Step Parts

interface:
  display_name: "STEP Parts"
  short_description: "Find and download STEP files from step.parts"
  default_prompt: "Use $step-parts to find and download a STEP file from step.parts."


MIT License

Copyright (c) 2026 earthtojake

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# step.parts API Reference

## Origins

Default to the API origin `https://api.step.parts`. Use a different origin only when the user supplies another hosted step.parts-compatible API domain. Static HTML pages live on `https://www.step.parts`; GLB and PNG preview URLs in API records point directly at Vercel Blob. STEP URLs are environment-aware and production records use commit-pinned GitHub LFS media. If the API domain does not resolve, treat the hosted service as unavailable and ask for a deployed origin when a live download is required.

## Machine Endpoints

| Endpoint | Use |
| --- | --- |
| `https://www.step.parts/llms.txt` | Human-readable agent guide with endpoint summary and examples. |
| `/v1/parts` | Search, filter, paginate, and retrieve absolute asset URLs. |
| `/v1/parts/{id}` | Fetch one enriched part record by stable id. |
| `/v1/catalog/schema` | JSON Schema, field semantics, result ordering, and family attribute meanings. |
| `/v1/catalog/parts.index.json` | Compact id/name/facet discovery index for cheap lookups before fetching details. |
| `/v1/openapi.json` | OpenAPI 3.1 contract for generating clients/tools. |

## `/v1/parts` Query Parameters

- `q`: tokenized metadata search across id, name, description, category, family, stepSource, productPage, tags, aliases, standard fields, attribute keys, and attribute values. Every token must match.
- `tag`, `category`, `family`, `standard`: repeatable filters. Values may also be comma-separated. Values within one facet are ORed, and selected facet fields are ANDed together.
- `page`: 1-based page number.
- `pageSize`: default `100`, max `500`.

Unfiltered results start with a fixed 100-part showcase, then continue in stable source catalog order. Filtered results are ordered by stable source catalog order.

Examples:

```text
https://api.step.parts/v1/parts?q=M3&tag=screw&page=2
https://api.step.parts/v1/parts?pageSize=100
https://api.step.parts/v1/parts?category=fastener&family=socket-head-cap-screw&standard=ISO%204762
https://api.step.parts/v1/parts?q=lengthMm%2012
```

## Response Fields

`/v1/parts` returns:

- `catalog`: part count, last modified timestamp, catalog checksum, and URLs for schema/OpenAPI.
- `items`: enriched part records with absolute `pageUrl`, `apiUrl`, `stepUrl`, `glbUrl`, and `pngUrl`.
- `page`, `pageSize`, `total`, `totalPages`, `hasNextPage`, `hasPreviousPage`.
- `facets`: available `tags`, `categories`, `families`, and `standards` with counts.
- `filters`: parsed active filters.

Each part record contains:

- `id`: stable snake_case identifier and asset filename base.
- `name`, `description`, `category`, `family`, `tags`, `aliases`.
- `standard`: optional `{ body, number, designation }`.
- `attrib