One evaluation of the circumstances one vessel is in, under the COLREGS, with three readings. signals: every complete, lawful set of navigation lights self may show, from her fact record (propulsion, activity, position, length, and the other facts in colregs data/facts.json): the applied entries; exempted (relieved by a rel:exempts entry) and overridden (displaced by a superior obligation's rel:overrides) entries, each with the entry that did it; and lawful_displays: {count, relation, options}. relation is "none", "exactly_one" or "any_one_of". A fact record describes a situation, not a fitted vessel: colregs data/facts.json has no equipment fact, so nothing in the input can settle a choice the Rules leave to how the vessel is fitted or what the skipper elects, such as Rule 25(b), the combined masthead lantern a sailing vessel under 20 m may carry, against Rule 25(c), the all-round red over green she may add. When lawful_displays.count is greater than 1, every option is equally lawful, the correct report is all of them, and reporting any one as "the" display for this vessel is wrong. Displays are listed in the order to consider the rules in, most specific concession first, and the first is the one a vessel of that description usually shows. Each option numbers itself "n of count", names the choice entries that distinguish it (chosen) and lists its lights with their own modality, so "shall" and "may" lights in one display are never merged. optional_additions are lawful extras (relation any_subset_of) that do not multiply the display set. Every id carries its paragraph cite, and cited_paragraphs holds the verbatim text of every cited paragraph. appraisal: what Part B requires of self on her own, then against each other vessel (kind of encounter, risk of collision, each vessel's role). indicated: per other vessel, what her observed lights, shapes and sounds say she could be. appraisal and indicated are passed through from colregs-engine as returned, without the cite resolution signals has. Compliance over time is not read yet. Not for navigation. Coverage: COLREGS Part C lights only, international (high seas) text only, lights at night only (no day shapes, no sound signals, no Part B steering rules), evaluated against pre-release colregs data (0.x), whose content is still being checked. Every entry id and paragraph cite in a response is verbatim from the colregs data package; nothing is paraphrased. This tool surface is a 0.0.x preview and will change without notice.

The verbatim text of a COLREGS paragraph from colregs data/rules.json, by its cite as used in every other response here: a paragraph path such as "25(b)" or "26(c)(i)", a bare rule number such as "25" for every paragraph of that rule, or a range such as "24(a)(ii)-(iv)". The text is the International text as transcribed from the USCG amalgamated Navigation Rules; the response names the source and retrieval date. Not for navigation. Coverage: COLREGS Part C lights only, international (high seas) text only, lights at night only (no day shapes, no sound signals, no Part B steering rules), evaluated against pre-release colregs data (0.x), whose content is still being checked. Every entry id and paragraph cite in a response is verbatim from the colregs data package; nothing is paraphrased. This tool surface is a 0.0.x preview and will change without notice.

The definition of one light from colregs data/lights.json, verbatim: name, the Rule 21 paragraph that defines it, colour, character, arc in degrees and placement. Ids are the light ids that evaluate returns in signals, such as "light:sidelights" or "light:all_round"; the "light:" prefix is optional. Arcs use the bearing convention returned alongside. Not for navigation. Coverage: COLREGS Part C lights only, international (high seas) text only, lights at night only (no day shapes, no sound signals, no Part B steering rules), evaluated against pre-release colregs data (0.x), whose content is still being checked. Every entry id and paragraph cite in a response is verbatim from the colregs data package; nothing is paraphrased. This tool surface is a 0.0.x preview and will change without notice.