The .MD file in the repository is your best bet but Bitbucket (formerly Stash) does not have the kind of built-in wiki like GitHub does. Atlassian has it's own separate wiki instance called Confluence (https://www.atlassian.com/software/confluence/) which can be integrated somehow with Bitbucket.
We’ve been building a plugin to integrate Bitbucket Server and Jenkins CI, and I’m excited to announce that our alpha is ready to download and install. It lets you seamlessly configure a Jenkins job ...
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