pubmed-cli

PubMed from your terminal. Search, fetch, cite, traverse — built for humans and AI agents. Zero dependencies, structured JSON, agent-ready.

Install

brew tap drpedapati/tap
brew install sciclaw-pubmed-cli

Binary: /opt/homebrew/bin/pubmed

Verify: pubmed --help

Configuration

Set your NCBI API key for higher rate limits (recommended):

export NCBI_API_KEY="your-key"

If you're using sciClaw, you can also set this via the sciclaw onboard wizard, or in ~/.picoclaw/config.json:

{
  "tools": {
    "pubmed": { "api_key": "your-key" }
  }
}

• Without key: 3 requests/second
• With key: 10 requests/second
• Get a key at: https://www.ncbi.nlm.nih.gov/account/settings/

Commands

search — Query PubMed

pubmed search "fragile x syndrome" --json --limit 10
pubmed search "autism AND EEG" --json --limit 20 --sort date
pubmed search "ALS" --json --year 2023-2025 --type review
pubmed search "CRISPR" --json --sort cited --limit 5

Returns: count (total hits), ids (PMIDs), query_translation (how NCBI interpreted the query).

Supports: Boolean operators (AND, OR, NOT), MeSH terms ([MeSH Terms]), field tags ([Title/Abstract], [Author]), wildcards (neoplas*), phrase search ("exact phrase").

fetch — Get article details

pubmed fetch 38000001 --json
pubmed fetch 38000001 38000002 38000003 --json
pubmed fetch "38000001,38000002" --json

Returns per article: pmid, title, abstract, abstract_sections (structured), authors (with affiliations), journal, volume, issue, pages, year, doi, pmcid, mesh_terms (with major topic flags), publication_types.

cited-by — Papers that cite this article

pubmed cited-by 38000001 --json --limit 10

Returns: source_id, links (PMIDs of citing papers).

references — Papers cited by this article

pubmed references 38000001 --json --limit 10

Returns: source_id, links (PMIDs of referenced papers).

related — Similar articles with relevance scores

pubmed related 38000001 --json --limit 10

Returns: source_id, links (PMIDs with score — higher = more similar).

mesh — MeSH vocabulary lookup

pubmed mesh "depression" --json
pubmed mesh "autism spectrum disorder" --json

Returns: ui (MeSH ID), name, scope_note, tree_numbers, entry_terms (synonyms), annotation.

Output Formats

| Flag | Format | Use case | |------|--------|----------| | --json | Structured JSON | Agent parsing, programmatic use | | --human / -H | Rich terminal tables | Interactive exploration | | --csv FILE | CSV export | Spreadsheet import, data analysis | | --ris FILE | RIS citations | Zotero, EndNote, Mendeley import |

Always use --json for agent workflows. The other formats are for human review and export.

Search Modifiers

| Flag | Values | Example | |------|--------|---------| | --limit N | Any positive integer (default 20) | --limit 50 | | --sort | relevance, date, cited | --sort cited | | --year | YYYY or YYYY-YYYY | --year 2020-2025 | | --type | review, trial, meta-analysis, randomized, case-report, or custom | --type review |

Workflow: Systematic Literature Search

# 1. Search with filters
pubmed search "ALS AND biomarkers" --json --limit 50 --year 2020-2025 --type review > search.json

# 2. Fetch full details for top results
cat search.json | jq -r '.ids[:10] | join(" ")' | xargs pubmed fetch --json > articles.json

# 3. Check what each key paper cites
pubmed references 38000001 --json --limit 20 > refs.json

# 4. Find related work
pubmed related 38000001 --json --limit 20 > related.json

# 5. Export for reference manager
pubmed fetch 38000001 38000002 38000003 --ris bibliography.ris

Workflow: Citation Network Traversal

# Start with a seed paper
pubmed fetch 38000001 --json

# Forward citations (who cited this?)
pubmed cited-by 38000001 --json --limit 20

# Backward citations (what did this cite?)
pubmed references 38000001 --json --limit 20

# Similar papers (NCBI's relevance algorithm)
pubmed related 38000001 --json --limit 20

# Chain: fetch details of citing papers
pubmed cited-by 38000001 --json | jq -r '.links[].id' | head -5 | xargs pubmed fetch --json

Workflow: MeSH-Guided Search

# 1. Look up the correct MeSH term
pubmed mesh "fragile x" --json

# 2. Use the official MeSH term in search
pubmed search '"Fragile X Syndrome"[MeSH Terms]' --json --limit 20

# 3. Combine with other terms
pubmed search '"Fragile X Syndrome"[MeSH] AND EEG[Title/Abstract]' --json --year 2020-2025

Exit Codes

• 0 — success
• 1 — user error (invalid flags, bad PMID) or API failure

Error messages are written to stderr with actionable descriptions.

Rate Limiting

Built-in rate limiter respects NCBI guidelines:

• 3 req/s without API key, 10 req/s with key
• Automatic retry on HTTP 429 with exponential backoff
• Respects Retry-After headers