• Codex Built-in (Priority): When

  $imagegen

  /

  image_gen

  is available in the current Codex CLI session, generate and save directly; counted towards Codex general usage, no

  OPENAI_API_KEY

  or

  GPT_IMAGE_API_KEY

  required, and no

  curl

  execution.

  story-cover

  calls the tool automatically, no need for users to run additional commands.
• API Fallback: Only used when the session has no built-in tool or the user explicitly specifies the API, requires

  GPT_IMAGE_API_KEY

  . Missing tools does not mean Codex subscription does not support image generation; report errors first when built-in calls fail, do not silently switch to potentially paid APIs.

BOOK_DIR

./covers/<Book Title>

REF_IMAGE

Book title and pen name are mandatory for the cover: If either is missing, you must ask the user to complete it using AskUserQuestion, do not fabricate or leave blank.

GPT_IMAGE_SIZE

768x1024

1024x1536

export GPT_IMAGE_SIZE

UPLOAD_SIZE

600x800

• Single genre match → Directly adopt
• Multiple genre matches → Select by priority: Xianxia > Western Fantasy > Ancient Romance > Modern Romance > Urban > Suspense > Sci-Fi > History > Supernatural > Light Novel
• No matches → Default to

  Urban

small refined white serif text with faint golden glow, flanked by delicate cloud-scroll ornaments on both sides, resting on a thin horizontal gold line

small clean white modern text with subtle drop shadow, positioned above a thin silver horizontal divider line

small elegant dark red traditional text inside a thin golden rectangular border frame with corner decorations

small soft pink-white handwritten text with a tiny heart motif on the left side, light sparkle effect

small pale grey text with slight blur effect, almost hidden in the shadows, a thin cracked line underneath

small crisp white monospace text with subtle cyan scanline overlay, flanked by small geometric brackets

small bronze medieval script text with aged parchment texture, enclosed in a small decorative shield or banner shape

small dignified white Song typeface text above a double horizontal line in dark red

small faded grey-green text slightly tilted, with a thin dripping ink line above

small playful rounded white text with pastel color outline, tiny star decorations on both sides

• Size:

  small

  (not too large to steal the title's focus, nor too small to be unreadable)
• Position:

  at bottom center

  , with appropriate spacing from the bottom of the frame
• Must have decorative elements: At least one of lines/borders/small icons/light effects
• Color contrasts with the background but is not glaring

• The more specific the character description, the better: Specify each dimension of clothing, posture, hairstyle, expression, props
• Layered background: Foreground (characters) → Middle Ground (scene) → Background (atmosphere)
• Light effects specify light source direction + color (e.g.,

  dramatic golden light from above

  )
• Use

  digital painting style

  instead of

  photo

  to avoid real photo feel

1. Call

   image_gen

   with the complete prompt from Step 3. Write the ratio and safe area into the prompt, do not pass API parameters like

   GPT_IMAGE_MODEL

   ,

   GPT_IMAGE_SIZE

   ,

   response_format

   .
2. When

   REF_IMAGE

   is provided, load local files into the session using an image viewer first; download URLs first then load. Explain whether it is an editing target or style reference, and list the content that must be retained.
3. Call the tool separately for each composition scheme. Create

   BOOK_DIR/封面/

   first, then copy the tool-returned image as

   封面_vN.png

   , where

   N

   increments and does not overwrite old versions; retain the original file in

   $CODEX_HOME/generated_images/

   , and save a corresponding

   .prompt.txt

   file, plus

   .ref.txt

   if there is a reference image. Confirm the image is readable, and pass the absolute path of the original image to Step 5.

_上传

SRC

TARGET

SRC='<Absolute path of original image generated in Step 4>'
TARGET='<Platform upload size determined in Step 1; leave blank if none>'
[ -f "$SRC" ] || { echo "封面原图不存在: $SRC" >&2; exit 1; }
if [ -n "$TARGET" ] && [ -f "$SRC" ]; then
  UP="${SRC%.png}_上传.png"; W="${TARGET%x*}"; H="${TARGET#*x}"
  if command -v magick >/dev/null 2>&1; then M=magick
  elif command -v convert >/dev/null 2>&1; then M=convert; else M=""; fi
  if [ -n "$M" ]; then
    "$M" "$SRC" -resize "${W}x${H}^" -gravity center -extent "${W}x${H}" "$UP"  # Scale to fill then center crop
  elif command -v sips >/dev/null 2>&1; then
    cp "$SRC" "$UP"
    sw=$(sips -g pixelWidth "$UP" | awk '/pixelWidth/{print $NF}')
    sh=$(sips -g pixelHeight "$UP" | awk '/pixelHeight/{print $NF}')
    if [ $((sw*H)) -ge $((sh*W)) ]; then sips --resampleHeight "$H" "$UP" >/dev/null
    else sips --resampleWidth "$W" "$UP" >/dev/null; fi
    sips -c "$H" "$W" "$UP" >/dev/null   # sips -c is height first, width second, center crop
  else
    echo "无 magick/convert/sips，跳过；手动把 $SRC 居中裁剪+缩放到 $TARGET 再上传" >&2
  fi
  [ -f "$UP" ] && file "$UP"
fi

The book title/pen name have been placed in the central safe area in the prompt, so center cropping will not cut them.

• Reply in the user's language; use the same language as the user's input
• Follow Chinese Copywriting Guidelines for Chinese replies