LESSON 7.2 · Engineering · 110 min

Tool calling and structured output

Tool calling and structured output. Learn schemas, validation, idempotency, and side effects and complete: Implement a safe tool layer with retries. Part of the “From Models to Int

Learning objectives

  1. Explain what problem “Tool calling and structured output” solves without hiding behind terminology.
  2. Trace the variables and causal links across schemas, validation, idempotency.
  3. Complete “Implement a safe tool layer with retries” and judge the result with evidence rather than intuition.

Core concepts

schemas

schemas is part of the lesson’s causal model. State its inputs, outputs, invariants, and failure mode; then verify it with a hand-check or a minimal experiment before moving to an optimized implementation.

validation

validation is part of the lesson’s causal model. State its inputs, outputs, invariants, and failure mode; then verify it with a hand-check or a minimal experiment.

idempotency

idempotency is part of the lesson’s causal model. State its inputs, outputs, invariants, and failure mode; then verify it with a hand-check or a minimal experiment.

and side effects

and side effects is part of the lesson’s causal model. State its inputs, outputs, invariants, and failure mode; then verify it with a hand-check or a minimal experiment.

Build and verify

Implement a safe tool layer with retries

  • Predict: write the expected output, trend, or failure before running code.
  • Build: implement only the minimum components needed to answer the question.
  • Verify: compare with a baseline or trusted implementation; save seeds, parameters, and raw outputs.
  • Transfer: change one shape, dataset, scale, or workload condition and explain whether the conclusion still holds.

Open the complete interactive lesson