# PubMed Central — 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.

> Search millions of full-text biomedical research articles and access their metadata, citations, and related papers from PubMed Central. Find articles by topic, discover similar research, explore journal collections, and retrieve detailed citation information to support your literature review and research.

**Category:** Healthcare | **Website:** [pmc.ncbi.nlm.nih.gov/](https://pmc.ncbi.nlm.nih.gov/) | **Docs:** [parse.bot/marketplace/6421b0b5-552e-4b64-b57a-420e94666d03/pmc-ncbi-nlm-nih-gov-api](https://parse.bot/marketplace/6421b0b5-552e-4b64-b57a-420e94666d03/pmc-ncbi-nlm-nih-gov-api)

Pay-per-use API proxy. Each call is automatically billed to your wallet in USDC.

## Access

**Base URL:** `https://api.paywithlocus.com/api/wrapped/parse-pmc-ncbi-nlm-nih-gov-api-6421b0b5/`
**Auth:** `Authorization: Bearer <LOCUS_API_KEY>`

## Endpoints

### get_article

Retrieve full article content by PMC ID. Returns the article title, abstract, structured body sections (keyed by section title), authors with affiliations, and a list of cited references. Fetches the XML full-text from NCBI efetch and parses it.

**Estimated cost:** Metered

| Field | Type | Required | Description |
|-------|------|----------|-------------|
| `pmcid` | string | Yes | PMC ID (e.g., 'PMC4728819' or '4728819') |

```bash
curl -X POST https://api.paywithlocus.com/api/wrapped/parse-pmc-ncbi-nlm-nih-gov-api-6421b0b5/get_article \
  -H "Authorization: Bearer YOUR_LOCUS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"pmcid":"<string>"}'
```

### get_article_citations

Get articles in PMC that cite a specific article. Uses NCBI elink's pmc_pmc_citedby linkname to find citing articles, then returns up to 50 summaries with PMC IDs, titles, journals, and publication dates.

**Estimated cost:** Metered

| Field | Type | Required | Description |
|-------|------|----------|-------------|
| `pmcid` | string | Yes | PMC ID to find citations for (e.g., 'PMC7828565' or '7828565') |

```bash
curl -X POST https://api.paywithlocus.com/api/wrapped/parse-pmc-ncbi-nlm-nih-gov-api-6421b0b5/get_article_citations \
  -H "Authorization: Bearer YOUR_LOCUS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"pmcid":"<string>"}'
```

### get_journal_articles

Get articles from a specific journal in PMC. Searches by journal name and returns paginated results sorted by publication date. Supports pagination via offset.

**Estimated cost:** Metered

| Field | Type | Required | Description |
|-------|------|----------|-------------|
| `journal` | string | Yes | Journal name or NLM abbreviation (e.g., 'Nature', 'BMC Public Health') |
| `limit` | integer | No | Number of results to return |
| `offset` | integer | No | Offset for pagination |

```bash
curl -X POST https://api.paywithlocus.com/api/wrapped/parse-pmc-ncbi-nlm-nih-gov-api-6421b0b5/get_journal_articles \
  -H "Authorization: Bearer YOUR_LOCUS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"journal":"<string>","limit":"<integer>","offset":"<integer>"}'
```

### get_similar_articles

Get articles similar to a specific PMC article based on PubMed's related article algorithm. Converts PMC ID to PMID, finds PubMed neighbors, then filters to articles available in PMC. Returns up to 20 similar article summaries.

**Estimated cost:** Metered

| Field | Type | Required | Description |
|-------|------|----------|-------------|
| `pmcid` | string | Yes | PMC ID to find similar articles for (e.g., 'PMC4728819' or '4728819') |

```bash
curl -X POST https://api.paywithlocus.com/api/wrapped/parse-pmc-ncbi-nlm-nih-gov-api-6421b0b5/get_similar_articles \
  -H "Authorization: Bearer YOUR_LOCUS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"pmcid":"<string>"}'
```

### list_journals

Search for journals indexed in NLM catalog that are available through NCBI. Returns journal name, ISSN, and publisher information. Omitting the query returns recently indexed journals.

**Estimated cost:** Metered

| Field | Type | Required | Description |
|-------|------|----------|-------------|
| `query` | string | No | Search keyword for journal title. Omitting returns recently indexed journals. |

```bash
curl -X POST https://api.paywithlocus.com/api/wrapped/parse-pmc-ncbi-nlm-nih-gov-api-6421b0b5/list_journals \
  -H "Authorization: Bearer YOUR_LOCUS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"query":"<string>"}'
```

### search_articles

Full-text search over PubMed Central articles by keyword. Supports PubMed query syntax including Boolean operators and field qualifiers. Returns paginated article summaries with identifiers, titles, authors, journals, and publication dates. Sort by relevance (default) or date.

**Estimated cost:** Metered

| Field | Type | Required | Description |
|-------|------|----------|-------------|
| `limit` | integer | No | Number of results to return (max 100) |
| `offset` | integer | No | Offset for pagination |
| `query` | string | Yes | Search keywords (supports PubMed query syntax including Boolean operators and field qualifiers) |
| `sort` | string | No | Sort order for results |

```bash
curl -X POST https://api.paywithlocus.com/api/wrapped/parse-pmc-ncbi-nlm-nih-gov-api-6421b0b5/search_articles \
  -H "Authorization: Bearer YOUR_LOCUS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"limit":"<integer>","offset":"<integer>","query":"<string>","sort":"<string>"}'
```