apex-accelerator: Instructions file for GitHub Copilot

MANDATORY: File Operation Override

[!CAUTION] Terminal heredoc/redirect operations (cat <<EOF, echo "..." >, printf >, tee <<EOF) corrupt files in VS Code Copilot due to tab-completion interference, escape failures, and exit-code 130 interruptions. This is a hard technical requirement.

Rule

NEVER use cat, echo, printf, tee, or >>/> to write multi-line content to a file. Use file creation/editing tools instead.

Allowed Terminal Commands

Package management, builds, tests, git, running scripts, filesystem navigation (ls, cd, mkdir, rm), and downloads (curl, wget — not piped to files with content manipulation).

Sub-rule: No heredoc'd code into node -e / python3 -c

Piping a heredoc into node -e or python3 -c is forbidden when the code contains shell-meaningful constructs. The shell expands them before the interpreter sees them and you typically get a SyntaxError: Invalid or unexpected token (or silently wrong output).

Forbidden constructs in heredoc bodies:

• Backtick template literals (`${value}`) — interpreted as command substitution.
• ${variable} — interpreted as parameter expansion.
• $(command) — interpreted as command substitution.
• \u0000 and other escape sequences the shell touches before passing on.

Forbidden patterns (and what to do instead):

• node -e "<<EOF ... EOF" containing any of the constructs above → write the script to tmp/run-once.mjs with the file-edit tool, then run node tmp/run-once.mjs.
• python3 -c "$(cat <<EOF ... EOF)" containing any of the constructs above → write the script to tmp/run-once.py then run python3 tmp/run-once.py.
• cat <<EOF | node — same fix, use a temp file.

The temp file lets the agent's file-editing tools control quoting and escape sequences end-to-end, instead of negotiating shell, heredoc, and interpreter layers all at once.

Sub-rule: No writes to agent-output/** via shell

Subagents and step agents MUST NOT use heredocs, >/>>, or tee to write any file under agent-output/**. Artifact writes must go through the file-editing tools (create_file, replace_string_in_file, multi_replace_string_in_file). Read-only inspection (ls, cat, wc -l) of existing agent-output/** files is fine.