Command line description.

OPTIONS:
        M=##     Margin (default 50)
        N=##     Number of mismatches allowed (default 0)
        W=##     Word size (default 7)

(Pasted verbatim from http://www.ncbi.nlm.nih.gov/genome/sts/epcr.cgi)

"Word" (W) is to set exact match of W bases at the 3' end of each primer. The default is
set to 7. The value of W can be reduced from the default value to reduce the chance of
missing a true STS, but speed is sacrificed in the process.

"Margin" (M) is to allow an e-PCR product size to be within M bases margin of the
previously reported PCR product size. The default value is set to 10.

"Mismatch" (N) is to allow mismatches in each primer sequence, but not within the W
bases from the 3' end. Increasing the value of N will allow more potential STSs to be found,
but doing so may result in some false positives being reported.