Core

Policy and presets

Settings for streaming text, tool updates, response status, announcement channels, timing, and queue limits.

PresetName

Each preset defines a complete set of default values.

Preset	Streaming	Status updates
minimal	Restrained	Final states
balanced	Sentence-paced	Useful status
verbose	More frequent	Progress enabled
completion-only	Final text only	Minimal

PolicyOverrides

Nested overrides merge with the selected preset. Unspecified values remain controlled by that preset.

typescript

const runtime = createGenerativeA11y({
  preset: "balanced",
  policy: {
    text: { minimumCharacters: 48, maximumDelayMs: 1_800 },
    tools: { announceProgress: false },
    minimumGapMs: 900,
    maxQueueSize: 64,
  },
});

How this code works

01
Keep a tested baseline
balanced continues to supply every property not shown.
02
Tune useful differences
Text becomes less fragmented and tool progress remains quiet.
03
Keep work bounded
maxQueueSize prevents an inactive consumer from creating unlimited pending output.

Options and return values

text.strategyTextStrategyOptional

Selects silent, sentence, paragraph, or completion segmentation.

Default: preset value

text.minimumCharactersnumberOptional

Avoids tiny fragments except when a terminal or maximum-delay flush applies.

Default: preset value

text.maximumDelayMsnumberOptional

Bounds how long useful buffered text waits for a natural boundary.

Default: preset value

minimumGapMsnumberOptional

Paces adjacent intents to reduce interruption and overlap.

Default: preset value

dedupeWindowMsnumberOptional

Suppresses equivalent recent output.

Default: preset value

maxQueueSizenumberOptional

Bounds scheduler candidates and favors content over status during eviction.

Default: preset value

maxActiveEntitiesnumberOptional

Bounds response and tool identity state and fails closed after capacity.

Default: preset value