Pāṇini sūtras

The la denoting the agent, when the action affecting the agent is similar to the action which affects the object, is treated as if it were a la denoting the object.

1. karma+vatकर्म+वत्

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   kक्	karmanकर्मन्	karmaकर्म	object	karmकर्म् + plus aअ
   vव्	vatवत्	vatवत्	equally	vatवत्

2. karmaṇāकर्मणा

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   kक्	karmanकर्मन्	karmaṇāकर्मणा	object	karmकर्म् + plus aṇ&#अण्&#

3. tulya+kriyaḥतुल्य+क्रियः

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   tत्	tulyaतुल्य	tulyaतुल्य	like	tulyतुल्य् + plus aअ
   kक्	kriyāक्रिया	kriyaḥक्रियः	action	kriyक्रिय् + plus aḥअः

Anuvṛtti

1. kartariकर्तरि 3·1·68

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   kक्	kartṛकर्तृ	kartariकर्तरि	agens	kartकर्त् + plus ariअरि