type: Literal["web_search", "web_search_2025_08_26"]

The type of the web search tool. One of web_search or web_search_2025_08_26.

One of the following:

"web_search"

"web_search_2025_08_26"

external_web_access: Optional[bool]

Allow live internet access for web search. Defaults to true when omitted. When false, the web search tool runs in offline/cache-only mode and will not fetch new external content.

filters: Optional[Filters]

Filters for the search.

allowed_domains: Optional[List[str]]

Allowed domains for the search. If not provided, all domains are allowed. Subdomains of the provided domains are allowed as well.

Example: ["pubmed.ncbi.nlm.nih.gov"]

search_context_size: Optional[Literal["low", "medium", "high"]]

High level guidance for the amount of context window space to use for the search. One of low, medium, or high. medium is the default.

One of the following:

"low"

"medium"

"high"

user_location: Optional[UserLocation]

The approximate location of the user. If omitted or null, defaults to the United States. To avoid this fallback, pass {"type": "approximate"} without location fields. To localize results, provide the relevant location fields.

city: Optional[str]

Free text input for the city of the user, e.g. San Francisco.

country: Optional[str]

The two-letter ISO country code of the user, e.g. US.

region: Optional[str]

Free text input for the region of the user, e.g. California.

timezone: Optional[str]

The IANA timezone of the user, e.g. America/Los_Angeles.

type: Optional[Literal["approximate"]]

The type of location approximation. Always approximate.