spiderbrain

spiderbrain

A committed understanding layer for your repo, and the one command to work with it. A repo tells an AI agent what the code is; it never tells it what matters, what a change reaches, or why anything was built the way it was. spiderbrain fixes that.

• Website: https://spiderbrain.ai
• Format spec + source: https://github.com/aabhisrv/spiderbrain.ai

Give a repo understanding

export SPIDERBRAIN_API_KEY=sb_live_...     # https://spiderbrain.ai/dashboard?tab=keys
npx spiderbrain create

Writes a source-free .spiderbrain/ folder and an AGENTS.md block. Commit both.

Read a repo's understanding (no account needed)

When a repo has a .spiderbrain/ folder, any agent or developer can use it offline:

npx spiderbrain mcp                 # an MCP server for Claude Code / Cursor
npx spiderbrain blast src/db.ts     # what a change here reaches
npx spiderbrain impact              # what your current git diff reaches
npx spiderbrain keystones           # the load-bearing files
npx spiderbrain path a.ts b.ts      # how one file reaches another
npx spiderbrain verify              # folder untampered + current? (CI gate)

Every command takes --json (exit codes: 0 ok, 1 failed, 2 usage, 3 no understanding). No committed folder? The reader falls back to the public registry when the repo's origin has an unofficial brain there.

The pieces

spiderbrain is a thin dispatcher over two independently installable packages:

• @spiderbrain/read — consume: reader, CLI, MCP server. Zero dependencies.
• @spiderbrain/create — produce: fetch your scored brain and write the understanding set.

A CI job that only publishes understanding can depend on @spiderbrain/create alone; an MCP config that only reads can point at @spiderbrain/read. spiderbrain is what you type when you just want the thing.

License

MIT.