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CaptainsGround
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Provenance

Every answer traces to a primary source

We don’t generate facts from training data — we generate explanations from cited federal regulations and public-domain mariner texts. Here’s the corpus behind every lesson, drill, and flashcard.

6,263

Citations indexed

6,263

Source chunks

100%

Embedded

9

Primary sources

Live counts, refreshed hourly.

Proof

What a citation looks like in practice

Answer a real drill question and the explanation opens with the rule it tests. The reference is a link, and it resolves.

Rule 15 — Crossing Situation

In a crossing situation between two power-driven vessels under the Inland Rules, the give-way vessel shall, if circumstances admit, take which specific action with respect to the stand-on vessel?

Three things every citation carries

The document
33 CFR 83.34(a) — the section, not the part.
The retrieval date
When we last pulled that text, shown on the source row below.
A resolvable link
It opens the passage. A citation that stops resolving fails the build before the answer can ship.

Publishing principles

Three rules, stated plainly

A fluent explanation is not enough. CaptainsGround keeps source retrieval, generation, validation, and correction as separate steps so an answer can be traced back to the rule that supports it.

01

Start with primary text

The generator receives retrieved chunks from 33/46 CFR, COLREGs, the Inland Rules, Bowditch, or USCG manuals. Each stored citation keeps the canonical source identifier.

02

Keep the citation resolvable

The citation audit checks that stored citations still resolve to corpus text. Source refreshes preserve older versions so an existing citation does not silently disappear.

03

Judge the finished artifact

A separate validator sees the answer and its source chunks, not the generator prompt. Drill questions that fail the source, answer, or ambiguity checks are not published.

Corrections stay traceable

If an answer and its cited rule disagree, email [email protected]. We check the source text, correct the artifact, and run it through validation again. The about page explains who operates the site and how to reach us.

Last updated: July 13, 2026

Nine primary sources, listed in full

Filter by source family. Everything here is federal regulation or public-domain text — verifiable, not paraphrased.

Showing 9 of 9 primary sources, all of them.