Tamil Sage Agasthiyar is the founder of varmakkalai who lived in the south-pothigai mountains (Kutralam) which is in the southern part of Tamil Nadu ruled by Pandiya kings. His period is said to be before "Sangam Literature". He is also the founder of secret art called Nokkuvarmam and Meitheendakkalai. There is temple for Agasthiyar in Ambasamudram in Tamil Nadu, also still the stone on which he meditated is in the same temple. As per a stanza from a song written by Siddhar (Sage) Agasthiyar which indicates who are all the fake masters.
"நீனிலத்தில் தன்னைத் தானெ உயர்த்திபேசி தனக்கு நிகர் வேரொருவர் இல்லையென்று கூரித் திரிவாரே ! இவர்கள் நரம்பு தசை எலும்பு வர்மம் துணுக்கெலும்பு துண்டுகளின் துகை காணாரே"
"Neenilathil thannai thane uyarthipesi thanakku nigar veroruvar illayendru kuuri thirivarae ! Ivargal narambu thasai elumbu varmam thunukelumbu thundukalin thugai kaanaarae"
This is the stone in which Sage Agaasthiyar meditated and it is still lying in the Agastheeswarar Temple in Ambasamuthiram, Thirunelveli District of Tamil Nadu. His period is said to be that of Sangam literature, which is more than 5000 Years ago. He has gifted Lord Rama the Asthram which was used to kill Ravana in Ramayanam. Also he is the same person who gifted the "Brahmasaras" asthram to sage Dronachariyar, who then gave it Ashwathama. It is the last Asthram to be used in Mahabharatam which was redirected to Abimanyu's son while he was fetus.
There are few references in Mahabharatham & Ramayanam where varmakkalai and meitheendakkalai has been used. During the battle Lord Krishna has signaled Bhima to strike Dhuruyodhana in his thighs in an important varmam point.
Also in Ramayanam when Lord Hanuman traveled to Lanka to see Seetha, he used Meitheendakkalai and then made all of the soldier to faint for few minutes to pass through to Ashokavanam.
Lord Hanuman, Siva & Murugan has strong link to Varmakkalai and we may not be able to quote all those references in this site.