# Craft & Maker Calc – Half-Square Triangle (HST) Cut Size

> Craft & Maker Calc – Half-Square Triangle (HST) Cut Size is a paid API for AI agents from craft-calc.x402tookit.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-30).

Calculates the cut square size needed for half-square triangles (HST) using the two-at-a-time or four-at-a-time method, given the desired finished HST size in inches.

## Facts

- Endpoint: GET https://craft-calc.x402tookit.com/hst-size?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/craft-maker-calc-half-square-triangle-hst-cut-size-a5a6b4e5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_I6OqY17wAWRPjaxfGKtv5

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability craft-maker-calc-half-square-triangle-hst-cut-size-a5a6b4e5
```

Example prompt: What size squares do I need to cut for half-square triangles that finish at 3.5 inches using the two-at-a-time method? I need 60 HSTs total.

## When to prefer this

Use this endpoint when a quilter or sewist needs to calculate fabric cut sizes for half-square triangles (HSTs) from a known finished size, supporting both the two-at-a-time and four-at-a-time cutting methods with results rounded to the nearest eighth of an inch — the standard unit for quilting measurements.

## Known failure modes

- Missing required finishedInches parameter returns an error
- Invalid or non-numeric finishedInches value causes a validation error
- Unrecognized method value (anything other than 'two' or 'four') may fall back to default or error
- Very small finishedInches values may produce impractical cut sizes
- Payment failure (x402) if USDC balance is insufficient

## How this service works

Cut size of squares for half-square triangles (two-at-a-time or four-at-a-time) from the finished size, in eighths.

## Output

Returns the cut square size in decimal inches and rounded to the nearest eighth of an inch, the unfinished HST size, the seam allowance added, the number of HSTs produced per pair of squares, and (if unitsNeeded is provided) the total number of pairs and squares to cut.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "finishedInches"
     ],
     "properties": {
      "method": {
       "type": "string",
       "description": "two (default; each pair of squares makes 2 HSTs) or four (each pair makes 4 HSTs)"
      },
      "unitsNeeded": {
       "type": "integer",
       "description": "How many HSTs you need, to count the squares"
      },
      "finishedInches": {
       "type": "number",
       "description": "Finished size of one HST in the quilt, in inches"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "asOf": {
       "type": [
        "null",
        "string"
       ]
      },
      "method": {
       "type": [
        "null",
        "string"
       ]
      },
      "source": {
       "type": [
        "null",
        "string"
       ]
      },
      "reasons": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "summary": {
       "type": [
        "null",
        "string"
       ]
      },
      "verdict": {
       "type": [
        "null",
        "string"
       ]
      },
      "degraded": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "disclaimer": {
       "type": [
        "null",
        "string"
       ]
      },
      "notChecked": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "squaresToCut": {
       "type": [
        "null",
        "number"
       ]
      },
      "finishedInches": {
       "type": [
        "null",
        "number"
       ]
      },
      "pairsOfSquares": {
       "type": [
        "null",
        "number"
       ]
      },
      "cutSquareInches": {
       "type": [
        "null",
        "number"
       ]
      },
      "hstPerPairOfSquares": {
       "type": [
        "null",
        "number"

… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/craft-maker-calc-half-square-triangle-hst-cut-size-a5a6b4e5/health.json
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