Configuration

Everything lives in the indexnowkit/yii3 block of your params (config/common/params.php), merged over the package's config/params.php. Keys mirror the family-wide schema of indexnowkit/core (configuration.md there); the blocks marked Yii3 are handled by this package. Verify with ./yii indexnow:check; ./yii indexnow:config prints the effective result with the keys masked.

Core keys

The package reads four variables itself ($_ENV, $_SERVER, getenv()): INDEXNOW_KEY, INDEXNOW_PREVIOUS_KEY, INDEXNOW_BASE_URL, INDEXNOW_DRY_RUN. Anything else is a literal in the block.

Key	Default	Meaning
enabled	true	kill switch; false = nothing is sent, changes are logged at debug
key	INDEXNOW_KEY	the IndexNow key, [A-Za-z0-9-]{8,128} (./yii indexnow:key:generate)
previous_key	INDEXNOW_PREVIOUS_KEY	the key before a rotation: its file is still served, nothing is submitted under it
key_location	—	full URL of the key file when it is not https://<host>/<key>.txt
base_url	INDEXNOW_BASE_URL	origin for URLs generated outside web requests (console commands)
hosts	[]	host => key or host => ['key', 'key_location', 'base_url', 'engines', 'previous_key']
strict_hosts	false	skip URLs of hosts outside base_url / hosts instead of sending them under the default key
environment	YII_ENV (then APP_ENV)	feeds the non-production dry-run safety net and the check staging error
production_environments	['prod', 'production']	environments where a missing key is an error, not dry-run
dry_run	INDEXNOW_DRY_RUN, else auto	log the request instead of sending it; unset outside production with a key = check fails
max_url_length	2048	longer URLs are invalid_url
engines	['api']	api, yandex, bing, naver, seznam, yep, internetarchive, amazon, an endpoint URL or an alias
engine_aliases	[]	alias => endpoint URL
locale_hosts	[]	locale => host for rules with locales and no host
dispatch	sync	sync (after the response), none (collect, never send); no queue until yiisoft/queue is stable
debounce.per_url	600	seconds a URL is not resubmitted; 0 = off
debounce.store	Psr\SimpleCache\CacheInterface	a container id of a PSR-16 cache, memory, none
debounce.key_prefix	indexnowkit_	cache key prefix (also the 403 counter and the robots cache of verify)
throttle.max_requests_per_minute	60	per process
http.timeout	10	seconds
http.client	null	a container id of a PSR-18 client; null = discovery
key_file.enabled	true	serve /<key>.txt through the package's route
key_file.cache_max_age	300	Cache-Control: max-age of the key file
retry.*, batch.max_urls, logging.*, normalizer.*, collector.*, resolver.*, forbidden_escalation	core defaults	see the core reference

Yii3 keys

Key	Default	Meaning
key_file.pattern	/{key:[A-Za-z0-9-]{8,128}}.txt	the route pattern of the key file (yiisoft/router); the key argument is the key
router.locales	[]	the list locales: 'all' on a rule expands to
router.locale_parameter	_language	the route argument the locale is passed as; a route whose pattern lacks it gets it as a query parameter
active_record.enabled	true	false = the #[IndexNowEvents] hooks and the models list are inert; submit() and the commands still work
active_record.namespaces	['App\Model', 'App\Entity']	where a short class name of indexnow:submit-record / indexnow:explain is looked up
active_record.models	[]	classes hooked without #[IndexNowEvents] (they still need EventsTrait); the package's bootstrap calls IndexNow::observe() for each
logging.category	indexnow	the category context of every log line (what yiisoft/log targets filter on)
checks	[]	container ids of Check\CheckInterface implementations to append to indexnow:check
sitemap.*	—	the block of indexnowkit/sitemap (its configuration); ignored without the package
verify.*	—	the block of indexnowkit/verify (the pre-flight GET before every submission); ignored without the package
history.*	—	the block of indexnowkit/history; history.pdo.service names a ConnectionInterface id of the container, history.pdo.dsn a database of its own; ignored without the package

What is not an option

Replacing a piece of the core (the transport, the debounce store, the dispatcher, the URL resolver, the submission store, the clock) is a container definition, not a params key: every interface is defined by the package's config/di.php and the application's di/ wins (extending.md).

Invalid values

The block is validated at runtime (values come from .env): an unknown key is a warning naming the dotted path (debounce.per_urls), an invalid value is one critical line naming ./yii indexnow:check and IndexNow runs disabled until it is fixed. Nothing throws from a save or a listener. indexnow:check and indexnow:config use the strict path and print the exact error.

Merging

yiisoft/config replaces a whole top-level key of a group unless the application lists the group in RecursiveMerge (configuration.php of the template does for params). Without the recursive merge your block replaces the package's entirely; the package then applies its own defaults (dispatch, key_file.pattern, router.locale_parameter, logging.category) to what your block leaves out, so a minimal block works either way.