Trail-code is a free, open-source tool (MIT license, over 10,000 GitHub stars) that builds a map of your code: every file, every function, and who calls what. Claude Code gets pointers to the matching files with each prompt, so it stops opening file after file to find its way.
Here's why it matters, how to install it, what the numbers say, and the catch.
Why Claude gets lost
Every new task, Claude starts without a picture of your project. It searches, opens a file, follows an import, backs out and tries again. That rediscovery burns tool calls, tokens and time, and it happens again next session.
Trail-code builds the picture once, on your machine, with no model and no API key, and keeps it current when your code changes.
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Get the full setup steps + the copy-paste setup prompt
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Unlocks: Step 1: install it · Step 2: what changes · What the numbers say · The catch · Sources
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