Haystack by deepset vs. Microsoft Bing Spell Check API

Haystack is deepset's open-source Python AI orchestration framework for building customizable, production-grade AI agents and workflows. Connect components like language models, vector databases, and file converters into pipelines and agents that retrieve, reason, and act on your own data; use hooks to control the agent loop: enforce a token budget before the next LLM call, incorporate human approval before a risky tool call, or use compaction to keep context small.

Microsoft Bing Spell Check API is a tool that help users correct spelling errors, recognize the difference among names, brand names, and slang, as well as understand homophones as they're typing.