claudebox/.planning/phases/03-sandbox-aware-prompting/03-01-SUMMARY.md

phase	plan	subsystem	tags	dependency_graph	tech_stack	key_files	decisions	metrics
03-sandbox-aware-prompting	01	sandbox-prompting	shell claude-code sandbox-context	requires provides affects SANDBOX.md-generation CLAUDE.md-import claudebox.sh	added patterns heredoc-generation atomic-file-prepend	created modified claudebox.sh	Used head-1 string comparison instead of grep for first-line check (simpler, no grep dependency needed)	duration completed tasks files 76s 2026-04-09 2 1

Phase 03 Plan 01: Sandbox-Aware Prompting Summary

SANDBOX.md heredoc generation and CLAUDE.md import management via head-1 check with atomic mktemp+mv prepend

What Was Done

Task 1: Add SANDBOX.md generation and CLAUDE.md import check

Inserted a new block in claudebox.sh between mkdir -p ~/.claudebox and gitconfig generation. The block:

1. Writes ~/.claudebox/SANDBOX.md via single-quoted heredoc (no variable expansion) on every launch. Content covers: sandbox overview, tool installation (comma + nix shell), default restrictions with "by default" phrasing, and git identity/HTTPS guidance.

2. Manages ~/.claudebox/CLAUDE.md import line: creates file with @SANDBOX.md if missing, or prepends the import if first line doesn't match. Uses mktemp+mv for atomic write, preserving existing user content.

Task 2: End-to-end verification

Verified three scenarios via claudebox --dry-run --yes:

• First run (no files): SANDBOX.md created with correct content, CLAUDE.md created with @SANDBOX.md
• Idempotency: Second run produces no duplicate import lines
• Prepend: User content without import gets @SANDBOX.md prepended, existing content preserved

Commits

Task	Commit	Description
1	27d9db4	feat(03-01): add SANDBOX.md generation and CLAUDE.md import check
2	(verification only, no code changes)

Deviations from Plan

None - plan executed exactly as written.

Self-Check: PASSED