# Chapter 11 - The Full Sensorimotor Loop | Loop Engineering

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# Chapter 11 - The Full Sensorimotor Loop

                Last updated 2026-07-13. This page hosts the extended worked example for Chapter 11 - one complete task walkthrough from user intent to verified result - plus the source documents the chapter's sequence diagram condenses.

### Companion activity

Trace one task end to end through the full loop, naming the handoff at each transition and the check that would catch a failure there.

### What this chapter argues

                Parts I and II treated the regions one at a time. Chapter 11 puts them together: a single task, traced through dialog interface to working memory to prefrontal cortex to motor / sensory to long-term memory and back. The chapter argues that the discipline that matters most is at the handoffs - the transitions between layers - not within any single layer. A well-disciplined transition makes a mediocre layer adequate. A sloppy transition makes an excellent layer useless.

### Key sources

Chapter 11 cites in the print book: D23. Entries below are the sources this page draws on; some are related literature cited elsewhere in the book rather than in this chapter.

- D10 - Anthropic. (2024). Building effective agents . [anthropic.com/engineering/building-effective-agents](https://www.anthropic.com/engineering/building-effective-agents)

- D11 - Willison, S. (2025). Designing agentic loops . [simonwillison.net/2025/Sep/30/designing-agentic-loops](https://simonwillison.net/2025/Sep/30/designing-agentic-loops/)

### Primary-source links

- [Anthropic, "Building effective agents"](https://www.anthropic.com/engineering/building-effective-agents) - for the multi-step agent pattern that informs the sequence diagram.

- [Willison, "Designing agentic loops"](https://simonwillison.net/2025/Sep/30/designing-agentic-loops/) - for the handoff-discipline framing the chapter draws on.

- The chapter's sequence diagram is Figure 11.1 in the print book; this page's worked example traces the same handoffs step by step.

### Chapter contents

- The eight-step sequence diagram for one complete task.

- The handoff discipline at each transition: what each layer owes the next.

- A single worked example that runs the full loop end to end.

- What the failure looks like at each handoff (forward reference to Chapter 12).

### Related resources

                Use the [worked examples](/examples/) to inspect end-to-end traces, including full dialog transcripts, multi-step agent action logs, and the per-layer state captured at each handoff.