Database Lookup

You have access to 78 public databases through their REST APIs. Your job is to figure out which database(s) are relevant to the user's question, query them, and return the raw JSON results along with which databases you used.

Core Workflow

1. Understand the query — What is the user looking for? A compound? A gene? A pathway? A patent? Expression data? An economic indicator? This determines which database(s) to hit.

2. Select database(s) — Use the database selection guide below. When in doubt, search multiple databases — it's better to cast a wide net than to miss relevant data.

3. Read the reference file — Each database has a reference file in references/ with endpoint details, query formats, and example calls. Read the relevant file(s) before making API calls.

4. Make the API call(s) — See the Making API Calls section below for which HTTP fetch tool to use on your platform.

5. Return results — Always return:

   • The raw JSON response from each database
   • A list of databases queried with the specific endpoints used
   • If a query returned no results, say so explicitly rather than omitting it

Database Selection Guide

Match the user's intent to the right database(s). Many queries benefit from hitting multiple databases.

Physics & Astronomy

User is asking about...	Primary database(s)	Also consider
Near-Earth objects, asteroids	NASA (NeoWs)	—
Mars rover images	NASA (Mars Rover Photos)	—
Exoplanets, orbital parameters	NASA Exoplanet Archive	—
Astronomical objects by name/coordinates	SIMBAD	SDSS
Galaxy/star spectra, photometry	SDSS	SIMBAD
Physical constants	NIST	—
Atomic spectra, spectral lines	NIST (ASD)	—

Earth & Environmental Sciences

User is asking about...	Primary database(s)	Also consider
Earthquakes, seismic events	USGS Earthquakes	—
Water data, streamflow, groundwater	USGS Water Services	—
Weather (current, forecast, historical)	OpenWeatherMap	NOAA
Climate data, historical weather stations	NOAA (CDO)	—
Air quality, toxic releases	EPA (Envirofacts)	—

Chemistry & Drugs

User is asking about...	Primary database(s)	Also consider
Chemical compounds, molecules	PubChem	ChEMBL
Molecular properties (weight, formula, SMILES)	PubChem	—
Drug synonyms, CAS numbers	PubChem (synonyms)	DrugBank
Bioactivity data, IC50, binding assays	ChEMBL	BindingDB, PubChem
Drug binding affinities (Ki, IC50, Kd)	ChEMBL, BindingDB	PubChem
Drug-target interactions	ChEMBL, DrugBank	BindingDB, Open Targets
Ligands for a protein target (by UniProt)	BindingDB	ChEMBL
Target identification from compound structure	BindingDB (SMILES similarity)	ChEMBL
Drug labels, adverse events, recalls	FDA (OpenFDA)	DailyMed
Drug labels (structured product labels)	DailyMed	FDA (OpenFDA)
Drug pharmacology, indications	DrugBank	FDA
Chemical cross-referencing	PubChem (xrefs)	ChEMBL
Commercially available compounds for screening	ZINC	PubChem
Similarity/substructure search (purchasable)	ZINC	PubChem, ChEMBL
Drug-like compound libraries, building blocks	ZINC	—
FDA-approved drug structures	ZINC (fda subset)	PubChem, FDA
Compound purchasability, vendor catalogs	ZINC	—

Materials Science & Crystallography

User is asking about...	Primary database(s)	Also consider
Materials by formula or elements	Materials Project	COD
Band gap, electronic structure	Materials Project	—
Crystal structures, CIF files	COD	Materials Project
Elastic/mechanical properties	Materials Project	—
Formation energy, thermodynamics	Materials Project	—
Cell parameters, space groups	COD	Materials Project

Biology & Genomics

User is asking about...	Primary database(s)	Also consider
Biological pathways	Reactome, KEGG	—
What pathways a gene/protein is in	Reactome (mapping), KEGG	—
Enzyme kinetics, catalytic activity	BRENDA	KEGG
Metabolomics studies, metabolite profiles	Metabolomics Workbench	PubChem
m/z or exact mass lookup	Metabolomics Workbench (moverz/exactmass)	PubChem
Protein sequence, function, annotation	UniProt	Ensembl
Protein-protein interactions	STRING	BioGRID
Gene information, genomic location	NCBI Gene	Ensembl
Genome sequences, variants, transcripts	Ensembl	NCBI Gene
Gene expression datasets	GEO (NCBI E-utilities)	—
Gene expression across tissues	GTEx	Human Protein Atlas
Gene expression signatures (CMap/L1000)	LINCS L1000	GEO
Gene set enrichment vs GEO	RummaGEO	GEO
Protein sequences (NCBI)	NCBI Protein	UniProt
Taxonomic classification	NCBI Taxonomy	—
SNP/variant data (dbSNP)	dbSNP	ClinVar, gnomAD
Population variant frequencies	gnomAD	dbSNP
Sequencing run metadata	SRA	ENA, GEO
Nucleotide sequences (European archive)	ENA	SRA, NCBI Gene
Genome assemblies, raw reads (European)	ENA	SRA, Ensembl
Cross-references from sequence accessions	ENA (xref)	NCBI Gene, UniProt
Genome annotations, tracks	UCSC Genome Browser	Ensembl
3D protein structures (experimental)	PDB (RCSB)	EMDB
3D protein structures (predicted)	AlphaFold DB	PDB
EM maps, cryo-EM structures	EMDB	PDB
Protein families, domains	InterPro	UniProt
Chemical entities (biological)	ChEBI	PubChem
Protein/genetic interactions	BioGRID	STRING
Gene function annotations (GO terms)	QuickGO	Gene Ontology
Regulatory elements, ChIP-seq, ATAC-seq	ENCODE	—
TF binding profiles/motifs	JASPAR	ENCODE
Protein expression across tissues	Human Protein Atlas	UniProt
Single-cell atlas projects	Human Cell Atlas	—
Proteomics datasets	PRIDE	—
Mouse gene data	MouseMine	NCBI Gene
Plasmid repository	Addgene	—

Organism/species matters. Most biology databases cover multiple organisms. If the user's query is about a specific organism, pass it explicitly — don't assume human. Common patterns: Ensembl uses {species} in the URL path (e.g. homo_sapiens), STRING/BioGRID/QuickGO use NCBI taxon IDs (species=9606 for human, 10090 for mouse), UniProt uses organism_id:9606 in search queries, KEGG uses organism codes (hsa, mmu). GTEx and Human Protein Atlas are human-only. Check the reference file for each database's specific parameter.

Disease & Clinical

User is asking about...	Primary database(s)	Also consider
Somatic mutations in cancer	COSMIC	Open Targets, cBioPortal
Cancer genomics (TCGA)	GDC (TCGA)	COSMIC, cBioPortal
Cancer study mutations, CNA, expression	cBioPortal	GDC (TCGA), COSMIC
Tumor clinical data (survival, staging)	cBioPortal	GDC (TCGA)
Drug-target-disease associations	Open Targets	ChEMBL
Gene-disease associations	DisGeNET	Open Targets, Monarch
Mendelian disease-gene relationships	OMIM	NCBI Gene
Variant clinical significance	ClinVar (NCBI)	OMIM
GWAS SNP-trait associations	GWAS Catalog	—
Disease-phenotype-gene links	Monarch Initiative	HPO
Phenotype ontology, HPO terms	HPO	Monarch
Pharmacogenomics, drug-gene interactions	ClinPGx (PharmGKB)	DrugBank
Clinical trials for a drug/disease	ClinicalTrials.gov	FDA
Disease-related expression data	GEO	Open Targets

Patents & Regulatory

User is asking about...	Primary database(s)	Also consider
Patents by keyword or technology	USPTO (PatentsView)	—
Patents by inventor or assignee	USPTO (PatentsView)	—
Patent prosecution status	USPTO (PEDS)	—
Trademark lookup	USPTO (TSDR)	—
SEC company filings, 10-K, 10-Q	SEC EDGAR	—

Economics & Finance

User is asking about...	Primary database(s)	Also consider
US economic time series (GDP, CPI, rates)	FRED	BEA
Employment, wages, labor statistics	BLS	FRED
GDP, national accounts	BEA	FRED, World Bank
International development indicators	World Bank	FRED
Interest rates, money supply	Federal Reserve	FRED
Euro exchange rates, ECB monetary stats	ECB	—
US debt, yield curves, fiscal data	US Treasury	FRED
Stock prices, forex, crypto	Alpha Vantage	—
Statistical data across many topics	Data Commons	—

Social Sciences & Demographics

User is asking about...	Primary database(s)	Also consider
US population, housing, income data	US Census	Data Commons
EU statistics (economy, trade, health)	Eurostat	World Bank
Global health indicators (mortality, disease)	WHO GHO	World Bank

Cross-domain queries

User is asking about...	Primary database(s)	Also consider
Everything about a compound	PubChem + ChEMBL + DrugBank	BindingDB, ZINC, Reactome, FDA
Everything about a gene	NCBI Gene + UniProt + Ensembl	Reactome, STRING, COSMIC, cBioPortal, ENA
Everything about a variant	dbSNP + ClinVar + gnomAD	GWAS Catalog, COSMIC, cBioPortal
Drug target pathways	ChEMBL + Reactome	Open Targets, GEO
Prior art for a chemical invention	USPTO + PubChem	ChEMBL
Everything about a material	Materials Project + COD	—
US economic overview	FRED + BLS + BEA	Federal Reserve

When the user's query spans multiple domains (e.g. "what do we know about aspirin" or "find everything about BRCA1"), query all relevant databases in parallel.

Common Identifier Formats

Different databases use different identifier systems. If a query fails, the identifier format may be wrong. Here's a quick reference:

Identifier	Format	Example	Used by
UniProt accession	P##### or Q#####	P04637 (TP53)	UniProt, STRING, AlphaFold, Reactome mapping
Ensembl gene ID	ENSG###########	ENSG00000141510	Ensembl, Open Targets, GTEx
NCBI Gene ID	Integer	7157 (TP53)	NCBI Gene, GEO, DisGeNET, HPO
HGNC ID	HGNC:#####	HGNC:11998	Monarch
PubChem CID	Integer	2244 (aspirin)	PubChem
ZINC ID	ZINC + 15 digits	ZINC000000000053 (aspirin)	ZINC
ENA Project	PRJEB + digits	PRJEB40665	ENA
ENA Run	ERR + digits	ERR1234567	ENA
ENA Experiment	ERX + digits	ERX1234567	ENA
ENA Sample	ERS + digits	ERS1234567	ENA
ChEMBL ID	CHEMBL####	CHEMBL25 (aspirin)	ChEMBL
Reactome stable ID	R-HSA-######	R-HSA-109581	Reactome
HP term	HP:#######	HP:0001250 (seizure)	HPO (URL-encode colon as %3A)
MONDO disease	MONDO:#######	MONDO:0007947	Monarch
GO term	GO:#######	GO:0008150	QuickGO, Gene Ontology
dbSNP rsID	rs########	rs334	dbSNP, GWAS Catalog, gnomAD
GENCODE ID	ENSG###.## (versioned)	ENSG00000139618.17	GTEx (requires version suffix)

Identifier Resolution

When a database doesn't recognize an identifier, convert it using these workflows:

Genes: Symbol (e.g. "TP53") → look up in NCBI Gene (esearch by symbol) → get NCBI Gene ID → convert to Ensembl ID via Ensembl /xrefs/symbol/homo_sapiens/{symbol}, or to UniProt accession via UniProt search (gene_exact:{symbol} AND organism_id:9606).

Compounds: Name → PubChem /compound/name/{name}/cids/JSON → get CID → convert to ChEMBL ID via UniChem or ChEMBL molecule search. If name lookup fails, try SMILES, InChIKey, or CAS number.

Variants: rsID (e.g. "rs334") works directly in dbSNP, ClinVar, GWAS Catalog, gnomAD. For genomic coordinates, use Ensembl VEP to get consequence annotations and linked rsIDs.

Diseases: Name → Open Targets or Monarch search → get EFO or MONDO ID → use in downstream queries.

POST-Only APIs

These databases require HTTP POST and will not work with WebFetch (GET-only). Use curl via your platform's shell tool instead:

Database	Why POST needed	Example
Open Targets	GraphQL endpoint	curl -X POST -H "Content-Type: application/json" -d '{"query":"..."}' https://api.platform.opentargets.org/api/v4/graphql
gnomAD	GraphQL endpoint	curl -X POST -H "Content-Type: application/json" -d '{"query":"..."}' https://gnomad.broadinstitute.org/api
RummaGEO	POST-only enrichment	curl -X POST -H "Content-Type: application/json" -d '{"genes":["..."]}' https://rummageo.com/api/enrich
GDC/TCGA	Complex filter queries	curl -X POST -H "Content-Type: application/json" -d '{"filters":...}' https://api.gdc.cancer.gov/ssms
SEC EDGAR	Requires User-Agent header	curl -H "User-Agent: YourApp [email protected]" https://efts.sec.gov/LATEST/search-index?q=...

API Keys and Access Restrictions

Some databases require API keys or have access restrictions. When an API key is needed:

1. Check the current environment first — the key may already be exported as a shell environment variable (e.g. $FRED_API_KEY). Read it directly from the environment.
2. Fall back to .env — if the variable isn't in the environment, check the .env file in the current working directory.
3. If neither has it — proceed without the key (most APIs still work at lower rate limits) and tell the user which key is missing and how to get one.

Databases requiring API keys (free registration)

Database	Env Variable	Registration URL
FRED	FRED_API_KEY	https://fred.stlouisfed.org/docs/api/api_key.html
BEA	BEA_API_KEY	https://apps.bea.gov/API/signup/
BLS	BLS_API_KEY	https://data.bls.gov/registrationEngine/
NCBI (GEO, Gene)	NCBI_API_KEY	https://www.ncbi.nlm.nih.gov/account/settings/
OpenFDA	OPENFDA_API_KEY	https://open.fda.gov/apis/authentication/
USPTO (PatentsView)	PATENTSVIEW_API_KEY	https://patentsview.org/apis/keyrequest
Data Commons	DATACOMMONS_API_KEY	Google Cloud Console
Materials Project	MP_API_KEY	https://materialsproject.org (free account)
NASA	NASA_API_KEY	https://api.nasa.gov (free, DEMO_KEY available)
NOAA (CDO)	NOAA_API_KEY	https://www.ncdc.noaa.gov/cdo-web/token
OpenWeatherMap	OPENWEATHERMAP_API_KEY	https://openweathermap.org/appid
OMIM	OMIM_API_KEY	https://omim.org/api (free academic)
BioGRID	BIOGRID_API_KEY	https://webservice.thebiogrid.org (free)
Alpha Vantage	ALPHAVANTAGE_API_KEY	https://www.alphavantage.co/support/#api-key
US Census	CENSUS_API_KEY	https://api.census.gov/data/key_signup.html
DisGeNET	DISGENET_API_KEY	https://www.disgenet.org (free academic)
Addgene	ADDGENE_API_KEY	https://www.addgene.org (free account)
LINCS L1000 (CLUE)	CLUE_API_KEY	https://clue.io (free academic)

These are all free to obtain. The APIs work without keys but have lower rate limits. Always try with a key first — if the env variable isn't set, proceed without the key and note in your response that rate limits may be lower.

Databases with paid or restricted access

Database	Restriction	Free alternative
DrugBank	Paid API license required	Use ChEMBL + PubChem + OpenFDA instead
COSMIC	Free academic registration required (JWT auth)	Use Open Targets for cancer mutation data
BRENDA	Free registration required (SOAP, not REST)	Use KEGG for enzyme/pathway data

When a database requires paid access or registration the user hasn't set up:

1. Fall back to a free alternative that can answer the same question
2. Tell the user which database you couldn't access, why, and what you used instead
3. If the user specifically requests a restricted database, explain the access requirements so they can set it up

Loading API keys

Step 1 — Check the current environment. The key may already be exported as a shell variable. For example, in Claude Code you can check with Bash: echo $FRED_API_KEY. If the variable is set and non-empty, use it.

Step 2 — Check .env file. If the environment variable isn't set, read .env from the current working directory. Format:

FRED_API_KEY=your_key_here
BEA_API_KEY=your_key_here

Step 3 — Proceed without. If neither source has the key, proceed without it (most APIs still work at lower rate limits) and mention this to the user.

Making API Calls

Use your environment's HTTP fetch tool to call REST endpoints. The tool name varies by platform:

Platform	HTTP Fetch Tool	Fallback
Claude Code	WebFetch	curl via Bash
Gemini CLI	web_fetch	curl via shell
Windsurf	read_url_content	curl via terminal
Cursor	No dedicated fetch tool	curl via run_terminal_cmd
Codex CLI	No dedicated fetch tool	curl via shell
Cline	No dedicated fetch tool	curl via execute_command

If you don't recognize your platform or the fetch tool fails, fall back to curl via whatever shell/terminal tool is available. Example:

curl -s -H "Accept: application/json" "https://api.example.com/endpoint"

Request guidelines

• Set Accept: application/json header where supported
• URL-encode special characters in query parameters — SMILES strings (/, #, =, @), compound names with parentheses, and ontology terms with colons (HP:0001250 → HP%3A0001250) are common sources of failures. With curl, use --data-urlencode for safety.
• Parallel OK: When querying different databases (e.g., PubChem + ChEMBL + Reactome), run them in parallel — most APIs have generous rate limits.
• Serialize requests to rate-limited APIs: NCBI APIs (Gene, GEO, Protein, Taxonomy, dbSNP, SRA) at 3 req/sec without key, 10 with key. Also watch: Ensembl (15 req/sec), BLS v1 (25 req/day without key), SEC EDGAR (10 req/sec), NOAA (5 req/sec with token).
• If you get a rate-limit error (HTTP 429 or 503), wait briefly and retry once

Error recovery

If an API returns an error or empty results:

1. Check the identifier format — use the Common Identifier Formats table above. A gene symbol may need to be converted to NCBI Gene ID or Ensembl ID first.
2. Try alternative identifiers — if a compound name fails in PubChem, try SMILES, InChIKey, or CID. If a gene symbol fails, try the NCBI Gene ID.
3. Try a different database — if one database is down or returns nothing, check the "Also consider" column in the selection guide for alternatives.
4. Report the failure — tell the user which database failed, the error, and what you tried instead.

Pagination

Many APIs return paginated results — if you only read the first page, you may miss data. Common patterns:

• Offset/Limit: offset=0&limit=100 → increment offset by limit for the next page (ChEMBL, FRED, NOAA, USGS, NCBI E-utilities, ENA, GDC, FDA)
• Cursor-based: Response includes a nextPageToken or cursor value — pass it in the next request (ClinicalTrials.gov, UniProt)
• Page number: page=1&per_page=50 → increment page (World Bank, cBioPortal, ZINC)

Check the reference file for each database's specific pagination parameters. If a response includes total, totalCount, or next and the number of returned results is less than the total, there are more pages.

For targeted lookups (single gene, single compound), the first page is usually sufficient. Paginate when the user needs comprehensive results (e.g., "all clinical trials for X" or "all known variants in gene Y").

Output Format

Structure your response like this:

## Databases Queried
- **PubChem** — /compound/name/aspirin/property/...
- **Reactome** — /search/query?query=aspirin

## Results

### PubChem
[raw JSON response]

### Reactome
[raw JSON response]

If results are very large, present the most relevant portion and note that additional data is available. But default to showing the full raw JSON — the user asked for it.

Adding New Databases

This skill is designed to grow. Each database is a self-contained reference file in references/. To add a new database:

1. Create references/<database-name>.md following the same format as existing files
2. Add an entry to the database selection guide above
3. The reference file should include: base URL, key endpoints, query parameter formats, example calls, rate limits, and response structure

Available Databases

Read the relevant reference file before making any API call.

Physics & Astronomy

Database	Reference File	What it covers
NASA	references/nasa.md	NEO asteroids, Mars rover, APOD
NASA Exoplanet Archive	references/nasa-exoplanet-archive.md	Exoplanets, orbital parameters
NIST	references/nist.md	Physical constants, atomic spectra
SDSS	references/sdss.md	Galaxy/star spectra, photometry
SIMBAD	references/simbad.md	Astronomical object catalog

Earth & Environmental Sciences

Database	Reference File	What it covers
USGS	references/usgs.md	Earthquakes, water data
NOAA	references/noaa.md	Climate, weather station data
EPA	references/epa.md	Air quality, toxic releases
OpenWeatherMap	references/openweathermap.md	Weather current/forecast

Chemistry & Drugs

Database	Reference File	What it covers
PubChem	references/pubchem.md	Compounds, properties, synonyms
ChEMBL	references/chembl.md	Bioactivity, drug discovery
DrugBank	references/drugbank.md	Drug data, interactions (paid)
FDA (OpenFDA)	references/fda.md	Drug labels, adverse events, recalls
DailyMed	references/dailymed.md	Drug labels (NIH/NLM)
KEGG	references/kegg.md	Pathways, genes, compounds
ChEBI	references/chebi.md	Chemical entities of biological interest
ZINC	references/zinc.md	Commercially available compounds, virtual screening
BindingDB	references/bindingdb.md	Experimentally measured binding affinities

Materials Science

Database	Reference File	What it covers
Materials Project	references/materials-project.md	Band gaps, elastic properties, crystal structures
COD	references/cod.md	Crystal structures, CIF files

Biology & Genomics

Database	Reference File	What it covers
Reactome	references/reactome.md	Biological pathways, reactions
BRENDA	references/brenda.md	Enzyme kinetics, catalysis (SOAP)
UniProt	references/uniprot.md	Protein sequences, function
STRING	references/string.md	Protein-protein interactions
Ensembl	references/ensembl.md	Genomes, variants, sequences
NCBI Gene	references/ncbi-gene.md	Gene information, links
NCBI Protein	references/ncbi-protein.md	Protein sequences, records
NCBI Taxonomy	references/ncbi-taxonomy.md	Taxonomic classification
GEO (NCBI)	references/geo.md	Gene expression datasets
GTEx	references/gtex.md	Gene expression across tissues
PDB	references/pdb.md	Protein 3D structures
AlphaFold DB	references/alphafold.md	Predicted protein structures
EMDB	references/emdb.md	Electron microscopy maps
InterPro	references/interpro.md	Protein families, domains
BioGRID	references/biogrid.md	Protein/genetic interactions
Gene Ontology	references/gene-ontology.md	GO terms, gene annotations
QuickGO	references/quickgo.md	GO annotations (EBI, recommended)
dbSNP	references/dbsnp.md	SNP/variant data
SRA	references/sra.md	Sequencing run metadata
gnomAD	references/gnomad.md	Population variant frequencies (POST)
UCSC Genome Browser	references/ucsc-genome.md	Genome annotations, tracks
ENCODE	references/encode.md	DNA elements, ChIP-seq, ATAC-seq
JASPAR	references/jaspar.md	TF binding profiles/motifs
Human Protein Atlas	references/human-protein-atlas.md	Protein expression across tissues
Human Cell Atlas	references/hca.md	Single-cell atlas data
LINCS L1000	references/lincs-l1000.md	Gene expression signatures (CMap)
RummaGEO	references/rummageo.md	GEO gene set enrichment (POST)
PRIDE	references/pride.md	Proteomics data repository
Metabolomics Workbench	references/metabolomics-workbench.md	Metabolomics studies, metabolites
MouseMine	references/mousemine.md	Mouse genome informatics
ENA	references/ena.md	Nucleotide sequences, reads, assemblies, taxonomy (EMBL-EBI)
Addgene	references/addgene.md	Plasmid repository

Disease & Clinical

Database	Reference File	What it covers
Open Targets	references/opentargets.md	Target-disease associations (POST)
COSMIC	references/cosmic.md	Somatic mutations in cancer
ClinPGx (PharmGKB)	references/clinpgx.md	Pharmacogenomics
ClinicalTrials.gov	references/clinicaltrials.md	Clinical trial registry
OMIM	references/omim.md	Mendelian disease-gene data
ClinVar	references/clinvar.md	Variant clinical significance
GDC (TCGA)	references/tcga-gdc.md	Cancer genomics, mutations (POST)
cBioPortal	references/cbioportal.md	Cancer study mutations, CNA, expression, clinical data
DisGeNET	references/disgenet.md	Gene-disease associations
GWAS Catalog	references/gwas-catalog.md	GWAS SNP-trait associations
Monarch Initiative	references/monarch.md	Disease-phenotype-gene links
HPO	references/hpo.md	Human Phenotype Ontology

Patents & Regulatory

Database	Reference File	What it covers
USPTO	references/uspto.md	Patents, trademarks
SEC EDGAR	references/sec-edgar.md	Company filings (needs User-Agent header)

Economics & Finance

Database	Reference File	What it covers
FRED	references/fred.md	US economic time series
Federal Reserve	references/federal-reserve.md	Monetary/financial data
BEA	references/bea.md	GDP, national accounts
BLS	references/bls.md	Employment, wages, CPI
World Bank	references/worldbank.md	Development indicators
ECB	references/ecb.md	Euro exchange rates, monetary stats
US Treasury	references/treasury.md	Debt, yield curves, fiscal data
Alpha Vantage	references/alphavantage.md	Stocks, forex, crypto
Data Commons	references/datacommons.md	Statistical knowledge graph

Social Sciences & Demographics

Database	Reference File	What it covers
US Census	references/census.md	Population, housing, economic surveys
Eurostat	references/eurostat.md	EU statistics
WHO GHO	references/who.md	Global health indicators