agent-state: set hterm terminal background to reflect AI agent status (ChromeOS Overview)

agent-state

#!/usr/bin/env bash
# agent-state: set the hterm terminal background based on an AI agent's status,
# so ChromeOS Overview shows at a glance which terminals are working vs done.
#
# Usage:
#   agent-state <working|done|waiting|error|reset> [agent-name]
#
# States:
#   working  -> yellow background (traffic light: agent is working)
#   done     -> green background (agent finished)
#   error    -> red background (agent hit an error)
#   waiting  -> yellow background (awaiting input)
#   reset    -> reset to default background and forget state
#
# It finds the real tty by walking up the process tree (hooks usually run with
# stdin/stdout not connected to the terminal) and writes OSC escape sequences:
#   OSC 11 (set background color), OSC 111 (reset background color)

set -u

STATE="${1:-}"
STATE_DIR="${AGENT_STATE_DIR:-$HOME/.local/state/agent-state}"

WORKING_COLOR="${AGENT_STATE_WORKING_COLOR:-#ffd700}"
DONE_COLOR="${AGENT_STATE_DONE_COLOR:-#22c55e}"
WAITING_COLOR="${AGENT_STATE_WAITING_COLOR:-#d4a017}"
ERROR_COLOR="${AGENT_STATE_ERROR_COLOR:-#dc2626}"

find_tty() {
  local pid=$$ t
  for fd in 0 1 2; do
    t=$(readlink "/proc/$pid/fd/$fd" 2>/dev/null)
    case "$t" in
      /dev/tty|/dev/pts/[0-9]*|/dev/tty[0-9]*) printf '%s' "$t"; return 0 ;;
    esac
  done
  while [ "$pid" -gt 1 ]; do
    for fd in 0 1 2; do
      t=$(readlink "/proc/$pid/fd/$fd" 2>/dev/null)
      case "$t" in
        /dev/tty|/dev/pts/[0-9]*|/dev/tty[0-9]*) printf '%s' "$t"; return 0 ;;
      esac
    done
    stat=$(cat "/proc/$pid/stat" 2>/dev/null) || return 1
    stat=${stat##*) }
    pid=$(awk '{print $2}' <<< "$stat")
    [ -z "$pid" ] || [ "$pid" = "0" ] && return 1
  done
  return 1
}

usage() {
  echo "usage: agent-state <working|done|waiting|error|reset> [agent-name]" >&2
  exit 2
}

case "$STATE" in
  working|done|waiting|error|reset) ;;
  "") usage ;;
  *) usage ;;
esac

# Allow explicit tty override for testing
TTY="${AGENT_STATE_TTY:-}"
if [ -z "$TTY" ]; then
  TTY=$(find_tty) || exit 0
fi
[ -e "$TTY" ] || exit 0

key=$(printf '%s' "$TTY" | tr '/' '_')
last_state=""
if [ -f "$STATE_DIR/$key" ]; then
  last_state=$(cat "$STATE_DIR/$key" 2>/dev/null)
fi

# only mark done if we previously saw the agent busy/working, unless forced
# (avoid painting freshly opened terminals before any work happened)
if [ "$STATE" = "done" ] && [ -z "$last_state" ] && [ -z "${AGENT_STATE_FORCE:-}" ]; then
  exit 0
fi

case "$STATE" in
  working) seq='\033]11;'"$WORKING_COLOR"'\007' ;;
  done)    seq='\033]11;'"$DONE_COLOR"'\007' ;;
  waiting) seq='\033]11;'"$WAITING_COLOR"'\007' ;;
  error)   seq='\033]11;'"$ERROR_COLOR"'\007' ;;
  reset)   seq='\033]111;\007' ;;
esac

printf '%b' "$seq" > "$TTY" 2>/dev/null || exit 0

mkdir -p "$STATE_DIR" 2>/dev/null
if [ "$STATE" = "reset" ]; then
  rm -f "$STATE_DIR/$key"
else
  printf '%s' "$STATE" > "$STATE_DIR/$key"
fi
exit 0

agent-status.js

import { appendFileSync } from "node:fs"

const LOG = "/tmp/opencode-agent-events.log"

export const AgentStatus = async ({ $ }) => {
  let q = Promise.resolve()
  const run = (state) => {
    q = q.then(async () => {
      try {
        await $`/home/zonca/.local/bin/agent-state ${state} opencode`
      } catch {}
    })
    return q
  }
  return {
    event: async ({ event }) => {
      const sid = event.properties?.sessionID ?? "?"
      const st = event.properties?.status?.type ?? ""
      try {
        appendFileSync(LOG, `${new Date().toISOString()} ${event.type} ${st} ${sid}\n`)
      } catch {}
      if (event.type === "session.status") {
        if (st === "busy" || st === "retry") {
          await run("working")
        } else if (st === "idle") {
          await run("done")
        }
      } else if (event.type === "session.idle") {
        await run("done")
      } else if (event.type === "session.error") {
        await run("error")
      }
    },
  }
}