References

Use task_name.output_name to pass a value or reuse an allocation from an earlier task. The source task must precede the consuming task in the dependency graph.

Syntax

devices:
  station: prepare.station
resources:
  beaker: prepare.beaker
parameters:
  volume: prepare.measured_volume
files:
  raw_data: analyze.chromatogram.csv

Keys on the left are the consuming task’s aliases or parameter names. References on the right identify the upstream task and its output. File names may contain dots.

Example

- name: analyze_color
  type: Analyze Color
  dependencies: [mix_colors]
  devices:
    color_station: mix_colors.color_station
  resources:
    beaker: mix_colors.beaker

- name: score_color
  type: Score Color
  dependencies: [analyze_color]
  parameters:
    red: analyze_color.red
    green: analyze_color.green
    blue: analyze_color.blue
    total_color_volume: mix_colors.total_color_volume
    max_total_color_volume: 300.0
    target_color: eos_dynamic

The first task reuses the station and beaker selected for mixing. The second consumes the measured RGB values. See Color Mixing for the complete protocol.

A reference identifies an allocation but does not reserve it between tasks. Use Scheduling holds when another protocol run must not claim the device or resource in between. See Protocols for fan-in references after conditional branches.