Selection

A selection override sets what runs a step: which model, how much effort, what depth, which skills, and any connector-specific invocation options. Every field is optional. An override that sets nothing contributes nothing.

Layers

Overrides apply at seven layers. Later layers win.

Layer	Where it lives
`default`	Circuit's built-in baseline.
`user-global`	`~/.config/circuit/config.yaml`.
`project`	`.circuit/config.yaml`.
`flow`	Declared by the flow package.
`stage`	Declared by the flow package, for one stage.
`step`	Declared by the flow package, for one step.
`invocation`	Passed on a single run.

The three middle layers are flow-authored: a flow can pin what a stage or step needs, and that declaration outranks your project config. Only invocation outranks the flow.

In a config file, a selection override lives at defaults.selection (applies to every run) or under circuits.<flow>.selection (applies to one flow).

Example

schema_version: 1
defaults:
  selection:
    model:
      provider: anthropic
      model: claude-opus-4-8
    effort: high
    depth: medium
circuits:
  fix:
    selection:
      effort: max
      skills:
        mode: append
        skills: [tdd]
      invocation_options:
        temperature: 0

Config files parse with .strict(): an unknown key is rejected, so a typo fails at parse time instead of silently dropping your override.

Fields

Field	Description
`model`	A `provider` (`openai`, `anthropic`, `gemini`, or `custom`) and a `model` string.
`effort`	One of `none`, `minimal`, `low`, `medium`, `high`, `xhigh`, `max`.
`depth`	One of `low`, `medium`, `high`, `tournament`, `autonomous`.
`skills`	A skill operation (see below).
`invocation_options`	A JSON object passed to the connector. Merged right-biased by layer.

Skills

skills is a typed operation, not a plain list. Set mode, and for any mode but inherit, a skills list. Lists must not contain duplicates.

Mode	Effect
`inherit`	Keep the prior layer's skills. The default.
`replace`	Use this list. `[]` clears the set.
`append`	Add these to the prior set.
`remove`	Drop these from the prior set.

Selection and the power dial

The power dial fills model and effort only when no layer set them: it is what decides which model fills each step's archetype. An explicit model or effort in any selection override wins over the dial. Set the dial itself with --power on a run or defaults.power in config; both accept auto, low, medium, or high. With auto, the run's researcher recommends a tier, the engine clamps it to the power_auto bounds, and the receipt reports the resolution, such as power low (auto). Per-connector tier tables live under power_tiers (see Connectors).

Layers

Example

Fields

Skills

Selection and the power dial

Related

On this page