Using multiple tools

• Tool Implementation Already Provided: The code for add_duration_to_date_time and set_reminder functions was pre-built in the tools and schemas cell

• Two Schemas Required: Both add_duration_to_date_time_schema and set_reminder_schema must be passed to Claude so it knows these tools exist

• Update run_conversation Function: Add both tool schemas to the list of tools that Claude can access

• Update run_tool Function: Add conditional logic (if/case statements) to check the tool name and call the appropriate function with the tool input arguments

• Tool Function Pattern: Use **tool_input to unpack arguments when calling the actual tool functions

• Scaling is Simple: Once the core framework is built, adding new tools requires only three steps:
• Update the run_tool function with a new case
• Add the tool schema to Claude's available tools
• Implement the actual tool function

• Multi-Step Tool Calls: Claude can chain multiple tool calls together (e. g. , first calculate a date, then use that result to set a reminder)

• Tool Results Flow: User message → Assistant uses tool → Tool results returned → Assistant provides final response, all tracked in conversation history

• Message Structure: Messages can contain multiple blocks (text blocks and tool use blocks) in a single response

Takeaways

• Tool schemas must be passed to Claude so it knows what tools are available
• The run_tool function needs conditional logic to route tool calls to the correct function
• Use **tool_input to unpack arguments when calling tool functions
• Claude can chain multiple tool calls together in sequence
• Adding new tools requires only three steps: update run_tool, add schema to Claude's tools, and implement the function