OSF (Open Science Framework) API

Overview

The Open Science Framework by the Center for Open Science provides infrastructure for the entire research lifecycle — project management, file storage, preprint hosting, and registrations. The API enables search, project creation, file management, and preprint discovery across OSF Preprints, PsyArXiv, SocArXiv, and 25+ community preprint servers. Free, no auth for read access.

API Endpoints

Base URL

https://api.osf.io/v2

Search

# Search across all OSF content
curl "https://api.osf.io/v2/search/?q=replication+crisis&page[size]=20"

# Search preprints
curl "https://api.osf.io/v2/preprints/?filter[q]=machine+learning&page[size]=20"

# Filter by preprint provider
curl "https://api.osf.io/v2/preprints/?filter[provider]=psyarxiv&filter[q]=cognitive+bias"

# Search registrations (pre-registered studies)
curl "https://api.osf.io/v2/registrations/?filter[q]=randomized+controlled+trial"

Projects

# Get public projects
curl "https://api.osf.io/v2/nodes/?filter[public]=true&filter[q]=neuroimaging"

# Get project details
curl "https://api.osf.io/v2/nodes/{node_id}/"

# Get project files
curl "https://api.osf.io/v2/nodes/{node_id}/files/"

# Get project contributors
curl "https://api.osf.io/v2/nodes/{node_id}/contributors/"

Preprint Providers

Provider	Filter	Disciplines
OSF Preprints	osf	Multidisciplinary
PsyArXiv	psyarxiv	Psychology
SocArXiv	socarxiv	Social sciences
EarthArXiv	eartharxiv	Earth sciences
BioHackrXiv	biohackrxiv	Bioinformatics
engrXiv	engrxiv	Engineering
MedArXiv	medarxiv	Medical sciences
NutriXiv	nutrixiv	Nutrition

Query Parameters

Parameter	Description	Example
filter[q]	Text search	filter[q]=open+data
filter[provider]	Preprint server	filter[provider]=psyarxiv
filter[subjects]	Subject filter	Subject taxonomy ID
filter[date_created]	Date filter	filter[date_created][gte]=2024-01-01
page[size]	Results per page (max 100)	page[size]=50
page	Page number	page=2

Response Structure (Preprint)

{
  "data": [
    {
      "id": "abc12",
      "type": "preprints",
      "attributes": {
        "title": "Replication of the Ego Depletion Effect",
        "description": "We attempted to replicate...",
        "date_created": "2024-06-15T10:00:00Z",
        "date_published": "2024-06-16T08:00:00Z",
        "doi": "10.31234/osf.io/abc12",
        "is_published": true,
        "subjects": [["Social and Behavioral Sciences", "Psychology"]],
        "tags": ["replication", "ego depletion"]
      },
      "relationships": {
        "contributors": {"links": {"related": {"href": "..."}}},
        "primary_file": {"links": {"related": {"href": "..."}}}
      }
    }
  ]
}

Python Usage

import requests

BASE_URL = "https://api.osf.io/v2"


def search_preprints(query: str, provider: str = None,
                     page_size: int = 20) -> list:
    """Search OSF preprints across providers."""
    params = {
        "filter[q]": query,
        "page[size]": page_size,
    }
    if provider:
        params["filter[provider]"] = provider

    resp = requests.get(f"{BASE_URL}/preprints/", params=params)
    resp.raise_for_status()
    data = resp.json()

    results = []
    for item in data.get("data", []):
        attrs = item.get("attributes", {})
        results.append({
            "id": item.get("id"),
            "title": attrs.get("title"),
            "description": (attrs.get("description") or "")[:300],
            "doi": attrs.get("doi"),
            "date": attrs.get("date_published", "")[:10],
            "tags": attrs.get("tags", []),
            "url": f"https://osf.io/{item.get('id')}/",
        })
    return results


def search_registrations(query: str,
                         page_size: int = 20) -> list:
    """Search pre-registered studies on OSF."""
    params = {
        "filter[q]": query,
        "page[size]": page_size,
    }
    resp = requests.get(f"{BASE_URL}/registrations/", params=params)
    resp.raise_for_status()
    data = resp.json()

    results = []
    for item in data.get("data", []):
        attrs = item.get("attributes", {})
        results.append({
            "id": item.get("id"),
            "title": attrs.get("title"),
            "description": (attrs.get("description") or "")[:300],
            "date_registered": attrs.get("date_registered", "")[:10],
            "registration_schema": attrs.get("registration_supplement"),
        })
    return results


def get_project_files(node_id: str) -> list:
    """List files in an OSF project."""
    resp = requests.get(f"{BASE_URL}/nodes/{node_id}/files/")
    resp.raise_for_status()
    data = resp.json()

    providers = []
    for item in data.get("data", []):
        attrs = item.get("attributes", {})
        providers.append({
            "provider": attrs.get("provider"),
            "name": attrs.get("name"),
        })
    return providers


# Example: search psychology preprints
preprints = search_preprints("cognitive load", provider="psyarxiv")
for p in preprints[:5]:
    print(f"[{p['date']}] {p['title']}")
    print(f"  DOI: {p['doi']}")

# Example: find pre-registered clinical trials
regs = search_registrations("randomized placebo")
for r in regs[:5]:
    print(f"[{r['date_registered']}] {r['title']}")

Use Cases

1. Preprint discovery: Search across 25+ preprint servers
2. Pre-registration search: Find registered study protocols
3. Open data access: Download shared research datasets
4. Reproducibility: Access materials, data, and code for published studies
5. Project management: Programmatic project and file management

References

• OSF
• OSF API Documentation
• OSF Preprints
• Center for Open Science