Osf API

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.

Authentication

Public read access requires no authentication. For creating or modifying resources, generate a personal access token at https://osf.io/settings/tokens.

# Public access (no auth needed)
curl "https://api.osf.io/v2/nodes/?filter[title]=reproducibility"

# Authenticated access for write operations
export OSF_TOKEN=$OSF_TOKEN
curl -H "Authorization: Bearer $OSF_TOKEN" \
  "https://api.osf.io/v2/users/me/"

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

Query Parameters

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']}")

Common Research Patterns

• Preregistration Review: Search for preregistered studies in your field to understand how others formulate hypotheses, specify sample sizes, and plan analyses before data collection. Essential for meta-science and methodological research.
• Preprint Discovery: Use the preprints endpoint to find the latest unrefereed manuscripts across multiple community servers, getting access to cutting-edge findings before formal publication.
• Open Data Access: Retrieve datasets attached to OSF projects for replication attempts, secondary analyses, or meta-analyses. OSF projects often include raw data, analysis scripts, and materials.
• Collaboration Mapping: Explore contributors and linked projects to understand research collaboration networks in specific domains.
• Reproducibility Audits: Programmatically check whether published studies have associated preregistrations, open data, or open materials on OSF.

Rate Limits and Best Practices

• Rate limit: 100 requests per minute for unauthenticated, higher limits for authenticated requests
• Pagination: Use page and page[size] parameters; default page size is 10
• JSON:API format: Responses follow JSON:API specification; data is under the data key, relationships are linked
• Sparse fieldsets: Use fields[nodes]=title,date_created to request only needed fields
• Embedding: Use embed=contributors to include related resources in a single request
• Respect the service: Add delays between rapid sequential requests; use the links.next URL for pagination

References

• OSF
• OSF API Documentation
• OSF Preprints
• OSF Registrations (Preregistration)
• Center for Open Science