# Ntrs — Wrapped API

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>
> 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 and retrieve NASA technical reports, preprints, and conference papers to find scientific publications across NASA's research archives. Get detailed citation information and discovery capabilities across decades of NASA's technical documentation and scientific findings.

**Category:** Government & Public Data | **Website:** [ntrs.nasa.gov/search](https://ntrs.nasa.gov/search) | **Docs:** [parse.bot/marketplace/f4374557-eb8a-4904-8025-61c1106fe5eb/ntrs-nasa-gov-api](https://parse.bot/marketplace/f4374557-eb8a-4904-8025-61c1106fe5eb/ntrs-nasa-gov-api)

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

## Access

**Base URL:** `https://api.beta.paywithlocus.com/api/wrapped/credits/ntrs/`
**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 citation

Point-lookup for a single NASA technical report by its numeric submission ID. Returns the complete metadata record: title, abstract, full author list with affiliations, publications, meetings, funding numbers, subject categories, and download availability. Use citation IDs obtained from search_citations results.

**Estimated cost:** Metered

| Field | Type | Required | Description |
|-------|------|----------|-------------|
| `citation_id` | string | Yes | The numeric submission ID of the citation (e.g., '20140013470'). |

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

### Search citations

Full-text search over NASA technical reports. `query` matches title, abstract, and keywords; results can be narrowed by NASA center code and publication year range. Returns paginated results. Each Citation carries enough metadata for triage (title, abstract snippet, authors, STI type, center); use get_citation for full detail including meetings, funding, and download status.

**Estimated cost:** Metered

| Field | Type | Required | Description |
|-------|------|----------|-------------|
| `center` | string | No | Filter by NASA center code (e.g., 'JPL', 'GSFC', 'KSC', 'ARC', 'LaRC'). Empty string means no filter. |
| `page` | integer | No | Page number (1-based). |
| `page_size` | integer | No | Results per page, between 1 and 100. |
| `query` | string | No | Search query text (e.g., 'mars rover', 'climate change'). Empty string returns all results. |
| `year_end` | string | No | Filter by end year in YYYY format (e.g., '2024'). Empty string means no upper bound. |
| `year_start` | string | No | Filter by start year in YYYY format (e.g., '2020'). Empty string means no lower bound. |

```bash
curl -X POST https://api.beta.paywithlocus.com/api/wrapped/credits/ntrs/search-citations \
  -H "Authorization: Bearer $LOCUS_CREDITS_SECRET_KEY" \
  -H "Idempotency-Key: $(uuidgen)" \
  -H "Content-Type: application/json" \
  -d '{"center":"<string>","page":"<integer>","page_size":"<integer>","query":"<string>","year_end":"<string>","year_start":"<string>"}'
```

## Next steps

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