Design APIs an agent can actually call: contracts, idempotency, and error surfaces.

In Lesson 3.2 of GROW Course 3 (Production Agentic Systems), Doug Liles works through it with you. API design rules that make your service safe for an autonomous caller.

What you'll take away

- Designing for an agent caller

- Contracts

- Idempotency

Chapters

(0:00) Cold open & the promise

(5:16) Designing for an agent caller

(10:32) Contracts

(15:49) Idempotency

(21:05) Error surfaces

(26:22) Versioning

(31:38) The artifact & what to do Monday

Study guide, slide deck, blog companion, infographic (free)

- https://fde.goodcombinator.ai/lessons/FDE_Lesson_3_2

Audio companion is AI-narrated using NotebookLM. Explainer video is human-produced.

Public release

This full FDE Certification audio lesson is available publicly as part of GROW by Good Combinator.

Continue in GROW Skills Library: https://goodcombinator.com/grow/library

Episode metadata

Show: GROW by Good Combinator

Course: Course 3 - Production Agentic Systems

Lesson: 3.2

Season/Episode: 3/2

Runtime: 36:55

Access label: public-full-lesson

Source channel: spotify

Source audio: app/lessons/assets/course-3/3.2/3.2 audio podcast.m4a

Taxonomy: Domain=Production Agentic Systems; Career stage=FDE; Skill level=Intermediate; Asset type=Capstone; Outcome=Build

CRM events: course_started, lesson_completed, cert_enrolled

Transcript and accessibility

Final transcript required before launch: https://goodcombinator.com/grow/courses/course-3/lesson-3.2/transcript

Accessibility requirement: reviewed audio, clear title, descriptive show notes, and transcript availability before launch.

Audio companion is AI-narrated using NotebookLM and disclosed here.

Credits

Host: Doug Liles

Producer: Good Combinator

Audio: NotebookLM AI narration (disclosed)