international-code-of-signals

name	international-code-of-signals
description	Expert on the International Code of Signals (ICOS, Pub. 102, 1969/2003) — encode, decode, and explain maritime signals by any method (flag hoists, flashing light, sound, radiotelephony): single-letter urgent signals, the two-letter General Signal Code, the three-letter Medical Signal Code, procedure signals, Morse, phonetic alphabets, distress and lifesaving signals, MAYDAY/PAN PAN/SECURITE — plus adapting ICOS mechanisms (complete-meaning registries, complements tables, two-phase acks, priority preemption) to inter-agent communication protocol design and to Port Daddy's flag symbology (SIGNAL_FOR_STATE, hoists, alert tiers). Use for signal lookup/composition, flag meanings, signaling procedure, agent message-registry design, or auditing pd maritime UI semantics. NOT for COLREGS right-of-way rules, ship handling (`a-task-analysis-of-pier-side-ship-handli`, a WinDAGs-library skill), radio hardware/frequency regulation, or palette work without signal semantics (`color-theory-palette-harmony-expert`).
license	Apache-2.0
allowed-tools	Read,Grep,Glob,Bash(python3:*)
metadata	{"category":"Domain Knowledge & Protocol Design","tags":["international-code-of-signals","maritime-signaling","signal-flags","agent-protocols","port-daddy-symbology"],"provenance":{"kind":"first-party","owners":["port-daddy"],"source":"Pub. 102, International Code of Signals, US Edition 1969 (Revised 2003), NIMA — parsed corpus in data/signals.json"},"pairs-with":[{"skill":"agent-conversation-protocols","reason":"ICOS supplies the historical design patterns (complete-meaning registry, procedure signals, priority classes) that agent conversation protocols formalize."},{"skill":"agent-interchange-formats","reason":"Complements tables and typed data fields are the ICOS ancestors of interchange schemas; use together when designing fleet message formats."},{"skill":"color-theory-palette-harmony-expert","reason":"Flag-face colors vs semantic state colors need palette discipline when extending pd's maritime UI."}],"io-contract":{"kind":"deliverable","consumes":["[Truncated]","[Truncated]"],"produces":["[Truncated]","[Truncated]"]}}

International Code of Signals

Fluent command of Pub. 102 — the 1969 International Code of Signals — as a working signal book and as a century-hardened protocol-design casebook for agent systems and Port Daddy's maritime symbology.

Use This For

• Decoding or composing any ICOS signal: single letters, two-letter groups (NC, CB 6), medical M** groups, complements, hoists with substitutes, procedure signals.
• Explaining signaling procedure per method: flag hoist etiquette (dip/close-up), flashing-light message anatomy, sound-signal restrictions, radiotelephony calls, MAYDAY/PAN PAN/SECURITE.
• Distress and lifesaving signals: the 14 COLREGS distress signals, shore-to-ship landing signals, breeches-buoy protocol.
• Designing inter-agent message registries, ack semantics, priority classes, or mode-scoped vocabularies on ICOS principles.
• Auditing or extending Port Daddy's flag symbology (SIGNAL_FOR_STATE, hoist combos, alert-tier colors) against the real Code.

Do Not Use This For

• COLREGS navigation rules (right of way, lights, fog conduct) — the Code only touches COLREGS where sound signals overlap.
• Ship handling and maneuvering craft (a-task-analysis-of-pier-side-ship-handli — WinDAGs library, not bundled in this repo).
• Radio spectrum/licensing questions, GMDSS equipment carriage rules.
• Palette or branding work with no signal semantics (color-theory-palette-harmony-expert).

Bundle Contents

Everything shipped with this skill (only this file auto-loads — the rest is here so you know to reach for it):

Path	What it is
data/signals.json	THE ground-truth corpus, parsed from Pub. 102: 26 single-letter signals (+12 numeral-complement forms), 645 two-letter General Code signals + 723 complements, 445 Medical Code signals, procedure signals, Morse, phonetic tables, Complements Tables 1–3, icebreaker session table. Coverage verified against the raw extraction (645/645, 445/445)
scripts/icos_lookup.py	Query CLI over the corpus — exact lookup, hybrid search, spelling, hoists, tables (usage below)
scripts/rebuild_corpus.py	Regenerates data/signals.json from a pdftotext -layout extraction of the Pub. 102 PDF; only needed if the source book changes