---
id: TASK-7.3
title: Document new run behavior and fallback
status: Done
assignee:
  - codex
created_date: '2026-02-03 16:23'
updated_date: '2026-02-03 16:32'
labels: []
dependencies: []
parent_task_id: TASK-7
---

## Description

<!-- SECTION:DESCRIPTION:BEGIN -->
Update user-facing docs to describe that `zync run` executes the built Zephyr binary directly when available (with extra args), and falls back to `ninja run` without extra args when not found.
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## Acceptance Criteria
<!-- AC:BEGIN -->
- [x] #1 Docs explain direct binary execution for `zync run` and how extra args are passed.
- [x] #2 Docs explain fallback to `ninja run` and that extra args are not passed in that case.
- [x] #3 Docs mention expected binary location under build dir/image (e.g., `zephyr/zephyr.exe`).
<!-- AC:END -->

## Implementation Plan

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1. Update README run/args section to mention `zync run` executes zephyr/zephyr.exe when present, passing extra args.
2. Document fallback to `ninja run` without extra args when the binary is missing.
3. Include the expected binary location under build dir/image (zephyr/zephyr.exe).
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## Implementation Notes

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Updated README.md to document `zync run` executing zephyr/zephyr.exe when present (passing extra args) and fallback to `ninja run` without extra args when missing. Tests not run for doc-only change.
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