Atreya is considered to be the first systematic propounder of the science of healing. Caraka is illustrious as the redactor of the original tantra of Agnivesa.
Krsna Atreya's (also known as Punarvasu) teachings on the art of healing was recorded by Agnivesa. Agnivesa codified the knowledge and arranged it in the form of a Treatise which forms the basis of "The Caraka Samhita". Krsna Atreya expounded the science of Kāyā-Cikitsā to his six pupils among whom Agnivesa stands out. His intellect was superior to his co-students and his treatise was applauded by the sages as the most authoritative. His six disciples were:
Agnivesa was equally adept in the science of war as with that of medicine. He studied archery under Bharadwaja and Agastya and that Bharadwaja gave him the Agneyastra which Agnivesa gave to his pupil Diona. This Astra was called Brahmasirah.
Significant role of the Sage Agnivesa
Agnivesa became the foremost compiler of the science due to his deeper understanding of the materials vs his peers. Not only was he considered to be the most brilliant among the disciples but his compilation received the approval of the committee of experts which declared it to be the best of all and since then it has become the authoritative text-book on the science of healing.
Usage of Name Synonyms
Agnivesa was also known as Hutasa, Hutasavesa, Vahnivesa Hutasa and Vahni which are the synonyms of Agni and the later authors substituted the synonyms for the purpose of variation. The commentator Cakrapani while beginning the benedictory verse refers to Agnivesa by one of these other names. Even in Charaka Samhita, multiple names of Agnivesa are used i.e., Vahnivesa 
The Agnivesa-tantra originally consisted of 12,000 verses. Unfortunately, Agnivesa-tantra in the original form is not available at present. Despite some contraversy to the contrary, it is likely that he finished the treatise as there are references to it throughout the Caraka Samhita. Further, there are a few contradictory statements throughout the text that have furthered this confusion. For example, in the Siddhi-sthana , Drdhabala describes the meeting of the learned sages under the presidentship of Atreya implying that the Agnivesa-tantra was available in Drdhabala's time. However, a few statements of Drdhabala has led some people to think that Agnivesa-tantra was not available in his time.
Redaction of the Agnivesa Tantra
The original seventeen chapters and the sections on Pharmaceutics and Success in Treatment in the treatise composed by Agnivesa and revised by Caraka have not been found. However, Drdhbala added seventeen chapters in the section on therapeutics and also the two sections of Pharmaceutics and Success in Treatment in Caraka Samhita by culling his data from various treatises on the science.
Drdhbala was a redactor, not a commentator and as such, he consulted all the available treatises in order to revise and up-date the text. It is common practise not to name basic text which was being redacted as it is taken as the basis for the redaction.
As a result, there is some ambiguity as to whether these seventeen chapters are based on Agnivesa Tantra.
Critical examinations of the redacted text and detailed review of all available internal and external evidence indicates that the original text of Agnivesa existed as the basic text for Drdhabala and that a certain portion of the redacted text of Caraka was not available.
The style and language of the original texts of Agnivesa, Caraka and Drdhabala can be distinguished on minute examination of the text. Now, we find that there is a mixture of the styles and diction in nearly all the chapters and hence one is led to the natural conclusion that Agnivesa-tantra did exist in the time of Drdhabala.
Agnivesa tantra existed upto and well after Vagbhata is amply supported by various facts. Jejjata, a pupil of Vagbhata quotes some verses from Agnivesa tantra. These verses are not found in the Caraka Samhita and hence he must have quoted from the original Agnivesa tantra. Tisata, son of Vighbala in his Cikitsa mentions Agnivesa as a distinct authority which implies that the Agnivesa-tantra existed in his time. Below mentioned are the few evidences that support this belief:
- Cakrapani, the commentator of Caraka Samhita who flourished in the 11th century CE cites pharmaceutical preparations which are not found in the Caraka Samhita but are in the Agnivesa-tantra
- There are few recipes of Vandya from Agnivesa-tantra are quoted by Sodhala. Sodhala lived in the 12th Century CE
- Kanthadatta, the commentator on Vrnda's Siddhayoga who flourished in the 13th century A. D. has stated few verses which are also not found in the Caraka Samhita and hence it can be presumed that they have been taken directly from the Agnivesa-tantra itself.
- Sivadasa Sen who lived in the I5th century CE quotes Agnivesa-tantra (verse is not found in Caraka Samhita)
- After that period no more citations from the Agnivesa-tantra are available except one suggestive reference by Gangadhar Sastri in the 19th century CE.
Besides this premier work on Ayurveda, several other works are ascribed to Agnivesa. They are:
- Anjana Nidana, a treatise on diseases of the eye. He is also quoted by Vagbhata, Bhavamisra, Tisata and Rudra-bhalla and other authors. There are two or three commentaries written on this book.
- Nidanasthana, a treatise on pathology also stands in the name of Agnivesa.
Agnivesa, Son of Satyaka
One Agnivesa, the son of Satyaka, is mentioned in Majjham Nikaaya to have taken part in the philosophical debate with Gautama Buddha. He was the pupil of Atreya and hence he flourished during the period of Atreya i.e during the Satapatha period. We may briefly enumerate the point that support our placing him in the Satapatha period, apart from the argument of his contemporaneity with Atreya.
- He lived before Panini as we find references to Taxilla in Panini, while reference of Taxilla is absent in Agnivesa Samhita. No author of the versatility of Agnivesa could afford to neglect mentioning Taxilla if it were a flourishing center of medical learning in his time
- In the Paanini Sutra, Jatkarna, Parasara and Agnivesa are all names of physicians that occur together indicating that Agnivesa lived before Panini's period. Jataakarna and Parisara were co-students of Agnivesa
- Hemaadulaksana quotes from Silhotra, a last of Ayurvedic authors. In it Agnivesa, Harita, Ksarapani and Jatu karna are mentioned and were co-students
- Satapatha Brahmana refers to the descendants of Agnivesa
- In Siddhisthan 12th chap, verse 53 Agnivesa is referred to as Vahnivesa
- for exmaple, by Indukara, commentator of Astanga Sangraha
- 4th chapter of the Caraka Samita
- Satapatha means stupor
- The Caraka Samhita published by Shree Gulabkunverba Ayurvedic Society, Jamnagar, India