chronograf container influx link failure

I'm trying to configure chronograf to point to influxdb via docker-compose, but when I open chronograf in my browser, it still prompts for influxdb connection details. Am I doing something wrong?

version: "2"
services:
  telegraf:
    image: "telegraf-compose:1.2"
    links:
      - influxdb
    ports:
      - "8125:8125/udp"
  influxdb:
    image: "influxdb:1.2"
    ports:
      - "8086:8086"
  chronograf:
    image: "chronograf:1.2beta"
    links:
      - influxdb
    ports:
      - "8888:8888"
  kapacitor:
    image: "kapacitor:1.2"
    links:
      - influxdb
    ports:
      - "9092:9092"
    environment:
      KAPACITOR_INFLUXDB_0_URLS_0: "http://influxdb:8086"

(The telegraf-compose:1.2 and chronograf:1.2beta images are technically custom images, built similarly to the official ones in order to fill gaps in the Docker Compose experience for the TICK stack, like defaulting the influxdb address from localhost to influxdb for chronograf.)

Start with the provided docker-compose YAML and the custom chronograf:1.2beta image configuration, then inspect how the Chronograf container receives the linked InfluxDB address. Reproduce the startup in Docker Compose and determine what configuration is missing when the browser still prompts for connection details; done means Chronograf connects to the influxdb service without that prompt.