Codex, Behind the Harness
Conference Context
- Date/time: 2026-07-01 · 1:30pm-1:50pm
- Track/room: Agentic Engineering · Track 8
- Speaker(s): Dominik Kundel
- Session type/status: session · confirmed
- Track: Agentic Engineering
- Room: Track 8
- Session type: session
- Status: confirmed
Session Description
Agents have evolved a lot in the last year both in capabilities and in the overall structure. Increasingly sandbox-powered coding agents are breaking out to do general purpose work. In this talk we’ll be taking apart the open-source Codex agent harness. Understand how it works, what makes it so suitable to do work beyond coding tasks, how it handles key aspects like context management, tools and file system access. We’ll also tie these back to concrete actions you can take to bring these patterns into your own agents, whether you are building on top of the Codex agent or building your own.
Media Evidence
Building voice agents with OpenAI — Dominik Kundel, OpenAI (speaker-match related prior/adjacent AI Engineer video; captions: English auto-captions).
- Source video:
youtube-iXhba366fQc - Slide deck: Dense Slides: Building voice agents with OpenAI — Dominik Kundel, OpenAI — 4 visible slide image(s); 4 HTML recreation(s).
- Additional slide evidence: Slides: Building voice agents with OpenAI — Dominik Kundel, OpenAI, Reconstructed Slides: Building voice agents with OpenAI — Dominik Kundel, OpenAI
- Slide-derived themes for
youtube-iXhba366fQc: than, complex, personalized, github, voice, provide, wide, range.

Evidence Graph
This evidence graph is generated from currently linked source material: official schedule text, related video pages, cached transcripts, visible slide text, dense/reconstructed slide pages, and AI slide-classification audits.
Media Signals
youtube-iXhba366fQc— 9 slide-derived text signals- Slide-derived themes for
youtube-iXhba366fQc: than, complex, personalized, github, voice, provide, wide, range. - Evidence links for
youtube-iXhba366fQc: youtube iXhba366fQc, youtube iXhba366fQc slides, youtube iXhba366fQc dense slides, youtube iXhba366fQc reconstructed slides
Agent Reading Notes
Use these signals to refine the synopsis, topic links, people/company context, and method notes. If a source is a related external video rather than an exact official recording, keep it framed as supporting evidence.
Transcript Status
Related video transcript availability: English auto-captions. Treat this as supporting context, not a recording of this exact scheduled session unless later confirmed. Not fetched yet.
People
Supporting Slides
- youtube iXhba366fQc slides — extracted from the related public AI Engineer video.
Slide Evidence
- Slide-only cropped deck: youtube iXhba366fQc dense slides (4 viable slide images).
- Related slide/OCR pages:
- youtube iXhba366fQc dense slides
- youtube iXhba366fQc reconstructed slides
- youtube iXhba366fQc slides
- Slide-derived terms:
complex,fair,voice,parts,traces,world,than,personalized,conversations,dealing,support,okct,aine,ronteto,mdaily,augmentcode,workos,started
Synthesis
Synthesized Breakdown
Codex, Behind the Harness ## Conference Context - Date/time: 2026-07-01 · 1:30pm-1:50pm - Track/room: Agentic Engineering · Track 8 - Speaker(s): Dominik Kundel - Session type/status: session · confirmed - Track: Agentic Engineering - Room: Track 8 - Session type: session - Status: confirmed ## Session Description Agents have evolved a lot in the last year both in capabilities and in the overall structure. Increasingly sandbox-powered coding agents are breaking out to do general purpose work. In this talk we’ll be taking apart the open-source Codex agent harness. Understand how it works, what makes it so suitable to do work beyond coding tasks, how it handles key aspects like context management, tools and file system access.
Speaker And Company Context
- Dominik Kundel — Developer Experience Lead at OpenAI.
Topics Covered
Derived Links And Source Material
- youtube iXhba366fQc — related YouTube source page.
- youtube iXhba366fQc slides — slide evidence.
- youtube iXhba366fQc reconstructed slides — slide evidence.
- youtube iXhba366fQc dense slides — slide evidence.
Novel Concepts / Clever Methods
- No highlighted novel concept has been detected yet.
Evidence Boundary
This synthesis is based on the official schedule and linked source pages. It should be revisited when exact session recordings or transcript-backed secondary sources are available.