Session 5· 10· 10 min
Format vs Tools — when to use which
What you'll learn
- ▸Distinguish response_format (data extraction) from tools (actions)
- ▸See a decision flowchart for choosing the right approach
- ▸Know when you need both
Both structured output and tool calling constrain what the model returns. They look similar but they solve different problems. Getting this distinction right is a Phase 1 → Phase 2 bridge.
response_format
for DATA
- •Use when: your code READS the output
- •Returns: a schema-shaped object
- •Nothing gets "called"
- •Examples: data extraction, classification, form filling
tools
for ACTIONS
- •Use when: your code EXECUTES the output
- •Returns: a request to run a function
- •Your code runs the function and replies
- •Examples: weather lookup, DB query, API call
Rule of thumb
If your code READS the result → structured output. If your code EXECUTES the result → tools. If both → use both; the API supports mixing response_format with tools.
$ python 10_format_vs_tooling_decision.py
Knowledge Check
You want the model to extract an address from a block of text. Which do you use?
Knowledge Check
You want the chatbot to look up a flight price from an API. Which do you use?
Recap — what you just learned
- ✓response_format = model returns data in a shape
- ✓tools = model returns a request for YOUR code to execute
- ✓Use both together when you need extracted data AND actions
- ✓Phase 2 (next 6 lessons) is all about tools