PubMed Search inputs and parameters

You search by a text query — plain-English terms or raw PubMed syntax with field tags. How precisely you scope that query (field tags, Boolean operators, date ranges) is what most affects which publications come back.

Input methods

You run a PubMed search by asking Ivy in chat, in plain English or in PubMed syntax. There is no form, job, or command for it.

Chat input (natural language)

Type a search request in plain English. The orchestrator detects PubMed intent and constructs the appropriate query.

Examples:

Search PubMed for KRAS G12C inhibitors
Find papers on mRNA vaccine delivery published after 2023
Show me reviews about CAR-T cell therapy in solid tumors

The orchestrator handles query construction, field tag insertion, and date formatting automatically. You can also provide raw PubMed syntax if you prefer:

Search PubMed for "BRCA1[Gene] AND breast cancer[MeSH] AND 2024[DP]"

What you can ask for

Plain search

A plain search runs ESearch, then ESummary and EFetch in parallel, so it returns full records — abstract, MeSH terms, and keywords — not just metadata.

Filtered search

When you ask for a filter by author, affiliation, date range, or article type, Ivy runs a filtered search that builds the field-tagged query for you. It only calls ESearch + ESummary — not EFetch — so its results have no abstract, MeSH terms, or keywords. To keep the abstracts, ask for the filter as a field tag inside the query instead (see Field tags).

You cannot filter by journal or MeSH term outside the query, and results cannot be re-sorted — ESearch always sorts by relevance. Put a journal ([TA]) or MeSH ([MH]) tag in the query instead.

Query syntax

Free-text queries

Simple keyword searches match against title, abstract, and MeSH terms:

kinase inhibitor resistance mechanisms

Boolean operators

Combine terms with AND, OR, NOT (must be uppercase):

EGFR AND resistance AND NOT review[PT]

Field tags

Restrict searches to specific fields:

Date ranges

Filter by publication date:

EGFR inhibitors AND 2023/01/01:2024/12/31[DP]

Or ask for a date range in plain words ("published between 2023 and 2024").

Phrase searching

Use double quotes for exact phrases:

"checkpoint inhibitor" AND "non-small cell lung cancer"

Truncation

Use an asterisk for wildcard matching:

immun* AND therap*

This matches "immunotherapy", "immunotherapeutic", "immune therapy", etc.

Input validation

Query validation

• Plain search: minimum 1 character, no enforced maximum
• Filtered search: minimum 2 characters, maximum 500 characters
• Empty queries: Rejected with an error message
• Special characters: PubMed syntax characters ([, ], ", *, AND, OR, NOT) are preserved as search operators

Date validation

• Accepted formats: YYYY, YYYY/MM, YYYY/MM/DD
• Range check: the start date must be before the end date when both are given
• Future dates: Accepted but will return no results
• Invalid formats: Silently ignored (search proceeds without date filter)

Limit validation

• Minimum: 1
• Maximum: 100
• Values outside range: Clamped to nearest boundary
• Non-integer values: Rounded down

Example prompts

Simple keyword search

Search PubMed for CRISPR gene editing in cancer, top 20 papers

Filtered search

Find reviews on kinase inhibitor resistance by Kantarjian H, published 2022-2024, up to 50 results

MeSH-based search

A MeSH field tag in the query keeps this a plain search, so abstracts and MeSH terms come back:

Search PubMed for "Protein Kinases[MH] AND Drug Resistance, Neoplasm[MH]", 30 results

Author and institution search

Find papers on CAR-T cells by June CH at the University of Pennsylvania

Batch processing strategies

PubMed Search does not support true batch queries in a single API call. For multi-term searches:

• Sequential queries: Run separate searches for each term and review results independently
• Boolean combination: Combine related terms in a single query using OR operators
• Workflow chaining: Ask the model to pull terms from a prior result's abstracts and generate follow-up PubMed queries

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