Free and open source · FTC DECODE 2025-26
Built so Claude never guesses.
Refract is a Claude Code plugin for FTC teams. Every rule verdict, hardware spec, and generated line traces to a cited source, or it abstains.
VS Code / Copilot
Antigravity
Gemini CLIEvery tool checked so far reaches Refract's grounded data, every one, with no exceptions. Some read the skills directly with zero setup; the rest get full access through a plain MCP connection. Full per-tool detail on the compatibility page.
cited, not recalled
Every rule verdict and hardware spec traces to a file actually read that turn, with a URL and a retrieval date you can go re-check yourself.
abstains, not guesses
When a part isn't in the seeded catalog, you get the gap named and the unblocking step, not a confident number that happens to be wrong.
every tool checked
All 8 tools checked so far reach the same grounded data. Five read the skills with zero setup; the rest connect over plain MCP.
Same request. Opposite outcome.
Not a staged demo. This is real output from Refract's own eval suite (TRACEABILITY.md R92/R93): the identical prompt, "write a teleop OpMode for our shooter," run once without Refract and once with ftc-construct.
The failure mode this is built against
Confidence, not question difficulty, is what predicts whether a check gets skipped.
A capable model answers from memory exactly when it feels sure, and that's exactly when a wrong recall does the most damage. Refract puts a deterministic check in front of the confident answer. See the three real incidents that shaped it.
Five skills, one router.
Start with ftc-team-config for anything code-related. Everything else routes from there. Full depth on the skills page.
Confirms your robot's config before any code generation. Doesn't write code itself, hands off to ftc-construct once confirmed.
Writes new OpModes, subsystems, and mechanism features, grounded in real library docs and the hardware catalog. Runs a mandatory rules-and-review check before calling anything done.
Motor specs, gear ratios, part compatibility, encoder ticks. Abstains rather than guesses on a part outside the seeded catalog.
"Is X legal," rule citations, Team Update questions. Every verdict runs a freshness check first and cites verified rule text.
Reviews code that already exists in your repo. Deterministic anti-pattern linting plus structural review grounded in the pattern corpus.
Install
Fastest path, Claude Code:
For VS Code, Copilot CLI, Cursor, Gemini CLI, OpenCode, Codex, or Antigravity, see the compatibility page for exactly what each one needs.
Update
All three steps below are needed. marketplace update alone refreshes the catalog but not what's already installed, a real gap found by an actual reinstall test, not assumed.
/plugin marketplace update refract/plugin uninstall refract-suite@refract/plugin install refract-suite@refract