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  "title": "A tide window is a promise · Harbor tides",
  "description": "Why the API answers with the hours a draft clears, and never with a table to read by hand.",
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        "cta": { "href": "/contact", "label": "Talk to the harbor" }
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          "tag": "Windows",
          "dateline": {
            "date": "2026-10-20",
            "read": { "minutes": 3, "unit": "min read" }
          },
          "title": "A tide window is a promise",
          "dek": "Why the API answers with the hours a draft clears, and never with a table to read by hand."
        },
        "body": "A tide table lists heights. A crew needs hours: when the water over the sill is deep enough for the keel, and when it stops being so.\n\n## From heights to hours\n\nThe window route takes a berth and a draft. It adds the charted depth to each predicted height, keeps the hours the sum clears the draft plus a margin, and returns the first and last.\n\n```json\n{ \"draft\": 3.2, \"opens\": \"08:05\", \"closes\": \"12:50\" }\n```\n\n## Why a promise\n\nA window names its datum and its station, so a crew can check it. When the gauge disagrees with the prediction, the next call says so."
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        "blurb": "Tide tables for every berth, as one API.",
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        "note": ["Harbor tides is a worked example on mdxui.dev, not a customer.", "Rendered by @mdxui/site. Forms here do not send."]
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