# National Center for Biotechnology Information (NCBI)

**Canonical:** https://apis.io/providers/ncbi/  
**Website:** https://www.ncbi.nlm.nih.gov/home/develop/  
**APIs profiled:** 14

The National Center for Biotechnology Information (NCBI) provides a suite of free, publicly accessible REST APIs for querying and retrieving biological and biomedical data. Offerings include the Entrez Programming Utilities (E-utilities) for searching and fetching records across 38 databases including PubMed, GenBank, Gene, and Taxonomy; the BLAST URL API for homology sequence searching; the NCBI Datasets API for downloading genomic, gene, and taxonomy data; and PubChem APIs for chemical compound data. PMC developer tools provide Open Access article retrieval, metadata harvesting, identifier conversion, and citation export.

## Kin Score — 39.0 / 100 (thin)

Scored 2026-08-20 under rubric 0.12.0. Trend: flat (+0.0 from 39.0).

| Facet | Score |
|---|---|
| Discoverability | 81.5 |
| Contract Quality | 59.5 |
| Governance | 9.8 |
| Contract Governance | 9.8 |
| Operational Transparency | 0.0 |
| Developer Ergonomics | 28.6 |
| Commercial Clarity | 39.5 |
| Access Clarity | 39.5 |

Regulatory layer — **Health**: 26.3 (matched via tags).

## Agent readiness — 35.0 (agent-ready)

| Dimension | Value |
|---|---|
| Spec Presence | yes |
| Agentic Access | derived |
| Reversibility Documented | no |
| MCP Server | no |
| Auth Clarity | yes |
| Idempotency | no |
| Error Semantics | no |
| OpenAPI Examples | verified |
| Rate Limit Signal | documented |
| Event Surface Described | no |
| Agent Skills | no |
| Well Known Catalog | no |
| Consent Identity | no |
| Agent Card | no |
| Dry Run Mode | no |

## Access

Free · Open access — onboarding: open, pricing: free, trial: no (confidence: high).

## APIs (14)

- **NCBI Entrez E-utilities API** — The Entrez Programming Utilities (E-utilities) are the public API to the NCBI Entrez system, providing access to over 38 Entrez databases including PubMed, GenBank (Nuccore), Ge...
- **NCBI BLAST URL API** — The BLAST (Basic Local Alignment Search Tool) URL API allows developers to submit nucleotide and protein sequence homology searches via HTTPS, poll for job status, and retrieve ...
- **PubChem PUG REST API** — The PubChem Power User Gateway (PUG) REST API provides programmatic access to PubChem's chemical compound, substance, and bioassay data. Developers can retrieve compound propert...
- **PMC Open Access API (OA Service)** — The PubMed Central Open Access API retrieves citation data, licensing details, and FTP download locations for Open Access articles in the PMC archive. Queries accept a PMC ident...
- **PMC ID Converter API** — The PMC ID Converter API translates between PubMed Central identifiers (PMCID), PubMed identifiers (PMID), Manuscript IDs, and Digital Object Identifiers (DOI). Batch conversion...
- **PMC OAI-PMH Service** — The PMC OAI-PMH (Open Archives Initiative Protocol for Metadata Harvesting) service allows bulk harvesting of metadata for all items in the PMC archive and full-text content for...
- **National Center for Biotechnology Information (NCBI) BioSample API** — #### Options to download BioSample data. This BioSample service allows you to get BioSample data as a data report.
- **National Center for Biotechnology Information (NCBI) Gene API** — #### Options to download gene data, including the associated sequence and metadata. These gene services allow you to get gene metadata as a data report or download gene, transcr...
- **National Center for Biotechnology Information (NCBI) Genome API** — #### Options to download assembled genome data, including the associated sequence, annotation and metadata. These genome services allow you to get genome metadata as a data repo...
- **National Center for Biotechnology Information (NCBI) Organelle API** — #### Options to download RefSeq organelle genome data, including the associated sequence and metadata. These organelle services allow you to get RefSeq organelle genome metadata...
- **National Center for Biotechnology Information (NCBI) Prokaryote API** — #### Options to download prokaryote gene data, including the associated sequence and metadata. These gene services allow you to download gene and protein sequence, and metadata ...
- **National Center for Biotechnology Information (NCBI) Taxonomy API** — #### Options to download taxonomy data. These taxonomy services allow you to get taxonomy data as a data report or download taxonomy data as a taxonomy data package, for taxonom...
- **National Center for Biotechnology Information (NCBI) Version API** — #### Retrieve the current version of all NCBI Datasets services. NCBI Datasets services follow the [Semantic Versioning 2.0.0 Schema](https://semver.org/spec/v2.0.0.html).
- **National Center for Biotechnology Information (NCBI) Virus API** — #### Options to download virus genome data, including the associated sequence and metadata. These virus services allow you to get virus genome metadata as a data report or downl...

## Agentic access (1)

- **Ncbi Agentic Access** — 107 operations · 41 acting

## Security (2)

- **Ncbi Authentication** — apiKey · 2 schemes
- **Ncbi Domain Security** — TLSv1.3 · HSTS · DNSSEC

## Plans (7)

- **Blast**
- **Datasets**
- **E Utilities**
- **Pmc Id Converter**
- **Pmc Oa**
- **Pmc Oai Pmh**
- **Pubchem Pug Rest**

## Tags

Bioinformatics, Genomics, Life Sciences, PubMed, Sequences, BLAST, Taxonomy, Chemistry, Open Access

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/providers/ncbi/). Scores are computed from the provider's own public artifacts under a published rubric.