Unpaywall is answering right now. Last checked 2 min ago. 205 installs a week from npm. It exposes 45 tools. Last commit 29 Oct 2026.
Unpaywall MCP — open-access lookup for scholarly papers (free, no key)
Every tool that appeared, vanished or quietly changed what it asks for. Recorded since 8 August 2026. No other catalogue keeps this.
Everything else answered, so this is steady rather than shaky. We check every 15 minutes, which is how a one-off gets told apart from the start of a pattern, and how you hear about the next one within the hour instead of from your users.
Endpoint below is the one we actually reach during checks — not the one copied from a README. Last verified 2 min ago.
claude mcp add unpaywall --transport http https://gateway.pipeworx.io/unpaywall/mcp
https://gateway.pipeworx.io/unpaywall/mcp
[mcp_servers.unpaywall]
url = "https://gateway.pipeworx.io/unpaywall/mcp"
{
"mcpServers": {
"unpaywall": {
"url": "https://gateway.pipeworx.io/unpaywall/mcp"
}
}
}
{
"servers": {
"unpaywall": {
"type": "http",
"url": "https://gateway.pipeworx.io/unpaywall/mcp"
}
}
}
Read directly from the server with tools/list, grouped by what they act on.
If a tool disappears, we record the date.
polymarket_arbitrage
polymarket_edge_tracker
polymarket_edges
polymarket_fill_risk
polymarket_kalshi_spread
ask_pipeworx
ask_pipeworx_beta
ask_pipeworx_grounded
archive_compare
archive_evidence
company_facts
company_register_search
pipeworx_feedback
pipeworx_trending
recent_alerts
recent_changes
resolution_audit
resolution_diff
scan_competitor_ai_presence
scan_dependency
updown_divergence_rate
updown_venue_compare
bet_research
classify_row
compare_entities
deep_research
discover_tools
entity_profile
forget
generate_llms_txt
get_oa
kalshi_weather_edge
prediction_calibration
recall
release_calendar_markets
remember
research_row
resolve_entity
subscribe
list_subscriptions
suggest_questions
unsubscribe
validate_claim
ai_visibility_check
search_within
Tools this server used to expose. Anything built against them stopped working on the day they went.
search_papers
| URL | Transport | State | Latency | Checked |
|---|---|---|---|---|
| https://gateway.pipeworx.io/unpaywall/mcp | streamable-http | answering | 152 ms | 2 min ago |
Open access links from Unpaywall. No key required.
Open-access availability for 120M+ scholarly articles via the Unpaywall API
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Scholarly literature search across nine sources
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Answers built from our own checks of this server.