Browse the LEGO theme hierarchy. With no input, returns all top-level themes with set counts. With a theme name, returns its sub-themes and sets. Use this to explore what LEGO themes exist or drill into a specific theme.

Compare 2 to 4 LEGO sets side by side. Shows piece count, year, theme, minifig count, and shared parts between sets. Use this when someone is deciding between sets or wants to know what parts overlap.

Find community alternate builds (MOCs) that can be made from a specific LEGO set's parts. Use this when someone wants to know what else they can build with parts they already own.

Find which LEGO sets contain a specific part, optionally in a specific colour. Use this when a builder wants to know where to source a particular brick. Results sorted by quantity (most pieces first).

Get complete details for a specific LEGO minifigure including every set it appears in. Use this when you know a minifig name or fig number and want to find which sets include it.

Get complete details for a specific LEGO part including available colours and mold/print variants. Use this when you know a part number (like 3001) and need its specifications, colour availability, or related parts.

Get complete details for a specific LEGO set including piece inventory, minifigures, and theme. Use this when you know a set number (like 75192-1) or set name and need full information. Returns inventory grouped by part category.

Search for LEGO minifigures by name. Use this when looking for specific characters or minifig types. Returns fig numbers and names: use get_minifig for full details and set appearances.

Search for LEGO parts by name, category, colour, or material. Use this when looking for specific brick types, plates, tiles, or other elements. Returns part numbers and names: use get_part for full details.

Search for LEGO sets by name, theme, year, or piece count. Use this when looking for sets matching specific criteria. Returns a summary list: use get_set for full details on a specific set.