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+`bcs` is a command-line utility for searching a git-based codebase that syntax-highlights the results. Only files included in the git tree are searched. (This avoids wasting time searching through build output files, autogenerated source code that's not checked in, etc.)
+
+Grab the latest version: <https://git.semicolin.games/semicolin/sneak/src/branch/master/tools/scripts/bcs.sh>
+
+It expects you've already installed the `highlight` program on your system (`sudo apt install highlight` or similar).
+
+Usage:
+```
+bcs.sh [-i] [-f/--file FILE_PATTERN] [-x/--extension EXTENSION] [-C/--context NUM_LINES] [-t/--tree TREE_NAME] QUERY
+
+Arguments:
+  -i  ignore case in searching for matches
+  -f  pattern to match filenames against
+  -x  file extension that must be matched
+  -C  number of lines of context to include before and after each match (default: 3)
+  -t  tree-ish id (as per `git ls-tree`)
+```
+
+Some examples:
+```
+Search for the token "Vector3" in files whose names contain "Line":
+$ bcs.sh --file Line Vector3
+
+Search for "new vector3" on the same line (in that order but not necessarily next to each other; case-insensitive):
+$ bcs.sh -i new vector3
+
+Show 10 lines of context before & after each match:
+$ bcs.sh -C 10 new Vector3
+
+Search for "sprite" only in files ending in ".py":
+$ bcs.sh -x py sprite
+
+Search for "spritebatch" in .cs files with "World" in their names (case-insensitive):
+$ bcs.sh -i -x cs -f World spritebatch
+
+Search for "SpriteBatch" in .cs files under MonoGame.Framework/ in the tree named "develop" (the main branch that MonoGame develops on):
+$ bcs.sh --tree develop -x cs -f MonoGame.Framework/ SpriteBatch
+```
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