{"success":true,"version":"v1","request":{"tool":"get_calculator_schema","calculator_id":"length"},"result":{"entity_type":"calculator","id":"length","calculator_id":"length","canonical_url":"https://tttkmbb.com/conversion/length","name":"Length Converter","title":"Length Converter – Metres, Kilometres, Inches, Feet, Yards, Miles and Nautical Miles","category":"conversion","category_name":"Unit Conversion","tool_name":"convert_length","featured_mcp_tool":false,"description":"Converts a length or distance between metric (nm to km), imperial/US (in, ft, yd, mi), nautical and astronomical units using exact NIST factors (1 in = 0.0254 m, 1 mi = 1609.344 m).","use_when":"You need a distance, height or length in a different unit, e.g. miles to kilometres, feet to metres or inches to centimetres.","do_not_use_when":"You need an area (use area), a volume (use volume), or a speed (use speed); for walking distance from step counts use steps-to-distance.","inputs":[{"name":"value","label":"Value","type":"number","required":true,"description":"Amount to convert, expressed in from_unit.","example":5},{"name":"from_unit","label":"From unit","type":"enum","required":true,"values":[{"value":"nm","label":"Nanometre (nm)","aliases":["nanometre","nanometer","nanometres","nanometers"]},{"value":"um","label":"Micrometre (μm)","aliases":["μm","micrometre","micrometer","micrometres","micrometers","micron","microns"]},{"value":"mm","label":"Millimetre (mm)","aliases":["millimetre","millimeter","millimetres","millimeters"]},{"value":"cm","label":"Centimetre (cm)","aliases":["centimetre","centimeter","centimetres","centimeters"]},{"value":"m","label":"Metre (m)","aliases":["metre","meter","metres","meters"]},{"value":"km","label":"Kilometre (km)","aliases":["kilometre","kilometer","kilometres","kilometers","kms"]},{"value":"in","label":"Inch (in)","aliases":["inch","inches"]},{"value":"ft","label":"Foot (ft)","aliases":["foot","feet"]},{"value":"yd","label":"Yard (yd)","aliases":["yard","yards","yds"]},{"value":"mi","label":"Mile (mi)","aliases":["mile","miles","statute mile","statute-mile","statutemile","statute·mile","statute_mile","statute miles","statute-miles","statutemiles","statute·miles","statute_miles"]},{"value":"nmi","label":"Nautical mile (nmi)","aliases":["nautical mile","nautical-mile","nauticalmile","nautical·mile","nautical_mile","nautical miles","nautical-miles","nauticalmiles","nautical·miles","nautical_miles","sea mile","sea-mile","seamile","sea·mile","sea_mile","n.mi","n-mi","n mi","n·mi","n_mi"]},{"value":"fathom","label":"Fathoms (fathom)","aliases":["fathoms"]},{"value":"au","label":"Astronomical unit (au)","aliases":["astronomical unit","astronomical-unit","astronomicalunit","astronomical·unit","astronomical_unit","astronomical units","astronomical-units","astronomicalunits","astronomical·units","astronomical_units"]},{"value":"ly","label":"Light-year (ly)","aliases":["light-year","light year","lightyear","light·year","light_year","light-years","light years","lightyears","light·years","light_years"]}],"description":"Unit of the input value. 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