All skillsImportant: URL-encode colons in HP IDs —
Skillintermediate
HPO (Human Phenotype Ontology)
| Endpoint | Description | |----------|-------------| | `/hpo/search?q={query}&max={n}` | Search HPO terms by name | | `/hpo/term/{id}` | Term details | | `/hpo/term/{id}/genes` | Genes associated with a phenotype | | `/hpo/term/{id}/diseases` | Diseases associated with a phenotype | | `/hpo/term/{id}/children` | Child terms in hierarchy | | `/hpo/term/{id}/parents` | Parent terms | | `/hpo/gene/{
Claude Code Knowledge Pack7/10/2026
Overview
HPO (Human Phenotype Ontology)
Base URL
https://ontology.jax.org/api/hp
Auth
No API key required.
Important: URL-encode colons in HP IDs — HP:0001250 becomes HP%3A0001250
Key Endpoints
| Endpoint | Description |
|---|---|
/hpo/search?q={query}&max={n} | Search HPO terms by name |
/hpo/term/{id} | Term details |
/hpo/term/{id}/genes | Genes associated with a phenotype |
/hpo/term/{id}/diseases | Diseases associated with a phenotype |
/hpo/term/{id}/children | Child terms in hierarchy |
/hpo/term/{id}/parents | Parent terms |
/hpo/gene/{gene_id} | Phenotypes for a gene (Entrez ID) |
/hpo/disease/{disease_id} | Phenotypes for a disease (OMIM/ORPHA) |
Example Calls
# Search for "seizure"
https://ontology.jax.org/api/hp/hpo/search?q=seizure&max=5
# Term details for Seizure
https://ontology.jax.org/api/hp/hpo/term/HP%3A0001250
# Genes associated with Seizure
https://ontology.jax.org/api/hp/hpo/term/HP%3A0001250/genes
# Diseases for Seizure
https://ontology.jax.org/api/hp/hpo/term/HP%3A0001250/diseases
# Phenotypes for SCN1A (Entrez 6323)
https://ontology.jax.org/api/hp/hpo/gene/6323
Response Format
JSON. Terms: id, name, definition, synonyms. Gene associations: genes[] with geneId, geneSymbol. Diseases: diseases[] with diseaseId, diseaseName.
Rate Limits
No published limits. Bulk annotation files at https://hpo.jax.org/data/annotations