set_model: Set Default Model

In aisdk: Unified Interface for AI Model Providers

Set Default Model

Description

Sets the package-wide default language model. Pass NULL to restore the built-in default ("openai:gpt-4o" unless overridden with options(aisdk.default_model = ...)). If new is omitted and runtime options are supplied, only the runtime options are updated.

Usage

set_model(
  new = NULL,
  context_window = NULL,
  max_output_tokens = NULL,
  max_tokens = NULL,
  thinking = NULL,
  thinking_budget = NULL,
  reasoning_effort = NULL,
  reset_options = FALSE
)

Arguments

new	A model identifier string, a LanguageModelV1 object, or NULL.
context_window	Optional context-window override used by sessions created from this default model.
max_output_tokens	Optional maximum output-token metadata override.
max_tokens	Optional default generation token limit.
thinking	Optional default thinking-mode value passed to providers that support it. Logical values are normalized by each provider.
thinking_budget	Optional default thinking budget.
reasoning_effort	Optional default reasoning effort ("low", "medium", or "high").
reset_options	Logical. If TRUE, clears default runtime options.

Value

Invisibly returns the previous default model.

Examples

old <- set_model("deepseek:deepseek-chat")
current <- get_model()
set_model(old)
set_model(NULL)

aisdk documentation built on May 29, 2026, 9:07 a.m.