wp-includes/php-ai-client/src/Messages/DTO/MessagePart.php:135Gets the thought signature.
string|null public function getThoughtSignature(): ?string { return $this->thoughtSignature; }Introduced in 1.3.0. Unchanged from 7.0.4 through 7.1.0.
Signature, return type and hooks compared across 2 parsed releases.
src/wp-includes/php-ai-client/src/Messages/DTO/MessagePart.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.