cases in duplicate detection under retries

Removed

• Legacy v1 SDK stru