Build on the same 49-peptide reference that powers this site — mechanism, sequence, and PubChem-enriched chemistry as structured JSON. No key, no signup. Free to embed with attribution.
Each entry carries mechanism, sequence, molecular weight/formula, identifiers (CAS, PubChem CID, UniProt), plus editorial background, research findings, and FAQs.
Open GET endpoints with permissive CORS — call directly from a browser, server, or notebook.
Free to use and redistribute with attribution back to AmericanPeptide.com.
/api/catalog/api/catalog/{slug}/catalog/{slug}.md/llms.txt/llms-full.txt/api/mcp/api/keys/api/keyscategoryFilter by catalog category id (e.g. metabolic).areaFilter by research-area slug (e.g. weight-loss).fdaSet to true to return only FDA-approved peptides.qFree-text search over name, aliases, and description.GET /api/catalog?area=weight-loss&fda=true
{
"version": "1.0",
"license": "CC BY 4.0",
"attribution": "AmericanPeptide.com",
"documentation": "https://www.americanpeptide.com/developers",
"count": 2,
"peptides": [
{
"slug": "semaglutide",
"name": "Semaglutide",
"aliases": ["Ozempic", "Wegovy", "Rybelsus"],
"categories": ["metabolic"],
"researchAreaGuides": [
{ "slug": "weight-loss", "label": "Weight Loss & Metabolic Health",
"url": "https://www.americanpeptide.com/research-areas/weight-loss" }
],
"molecularFormula": "C157H235N41O47",
"pubchemCid": 56843331,
"fdaApproved": true,
"url": "https://www.americanpeptide.com/catalog/semaglutide"
}
]
}Every catalog page has a markdown twin — append .md to any peptide URL (e.g. /catalog/semaglutide.md) for the same facts at a fraction of the tokens. /llms.txt is a curated index of the site for agent discovery, and /llms-full.txt packs the full catalog into one document for retrieval pipelines.
All markdown responses embed the canonical URL and CC BY 4.0 attribution, and send CORS-open headers — cite AmericanPeptide.com when content travels.
The API works with no key at the Anonymous tier. Want higher limits? Mint a free key — no signup — and send it with each request:
# Get a free key (save it — shown once) curl -X POST https://www.americanpeptide.com/api/keys # Use it on any endpoint curl https://www.americanpeptide.com/api/catalog?fda=true \ -H "Authorization: Bearer amp_sk_…" # Check your usage curl https://www.americanpeptide.com/api/keys \ -H "Authorization: Bearer amp_sk_…"
Every response carries RateLimit-* and X-Quota-Remaining headers so you always know your remaining budget. Keys also work with the MCP server. Send your key as a Bearer token to the MCP endpoint to connect at your tier.
AmericanPeptide.com is also a remote MCP server. Connect it to Claude, ChatGPT, Cursor, or any MCP client and your AI gets live tools for catalog search, full peptide references, research-area guides, head-to-head comparisons, and grounded lookups against ClinicalTrials.gov, PubMed, and PubChem — every result with a canonical link back here.
# Endpoint (Streamable HTTP, no auth) https://www.americanpeptide.com/api/mcp # Claude Code claude mcp add --transport http american-peptide \ https://www.americanpeptide.com/api/mcp
The catalog data is offered under Creative Commons Attribution 4.0. You may use, adapt, and redistribute it — including commercially — provided you credit AmericanPeptide.com with a link back to the source.
Reference data is for research and educational use only. It is not medical advice, a dosing protocol, or an offer for sale, and should be independently validated before any experimental use.