chatlas 0.8.0

New features

• New .on_tool_request() and .on_tool_result() methods register callbacks that fire when a tool is requested or produces a result. These callbacks can be used to implement custom logging or other actions when tools are called, without modifying the tool function (#101).
• New ToolRejectError exception can be thrown from tool request/result callbacks or from within a tool function itself to prevent the tool from executing. Moreover, this exception will provide some context for the the LLM to know that the tool didn't produce a result because it was rejected. (#101)

Improvements

• The CHATLAS_LOG environment variable now enables logs for the relevant model provider. It now also supports a level of debug in addition to info. (#97)
• ChatSnowflake() now supports tool calling. (#98)
• Chat instances can now be deep copied, which is useful for forking the chat session. (#96)

Changes

• ChatDatabricks()'s model now defaults to databricks-claude-3-7-sonnet instead of databricks-dbrx-instruct. (#95)
• ChatSnowflake()'s model now defaults to claude-3-7-sonnet instead of llama3.1-70b. (#98)

Bug fixes

• Fixed an issue where ChatDatabricks() with an Anthropic model wasn't handling empty-string responses gracefully. (#95)