shabda pramana (Devanagari: शब्द प्रमाण ISO15919: śabda pramāṇa) means evidence of those words (shabda) which are irrefutable.
Only Vedas offer the shabda pramana as they are the eternal law of God. So, Vedas are the final evidence.
Other scriptures Puranas, Smritis, Darshan Shastra, Itihas etc can be