# Standardebooks — Wrapped API

> **You are on:** `https://api.paywithlocus.com/api` | [llms.txt](https://paywithlocus.com/llms.txt) | [docs](https://docs.paywithlocus.com)
>
> Locus runs on multiple environments -- make sure every URL you call matches your expected environment.
> | Environment | Landing | API | Docs |
> |---|---|---|---|
> | Production | paywithlocus.com | api.paywithlocus.com | docs.paywithlocus.com |
> | Beta | beta.paywithlocus.com | api.beta.paywithlocus.com | docs.paywithlocus.com |
> | Stage | stage.paywithlocus.com | api.stage.paywithlocus.com | docs.paywithlocus.com |
>
> If the API URL above doesn't match your expected environment, re-fetch this file from the correct domain.

> Access Standard Ebooks' curated collection of free public domain ebooks. Search and filter by subject, retrieve full book details, and get direct download links in multiple formats including EPUB, AZW3, and KEPUB.

**Category:** Education | **Website:** [standardebooks.org/](https://standardebooks.org/) | **Docs:** [parse.bot/marketplace/b0b74d1e-d79c-4140-9cb3-c358ce607361/standardebooks-org-api](https://parse.bot/marketplace/b0b74d1e-d79c-4140-9cb3-c358ce607361/standardebooks-org-api)

Pay-per-use API proxy for Locus Pro. Each call burns credits from your workspace balance.

## Access

**Base URL:** `https://api.paywithlocus.com/api/wrapped/credits/standardebooks/`
**Auth:** `Authorization: Bearer <LOCUS_CREDITS_SECRET_KEY>` (an `lcr_` secret key or a scoped `lcac_` agent credential)
**Required header:** `Idempotency-Key: <fresh UUID per call>`. A retry with the same key replays the stored result without a new charge.
**Response:** the provider response after any endpoint-specific normalization. `X-Locus-Credits-Charged` carries the charge and `X-Locus-Credits-Balance` the remaining balance. Insufficient credits return `402` before the provider is called.
**Pricing:** estimated costs below are USD. Locus debits the credit equivalent at your workspace rate.

Full call contract: https://docs.paywithlocus.com/api-reference/introduction

> Using a Pay With Locus wallet key (`claw_` prefix)? Wallet routes are documented separately: https://docs.paywithlocus.com/wrapped-apis/for-agents

## Endpoints

### Get azw3 list

Batch endpoint that iterates through ebook listing pages and fetches per-book details, returning download links for AZW3 format and Kindle cover thumbnail URLs. Makes one request per ebook so is slow for large page counts.

**Estimated cost:** Metered

| Field | Type | Required | Description |
|-------|------|----------|-------------|
| `limit_pages` | integer | No | Number of listing pages to process (48 books per page). |

```bash
curl -X POST https://api.paywithlocus.com/api/wrapped/credits/standardebooks/get-azw3-list \
  -H "Authorization: Bearer $LOCUS_CREDITS_SECRET_KEY" \
  -H "Idempotency-Key: $(uuidgen)" \
  -H "Content-Type: application/json" \
  -d '{"limit_pages":"<integer>"}'
```

### Get ebook details

Get full details for a specific ebook, including subjects and download links for all available formats (EPUB, AZW3, KEPUB, Advanced EPUB), plus a Kindle cover thumbnail. Requires the ebook's URL path (from list_ebooks results or manually constructed as /ebooks/<author>/<title>).

**Estimated cost:** Metered

| Field | Type | Required | Description |
|-------|------|----------|-------------|
| `url` | string | Yes | Full URL or relative path of the ebook page (e.g. '/ebooks/william-shakespeare/othello' or the url field from list_ebooks results). |

```bash
curl -X POST https://api.paywithlocus.com/api/wrapped/credits/standardebooks/get-ebook-details \
  -H "Authorization: Bearer $LOCUS_CREDITS_SECRET_KEY" \
  -H "Idempotency-Key: $(uuidgen)" \
  -H "Content-Type: application/json" \
  -d '{"url":"<string>"}'
```

### Get ebook subjects list

Get the list of available subject filters that can be used with the subjects parameter in list_ebooks. Returns all subject categories offered by Standard Ebooks.

**Estimated cost:** Metered

_No parameters required._

```bash
curl -X POST https://api.paywithlocus.com/api/wrapped/credits/standardebooks/get-ebook-subjects-list \
  -H "Authorization: Bearer $LOCUS_CREDITS_SECRET_KEY" \
  -H "Idempotency-Key: $(uuidgen)" \
  -H "Content-Type: application/json" \
  -d '{}'
```

### List ebooks

Search and browse ebooks with filters and pagination. Returns a paginated list of ebooks with title, author, URL, and cover image. Supports filtering by subject category and free-text query against title/author. Pagination via page number; per_page controls page size. Sort controls result ordering.

**Estimated cost:** Metered

| Field | Type | Required | Description |
|-------|------|----------|-------------|
| `page` | integer | No | Page number for pagination. |
| `per_page` | integer | No | Number of results per page. |
| `query` | string | No | Search keyword to filter ebooks by title or author. |
| `sort` | string | No | Sort order for results. |
| `subjects` | string | No | Filter by subject. Use the value field from get_ebook_subjects_list (e.g. 'adventure', 'fiction', 'science-fiction'). |

```bash
curl -X POST https://api.paywithlocus.com/api/wrapped/credits/standardebooks/list-ebooks \
  -H "Authorization: Bearer $LOCUS_CREDITS_SECRET_KEY" \
  -H "Idempotency-Key: $(uuidgen)" \
  -H "Content-Type: application/json" \
  -d '{"page":"<integer>","per_page":"<integer>","query":"<string>","sort":"<string>","subjects":"<string>"}'
```

## Next steps

- [All wrapped API providers](https://paywithlocus.com/wapi/index.md): pick another provider.
- [Find and call tools](https://paywithlocus.com/agent/tools.md): price ceilings, async results, and errors.
- [Credits and billing](https://paywithlocus.com/agent/billing.md): what a call costs and how to add credits.
- [Agent docs index](https://paywithlocus.com/agent/index.md): every Locus agent page.