Return the official legislative reasoning (Gesetzesbegründung / explanatory memorandum from a Bundestags-Drucksache) for a specific German federal provision — the source for genetic/historical interpretation: what the legislator intended with this norm.

It answers questions that turn on a norm's purpose (ratio legis / 'why does this rule exist'), the meaning of an unclear or undefined term, whether a regulatory gap is planwidrig (grounds an analogy) or a deliberate silence (grounds an Umkehrschluss), or what a specific amendment was meant to achieve — the everyday uses of materials in an Auslegung or a Schriftsatz. Weight: the Begründung is strong evidence of legislative intent but not binding, and the statutory wording stays the outer limit of any reading.

Pass a provision like '§ 823 BGB' or 'Art. 87a GG'. Returns the linked Begründungs-Abschnitte newest first, each with its 'BT-Drs.' Fundstelle, the reasoning text, and the other norms the same change amended ('target_norm_keys'). Complements legal_find_citing_decisions (how courts apply a norm) with the drafting intent behind it. Covers amendments since 1949 to German federal law (gesetze-im-internet corpus) only; an unknown or non-German provision returns no materials. Excerpts are prepared from the Bundestag-extracted text, not the original PDF.