openapi: 3.0.3
info:
  title: NCBI URL BLAST Link API
  description: 'The NCBI BLAST URL API allows developers to submit BLAST (Basic Local Alignment Search Tool) sequence searches for processing at NCBI using HTTPS. The API operates in three phases: (1) PUT request to submit a search and receive a request ID (RID), (2) polling GET requests to check search status, (3) GET request to retrieve results in the desired format. Supports nucleotide (blastn, blastx) and protein (blastp, tblastn, tblastx) searches.'
  version: 1.0.0
  contact:
    name: NCBI BLAST
    url: https://blast.ncbi.nlm.nih.gov/doc/blast-help/developerinfo.html
  license:
    name: Public Domain
    url: https://www.usa.gov/government-works
servers:
- url: https://blast.ncbi.nlm.nih.gov/blast
  description: NCBI BLAST Server
tags:
- name: Link
  description: Find linked records across databases
paths:
  /elink.fcgi:
    get:
      operationId: getLinkages
      summary: Get Linked Records
      description: Find records related to a set of input UIDs in any Entrez database. Supports finding related articles, linked sequences, gene-to-protein links, and other cross-database connections.
      tags:
      - Link
      parameters:
      - name: dbfrom
        in: query
        description: Source database
        required: true
        schema:
          type: string
        example: pubmed
      - name: db
        in: query
        description: Target database (leave empty for related records in same db)
        required: false
        schema:
          type: string
      - name: id
        in: query
        description: Comma-separated source UIDs
        required: true
        schema:
          type: string
        example: '33515491'
      - name: api_key
        in: query
        required: false
        schema:
          type: string
      - name: cmd
        in: query
        description: Link command (neighbor, prlinks, llinks, acheck, ncheck, lcheck)
        required: false
        schema:
          type: string
          default: neighbor
      - name: linkname
        in: query
        description: Named link to follow (e.g. pubmed_pubmed_citedin)
        required: false
        schema:
          type: string
      - name: retmode
        in: query
        required: false
        schema:
          type: string
          default: json
      responses:
        '200':
          description: Linked record UIDs and link names
          content:
            application/json:
              schema:
                type: object