Which API hosts resolve but refuse a connection?

The DNS name still answers and something owns it; what is behind it will not complete a TCP or TLS handshake. This is the failure that looks healthiest from a distance - the domain resolves, the certificate may even be listed - and stops every call.

223 records across 146 subjects, observed 2026-09-10. Every one carries a check you can run in a single request.

io.github.junct-bot24
io.github.mctx-ai11
io.github.varvararatta/legal_mcp11
io.github.Ansarii/mcp-rate-limiter8
io.github.HyosikPark/geocode8
com.brainiall/nlp7
xyz.tenzro/tenzro7
com.fenetresurciel.mcp/skybridge3
ProxyKingdom-Api2
hetras-certification.net2
io.github.OrbisAPI/orbis-marketplace2
io.github.c5huracan2
io.github.lexsocket/mcp-ted2
io.github.srimisra/defillama-mcp2
Bets API1
Checks API1
ETSI GS MEC 010-2 - Part 2: Application lifecycle, rules and requirements management1
Gateway1
Pinecone API1
Snyk API1
Wellknown1
abstractapi.com1
ai.dataparrot/data-parrot1
ai.djwizard/tvwizard1
app.locize.mcp/server1
app.twiceshy/twiceshy1
bbc.co.uk1
bot.loro/loro1
chat.uproar/uproar1
citycontext.com1
clickup201
co.rulebase/rulebase1
coach.prose/prose-coach1
code-scan.com1
com.awardflightdaily/award-flight-daily1
com.beamtrace/mcp1
com.caudexcatena/caudexcatena-mcp1
com.cinderfi/retirement-planning1
com.cnrcode/tillpad1
com.consulatehq/consulate1
com.crabbitmq/mcp1
com.csquaredsystems/mcp-registry-test1
com.cualbet/cualbet-mcp1
com.donotact/donotact1
com.emtailabs/xray-vision1
com.feranor/resilience1
com.forgetreasury/treasury1
com.gettransformseo/mcp1
com.givemeanode/givemeanode1
com.knowledge-raven1
com.kresmion/kresmion1
com.magnificentjobs/jobs1
com.meetdewey/dewey1
com.moltarch/moltarch1
com.olane/cosync-local1
com.ontoramp/transformation-radar1
com.pentest-tools1
com.primerfp.scout/scout1
com.qarera/mcp1
com.regfish/mcp1
com.ritzademo/acme-todo1
com.seespectral/oracle1
com.sematryx/optimizer1
com.sequentum/mcp1
com.sharprod/public-knowledge1
com.telerik/agentic-ui-generator-for-angular1
com.the-snip1
com.timeslope/timeslope-mcp1
com.videtion.hub/agent-hub1
data2crm.com1
dev.agenticemail/mcp1
dev.anotherai/anotherai1
dev.augments/mcp1
dev.brazilmcp/brazilmcp1
dev.datatoll/sicily-stays1
dev.sourced/sourced1
dweet.io1
evetech.net1
gamesparks.net1
getsandbox.com1
i-cue.solutions1
inboxroute.com1
info.agentrank/agentrank1
io.averta/mcp-gateway1
io.docdeploy.www/mcp-server1
io.github.AndreuSerraSastre/fivecoins-validation-plan1
io.github.CacheCarti/dmoera-creator1
io.github.CalBearKen/ls-search1
io.github.Final-Commerce1
io.github.KhizarShabir11
io.github.Larshiensch991
io.github.Lfaykus/flatway-estimate1
io.github.SynapseNetworkAI/synapse-network-mcp-server1
io.github.Vessark/business-days-mcp1
io.github.aataqi-boop1
io.github.abdulrahimiqbal/dreamthreads1
io.github.antonioac11
io.github.carlosge4921
io.github.chaband-ops1
io.github.cmcgrabby-hue1
io.github.davidscoreal/univercity-mcp1
io.github.design-smith1
io.github.dornansgar390-hue1
io.github.gastonrey/licita-app1
io.github.gunning4it1
io.github.halversondm/jolt-transform-web1
io.github.hodlxxi/hodlxxi-readonly1
io.github.igorpdev/databr1
io.github.jfrog/jfrog-mcp-server1
io.github.kc23go1
io.github.kimjin81
io.github.kitxor/checklist-day1
io.github.kultur-dev1
io.github.labrat-01
io.github.mapizarro11
io.github.marksignals/the-ultimate-critic1
io.github.mighty8401
io.github.nadine302324-commits1
io.github.onikora/fix-parser1
io.github.patrickbakowski/agentdilemma1
io.github.pinchwork/pinchwork1
io.github.raphasouthall/neurostack1
io.github.reitsmasieto-wq1
io.github.ronrey/portal1
io.github.ssoward/a2ax1
io.github.sugukurukabe/koko-call1
io.github.svim-labs1
io.github.thegrenadinekid251
io.github.victorgulchenko/mimiq-mcp1
io.sslip.195.82.231.1681
io.teres/booking1
jirafe.com1
koomalooma.com1
lumminary.com1
nrm.se1
openlinksw.com1
pandorabots.com1
phantauth.net1
ru.rewio/mcp1
sheerseo.com1
sv.mcp/el-salvador1
sv.prometheus/mcp1
testfire.net1
xyz.agentzon/agentzon1
xyz.getforward/forward1
xyz.verifiedky/sentinel-4021

All subjects ยท the whole registry, machine-readable

This is not a list of good APIs or bad ones. It is a list of observations, each dated and each disprovable in one request. Absence from it means an operation was not examined, not that it is fine.