a chat command that sends your visible terminal state to GPT and preloads the reply as your next command.

chat.sh

#!/usr/bin/env zsh
# chat – ask OpenAI using the last visible terminal lines (curl + jq)

chat() {
  local lines=30              # how many terminal lines to capture
  local model="gpt-4.1-nano"  # default model
  local verbose=false
  local -a query_parts=()

  # -------------------- parse options --------------------
  while (( $# )); do
    case "$1" in
      -l|--lines)
        [[ -n $2 && $2 != -* ]] || { echo "Option $1 needs a value" >&2; return 1; }
        lines=$2; shift 2 ;;
      -m|--model)
        [[ -n $2 && $2 != -* ]] || { echo "Option $1 needs a value" >&2; return 1; }
        model=$2; shift 2 ;;
      -v|--verbose)
        verbose=true; shift ;;
      -h|--help)
        cat <<'HELP'
chat — ask OpenAI for the next shell command
  -l, --lines N   number of terminal lines to send (default 30)
  -m, --model M   model name (default gpt-4.1-nano)
  -v, --verbose   print curl request, raw JSON response, and parsed command
  -h, --help      show this help
  --              stop option parsing; everything after is query text
Examples:
  chat git commit -m "initial"
  chat --model gpt-4o-mini -v how to write a Makefile
  chat how to use ls -l -- -R
HELP
        return 0 ;;
      --)                     # explicit end of options
        shift; query_parts+=("$@"); break ;;
      -*)
        echo "Unknown option: $1" >&2; return 1 ;;
      *)
        query_parts+=("$1"); shift ;;
    esac
  done
  (( ${#query_parts} )) || { echo "No query given" >&2; return 1; }
  local query="${(j: :)query_parts}"
  # -------------------------------------------------------

  [[ -z $OPENAI_API_KEY ]] && { echo "OPENAI_API_KEY not set" >&2; return 1; }

  # --------------- capture terminal excerpt --------------
  if [[ -z $TMUX ]]; then
    echo "Not inside tmux; can't capture pane output." >&2
    return 1
  fi
  local pane
  pane=$(tmux capture-pane -p -S -$((lines+1)) | sed '$d' | tail -n $lines)

  # ------------------ build prompt -----------------------
  local prompt="You are a CLI assistant. Given the following terminal \
session excerpt, reply with ONLY the next shell command—no explanations, \
no markdown.

Terminal excerpt:
$pane

Request: $query"

  local payload
  payload=$(jq -n --arg model "$model" --arg p "$prompt" \
              '{model:$model, input:$p, temperature:0.3, background:false}')

  # ------------------ headers ----------------------------
  local -a headers=(
    -H "Content-Type: application/json"
    -H "Authorization: Bearer $OPENAI_API_KEY"
  )
  [[ -n $OPENAI_PROJECT_ID ]] && headers+=(-H "OpenAI-Project: $OPENAI_PROJECT_ID")
  [[ -n $OPENAI_ORG_ID    ]] && headers+=(-H "OpenAI-Organization: $OPENAI_ORG_ID")

  # ------------------ request ----------------------------
  local -a curl_cmd=(curl -s https://api.openai.com/v1/responses "${headers[@]}" -d "$payload")
  local response
  response=$("${curl_cmd[@]}")

  # handle API-side errors early
  if jq -e '.error' >/dev/null 2>&1 <<<"$response"; then
    jq -r '.error.message' <<<"$response" >&2
    return 2
  fi

  # ------------------ extract command --------------------
  local cmd
  cmd=$(jq -r '
        if .output then
          .output[].content[].text?
        elif .choices then
          .choices[].message.content?
        else empty end' <<<"$response" |
        sed -e 's/^```[[:alpha:]]*//' -e 's/```$//' \
            -e 's/^[[:space:]]*//'  -e 's/[[:space:]]*$//')

  [[ -z $cmd ]] && { echo "No command received." >&2; return 2; }

  # ------------------ verbose block ----------------------
  if [[ $verbose == true ]]; then
    echo "CURL REQUEST:"
    echo "curl -s https://api.openai.com/v1/responses \\"
    for h in "${headers[@]}"; do
      echo "  $h \\"
    done
    echo "  -d '$payload'"
    echo
    echo "RAW RESPONSE:"
    echo "$response"
    echo
    echo "PARSED COMMAND:"
    echo "$cmd"
    echo
  fi

  # ------------- preload into command line ---------------
  if [[ -o interactive && $+functions[zle] -eq 1 ]]; then
    BUFFER="$cmd"
    CURSOR=${#BUFFER}
    zle -R                     # redraw prompt
  else
    # fall back: queue it into history & next prompt
    print -z -- "$cmd"
  fi
}