doc updates

zokrates_book/src/concepts/stdlib.md

@@ -51,7 +51,7 @@ where `G` is the chosen base point of the subgroup and `*` denotes scalar multip
 import "signatures/verifyEddsa.code"
 ```
 
-Verifies an EdDSA Signature. Checks the correctness of a given EdDSA Signature `(R,S)` for the provided public key `A` and message `(M0, M1)`.
+Verifies an EdDSA Signature. Checks the correctness of a given EdDSA Signature `(R,S)` for the provided public key `A` and message `(M0, M1)`. Check out this [python repository](https://github.com/Zokrates/pycrypto) for tooling to create valid signatures.
 
 ### Packing / Unpacking
 

zokrates_stdlib/stdlib/ecc/edwardsScalarMult.code

@@ -1,9 +1,11 @@
 import "ecc/edwardsAdd.code" as add
 import "ecc/edwardsOnCurve.code" as assertOnCurve
-// Function that implements scalar multiplication for a given base point
+// Function that implements scalar multiplication for a fixed base point
 // Curve parameters are defined with the last argument
+// The exponent is hard-coded to a 256bit scalar, hence we allow wrapping around the group for certain
+// curve parameters. 
 // Note that the exponent array is not check to be boolean in this gadget
-// https://github.com/zcash-hackworks/sapling-crypto/blob/master/src/jubjub/fs.rs#L555
+// Reference: https://github.com/zcash-hackworks/sapling-crypto/blob/master/src/jubjub/fs.rs#L555
 def main(field[256] exponent, field[2] pt, field[10] context) -> (field[2]):
 
     field[2] infinity = [context[2], context[3]] 

zokrates_stdlib/stdlib/signatures/verifyEddsa.code

@@ -9,6 +9,9 @@ import "ecc/edwardsOrderCheck.code" as orderCheck
 ///
 /// Checks the correctness of a given EdDSA Signature (R,S) for the provided
 /// public key A and message (M0, M1).
+/// This python repo provides the tooling for creating valid signatures:
+/// https://github.com/Zokrates/pycrypto
+///
 /// For more information see:
 /// https://en.wikipedia.org/wiki/EdDSA
 /// https://eprint.iacr.org/2015/677.pdf