{"id":"leaf-serialized-overhead-is-7-bytes","text":"Every leaf page has a fixed 7-byte overhead (3B header via `HEADER_FMT = '>BH'` + 4B `next_sibling` pointer) before any key-value entries, setting the usable capacity to `page_size - 7` bytes.","truth_value":"IN","source":"entries/2026/05/29/topic-page-overflow-and-split-mechanics.md","source_url":"","source_hash":"","justifications":[],"dependents":[],"metadata":{},"explanation":{"steps":[{"node":"leaf-serialized-overhead-is-7-bytes","truth_value":"IN","reason":"premise"}]}}