[
  {
    "uri": "acme-challenge",
    "description": "Used by the ACME protocol for HTTP-01 domain validation challenges when issuing TLS certificates.",
    "reference": "RFC 8555, Section 8.3",
    "status": "permanent"
  },
  {
    "uri": "agent-card.json",
    "description": "Publishes an Agent Card describing an AI agent's capabilities and endpoints per the Agent2Agent (A2A) protocol.",
    "reference": "A2A Protocol Specification",
    "status": "permanent"
  },
  {
    "uri": "amphtml",
    "description": "Used by the Google AMP cache to signal cache update requests for AMP HTML pages.",
    "reference": "Google AMP Cache Update Specification",
    "status": "provisional"
  },
  {
    "uri": "api-catalog",
    "description": "Provides a machine-readable catalog of APIs available on the host, per the API Catalog RFC.",
    "reference": "RFC 9727",
    "status": "permanent"
  },
  {
    "uri": "appspecific",
    "description": "A namespace for application-specific well-known resources, using reverse-domain-name sub-paths.",
    "reference": "GitHub well-known-uri-appspecific specification",
    "status": "provisional"
  },
  {
    "uri": "ashrae",
    "description": "Used for BACnet device discovery and configuration per ASHRAE building automation standards.",
    "reference": "BACnet Addenda Add-135-2012am",
    "status": "permanent"
  },
  {
    "uri": "assetlinks.json",
    "description": "Declares digital asset links that associate a web origin with native apps for Android App Links verification.",
    "reference": "Google Digital Asset Links Specification",
    "status": "permanent"
  },
  {
    "uri": "bluejetty",
    "description": "Provisional registration by PopUp Space Systems LLC for its BlueJetty service metadata; see the referenced specification for details.",
    "reference": "BlueJetty Well-Known URI Specification",
    "status": "provisional"
  },
  {
    "uri": "broadband-labels",
    "description": "Provides standardized broadband consumer labels with speed, pricing, and service details as mandated by regulators.",
    "reference": "BITAG Broadband Labels Specification",
    "status": "provisional"
  },
  {
    "uri": "brski",
    "description": "Supports Bootstrapping Remote Secure Key Infrastructures (BRSKI) for zero-touch device onboarding.",
    "reference": "RFC 8995",
    "status": "permanent"
  },
  {
    "uri": "caldav",
    "description": "Advertises the CalDAV calendar access service endpoint for clients discovering calendar servers.",
    "reference": "RFC 6764",
    "status": "permanent"
  },
  {
    "uri": "carddav",
    "description": "Advertises the CardDAV address book access service endpoint for clients discovering contact servers.",
    "reference": "RFC 6764",
    "status": "permanent"
  },
  {
    "uri": "change-password",
    "description": "A URL that clients (e.g., password managers) can use to direct users to the site's change-password page.",
    "reference": "W3C Well-Known URL for Changing Passwords",
    "status": "provisional"
  },
  {
    "uri": "cmp",
    "description": "Provides a Certificate Management Protocol (CMP) server endpoint for PKI certificate management.",
    "reference": "RFC 9811, RFC 9482",
    "status": "permanent"
  },
  {
    "uri": "coap",
    "description": "Provides a CoAP-over-TCP or CoAP-over-TLS resource discovery endpoint.",
    "reference": "RFC 8323",
    "status": "permanent"
  },
  {
    "uri": "coap-eap",
    "description": "Provides an EAP-over-CoAP authentication endpoint for network access authentication.",
    "reference": "RFC 9820",
    "status": "permanent"
  },
  {
    "uri": "core",
    "description": "CoRE (Constrained RESTful Environments) link format resource directory for IoT device resource discovery.",
    "reference": "RFC 6690",
    "status": "permanent"
  },
  {
    "uri": "csaf",
    "description": "Provides the root endpoint for accessing Common Security Advisory Framework (CSAF) documents.",
    "reference": "OASIS CSAF v2.0 Standard",
    "status": "provisional"
  },
  {
    "uri": "csaf-aggregator",
    "description": "Provides an aggregator listing of CSAF trusted providers per the OASIS CSAF standard.",
    "reference": "OASIS CSAF v2.0 Standard",
    "status": "provisional"
  },
  {
    "uri": "csipaus",
    "description": "Discovery location for Common Smart Inverter Profile - Australia (CSIP-AUS) services used by distributed energy resources.",
    "reference": "SA TS 5573:2025 Common Smart Inverter Profile - Australia",
    "status": "provisional"
  },
  {
    "uri": "csvm",
    "description": "Used for W3C CSV on the Web metadata discovery, linking CSV files to their JSON-LD metadata descriptors.",
    "reference": "W3C Tabular Data Model",
    "status": "permanent"
  },
  {
    "uri": "cyclic-trigger",
    "description": "Parameterless endpoint that external infrastructure calls periodically to reactivate a service instead of it running its own background workers.",
    "reference": "SmartStandards cyclic-trigger Specification",
    "status": "provisional"
  },
  {
    "uri": "did-configuration.json",
    "description": "Links a domain to Decentralized Identifiers (DIDs) for establishing domain linkage credentials.",
    "reference": "Identity Foundation Well Known DID Configuration",
    "status": "provisional"
  },
  {
    "uri": "did.json",
    "description": "Hosts a DID document for the did:web DID method, associating a domain with a decentralized identifier.",
    "reference": "W3C DID Method Web (did:web)",
    "status": "provisional"
  },
  {
    "uri": "dnt",
    "description": "Returns the site's Do Not Track (DNT) tracking status resource in response to user tracking preferences.",
    "reference": "W3C Tracking Preference Expression (DNT)",
    "status": "permanent"
  },
  {
    "uri": "dnt-policy.txt",
    "description": "A machine-readable policy document that declares the site's compliance with the EFF Do Not Track policy.",
    "reference": "EFF DNT Policy",
    "status": "permanent"
  },
  {
    "uri": "dots",
    "description": "Provides a DDoS Open Threat Signaling (DOTS) server endpoint for requesting mitigation of DDoS attacks.",
    "reference": "RFC 9132",
    "status": "permanent"
  },
  {
    "uri": "easy-proxy",
    "description": "Used for proxy configuration discovery in the ByteDance G3 reverse proxy framework.",
    "reference": "ByteDance G3 Project Specification",
    "status": "provisional"
  },
  {
    "uri": "ecips",
    "description": "Hosts an Ethereum Chain Improvement Proposal URI (ECIPURI) descriptor for blockchain chain identification.",
    "reference": "ECIPS 24 Specification",
    "status": "provisional"
  },
  {
    "uri": "edhoc",
    "description": "Provides an Ephemeral Diffie-Hellman Over COSE (EDHOC) key exchange endpoint for constrained devices.",
    "reference": "RFC 9528",
    "status": "permanent"
  },
  {
    "uri": "enterprise-network-security",
    "description": "Hosts enterprise network security policy metadata per ETSI Middlebox Security Protocol specifications.",
    "reference": "ETSI TS 103 523-5",
    "status": "permanent"
  },
  {
    "uri": "enterprise-transport-security",
    "description": "Hosts enterprise TLS/transport security policy metadata per ETSI Middlebox Security Protocol specifications.",
    "reference": "ETSI TS 103 523-3",
    "status": "permanent"
  },
  {
    "uri": "est",
    "description": "Provides an Enrollment over Secure Transport (EST) endpoint for certificate enrollment in PKI systems.",
    "reference": "RFC 7030, RFC 9148",
    "status": "permanent"
  },
  {
    "uri": "funding-manifest-urls",
    "description": "Lists URLs to funding manifest files (funding.json) that describe how to financially support the project.",
    "reference": "Funding JSON Standard",
    "status": "provisional"
  },
  {
    "uri": "genid",
    "description": "A namespace used internally by RDF processors to mint blank node identifiers; not for direct HTTP use.",
    "reference": "RDF 1.1 Concepts and Abstract Syntax",
    "status": "permanent"
  },
  {
    "uri": "gnap-as-rs",
    "description": "Provides discovery metadata for a GNAP Authorization Server acting as a Resource Server.",
    "reference": "RFC 9767, Section 3.1",
    "status": "permanent"
  },
  {
    "uri": "gpc.json",
    "description": "Declares a site's support for and compliance with the W3C Global Privacy Control (GPC) specification.",
    "reference": "W3C Global Privacy Control",
    "status": "provisional"
  },
  {
    "uri": "gs1resolver",
    "description": "Provides a GS1 Digital Link resolver for identifying and resolving GS1 product identifiers (GTINs, etc.).",
    "reference": "GS1 Digital Link Standard",
    "status": "permanent"
  },
  {
    "uri": "hoba",
    "description": "Provides HTTP Origin-Bound Authentication (HOBA) key registration and login endpoints.",
    "reference": "RFC 7486, Section 6",
    "status": "permanent"
  },
  {
    "uri": "host-meta",
    "description": "Provides host-level metadata in XRD format describing services and properties of the host.",
    "reference": "RFC 6415",
    "status": "permanent"
  },
  {
    "uri": "host-meta.json",
    "description": "Provides host-level metadata in JRD (JSON) format describing services and properties of the host.",
    "reference": "RFC 6415",
    "status": "permanent"
  },
  {
    "uri": "hosting-provider",
    "description": "Declares the web hosting provider for a domain to assist in provider identification.",
    "reference": "Automattic Hosting Provider Specification",
    "status": "provisional"
  },
  {
    "uri": "http-opportunistic",
    "description": "Was used for HTTP Opportunistic Security origin policy negotiation; now obsolete and historic.",
    "reference": "RFC 8164, Section 2.3",
    "status": "obsoleted"
  },
  {
    "uri": "ic-domains",
    "description": "Used by the Internet Computer (ICP) blockchain to associate domains with canister smart contracts.",
    "reference": "Internet Computer Documentation",
    "status": "provisional"
  },
  {
    "uri": "idp-proxy",
    "description": "Provides the WebRTC Identity Provider proxy endpoint for peer authentication in WebRTC sessions.",
    "reference": "RFC 8827",
    "status": "permanent"
  },
  {
    "uri": "jmap",
    "description": "Provides JMAP (JSON Meta Application Protocol) server capabilities and endpoint discovery information.",
    "reference": "RFC 8620, Section 2.2",
    "status": "permanent"
  },
  {
    "uri": "keybase.txt",
    "description": "A Keybase identity proof file linking the domain owner to their Keybase cryptographic identity.",
    "reference": "Keybase Well-Known Documentation",
    "status": "permanent"
  },
  {
    "uri": "knx",
    "description": "Provides KNX IoT device and service discovery information for KNX Cloud smart building integration.",
    "reference": "KNX Cloud Specification",
    "status": "provisional"
  },
  {
    "uri": "looking-glass",
    "description": "Provides a Looking Glass service endpoint for querying BGP routing data and network diagnostics.",
    "reference": "RFC 8522, Section 2",
    "status": "permanent"
  },
  {
    "uri": "masque",
    "description": "Provides MASQUE (Multiplexed Application Substrate over QUIC Encryption) proxy service discovery.",
    "reference": "RFC 9298, RFC 9484",
    "status": "permanent"
  },
  {
    "uri": "matrix",
    "description": "Provides Matrix protocol server discovery for both client-server and server-server federation endpoints.",
    "reference": "Matrix Specification",
    "status": "permanent"
  },
  {
    "uri": "mercure",
    "description": "Provides the Mercure Hub endpoint URL for server-sent events and real-time push subscriptions.",
    "reference": "Mercure Protocol Specification",
    "status": "provisional"
  },
  {
    "uri": "mta-sts.txt",
    "description": "Publishes an MTA-STS policy file specifying that email to this domain must be sent over TLS.",
    "reference": "RFC 8461",
    "status": "permanent"
  },
  {
    "uri": "mud",
    "description": "Was used for Manufacturer Usage Description (MUD) file discovery for IoT devices; now obsoleted.",
    "reference": "Obsoleted",
    "status": "obsoleted"
  },
  {
    "uri": "nfv-oauth-server-configuration",
    "description": "Provides OAuth 2.0 authorization server metadata for ETSI NFV (Network Functions Virtualisation) environments.",
    "reference": "ETSI GS NFV-SEC 022",
    "status": "permanent"
  },
  {
    "uri": "ni",
    "description": "Used for Named Information (ni) URI scheme resource access, providing hash-based content identifiers.",
    "reference": "RFC 6920",
    "status": "permanent"
  },
  {
    "uri": "nodeinfo",
    "description": "Provides NodeInfo metadata for federated social networks (e.g., Mastodon, Diaspora) including software info.",
    "reference": "NodeInfo Specification",
    "status": "provisional"
  },
  {
    "uri": "nostr.json",
    "description": "Maps Nostr internet identifier handles (NIP-05) to public keys for user discovery in the Nostr protocol.",
    "reference": "Nostr NIP-05 Specification",
    "status": "provisional"
  },
  {
    "uri": "oauth-authorization-server",
    "description": "Provides OAuth 2.0 Authorization Server metadata including supported grant types and endpoint URLs.",
    "reference": "RFC 8414, Section 3",
    "status": "permanent"
  },
  {
    "uri": "oauth-protected-resource",
    "description": "Provides OAuth 2.0 Protected Resource metadata describing the resource server's authorization requirements.",
    "reference": "RFC 9728, Section 3",
    "status": "permanent"
  },
  {
    "uri": "ohttp-gateway",
    "description": "Provides Oblivious HTTP (OHTTP) gateway key configuration for privacy-preserving HTTP proxying.",
    "reference": "RFC 9540",
    "status": "permanent"
  },
  {
    "uri": "ojobpub.json",
    "description": "Publishes an open job listing manifest for employer job postings in a standardized machine-readable format.",
    "reference": "letsemploy.org Documentation",
    "status": "provisional"
  },
  {
    "uri": "open-resource-discovery",
    "description": "Provides SAP Open Resource Discovery metadata for machine-readable API and service catalog discovery.",
    "reference": "SAP Open Resource Discovery Specification",
    "status": "provisional"
  },
  {
    "uri": "openbindings",
    "description": "Provides OpenBindings service discovery metadata for linking domains to decentralized identifiers and services.",
    "reference": "OpenBindings Specification",
    "status": "provisional"
  },
  {
    "uri": "openid-configuration",
    "description": "Provides OpenID Connect discovery metadata including issuer, endpoint URLs, and supported capabilities.",
    "reference": "OpenID Connect Discovery 1.0",
    "status": "permanent"
  },
  {
    "uri": "openid-federation",
    "description": "Provides an OpenID Federation 1.0 Entity Statement for federated identity trust chain establishment.",
    "reference": "OpenID Federation 1.0, Section 9",
    "status": "provisional"
  },
  {
    "uri": "openorg",
    "description": "Provides OpenOrg linked-data describing an organization's structure and key facts in RDF/JSON-LD format.",
    "reference": "OpenOrg Data Initiative",
    "status": "permanent"
  },
  {
    "uri": "oslc",
    "description": "Provides OASIS OSLC Core v3.0 service provider discovery for lifecycle integration tools.",
    "reference": "OASIS OSLC Core v3.0",
    "status": "permanent"
  },
  {
    "uri": "pki-validation",
    "description": "Used by Certificate Authorities for domain control validation during TLS certificate issuance per CA/B Forum rules.",
    "reference": "CA/Browser Forum Baseline Requirements",
    "status": "permanent"
  },
  {
    "uri": "posh",
    "description": "Provides PKIX Over Secure HTTP (POSH) certificates for service authentication via HTTPS delegation.",
    "reference": "RFC 7711",
    "status": "permanent"
  },
  {
    "uri": "privacy-sandbox-attestations.json",
    "description": "Declared Privacy Sandbox API attestations for enrolled origins; deprecated as of April 2026.",
    "reference": "Google Privacy Sandbox Attestation",
    "status": "deprecated"
  },
  {
    "uri": "private-token-issuer-directory",
    "description": "Provides a directory of Privacy Pass token issuers for anonymous authentication token issuance.",
    "reference": "RFC 9578",
    "status": "permanent"
  },
  {
    "uri": "probing.txt",
    "description": "Declares a server's policy on active network probing and measurement, informing researchers and scanners.",
    "reference": "RFC 9511",
    "status": "permanent"
  },
  {
    "uri": "pvd",
    "description": "Provides Provisioning Domain (PvD) additional information for network configuration and policy discovery.",
    "reference": "RFC 8801",
    "status": "permanent"
  },
  {
    "uri": "rd",
    "description": "Provides a CoRE Resource Directory endpoint for IoT device registration and resource lookup.",
    "reference": "RFC 9176",
    "status": "permanent"
  },
  {
    "uri": "related-website-set.json",
    "description": "Declared a Related Website Set (formerly First-Party Sets) grouping related domains; deprecated April 2026.",
    "reference": "Chrome Related Website Sets Specification",
    "status": "deprecated"
  },
  {
    "uri": "reload-config",
    "description": "Provides REsource LOcation And Discovery (RELOAD) protocol overlay configuration for P2P communications.",
    "reference": "RFC 6940",
    "status": "permanent"
  },
  {
    "uri": "repute-template",
    "description": "Provides a URI template for querying reputation information about identifiers per the REPUTE protocol.",
    "reference": "RFC 7072",
    "status": "permanent"
  },
  {
    "uri": "resourcesync",
    "description": "Provides ResourceSync framework description documents for web resource synchronization between servers.",
    "reference": "ANSI/NISO Z39.99 ResourceSync",
    "status": "permanent"
  },
  {
    "uri": "sbom",
    "description": "Provides a Software Bill of Materials (SBOM) or a link to SBOMs for components at this origin.",
    "reference": "RFC 9472",
    "status": "permanent"
  },
  {
    "uri": "scitt-keys",
    "description": "Publishes the verification keys of a SCITT (Supply Chain Integrity, Transparency and Trust) Transparency Service.",
    "reference": "draft-ietf-scitt-scrapi (SCITT Reference APIs, in RFC Editor queue)",
    "status": "permanent"
  },
  {
    "uri": "security.txt",
    "description": "A standardized file for disclosing security contact information and vulnerability disclosure policies.",
    "reference": "RFC 9116",
    "status": "permanent"
  },
  {
    "uri": "ssf-configuration",
    "description": "Provides OpenID Shared Signals Framework (SSF) transmitter configuration metadata for security event sharing.",
    "reference": "OpenID Shared Signals Framework 1.0",
    "status": "provisional"
  },
  {
    "uri": "ssh-known-hosts",
    "description": "Provides a list of SSH host keys for the domain to aid SSH clients in verifying host authenticity.",
    "reference": "C2SP Well-Known SSH Hosts Specification",
    "status": "provisional"
  },
  {
    "uri": "sshfp",
    "description": "Provides SSH fingerprint records over HTTPS as an alternative to SSHFP DNS records for host verification.",
    "reference": "SSHFP Specification",
    "status": "provisional"
  },
  {
    "uri": "stun-key",
    "description": "Provides third-party STUN/TURN long-term credential keys for WebRTC authentication.",
    "reference": "RFC 7635",
    "status": "permanent"
  },
  {
    "uri": "tdmrep.json",
    "description": "Publishes a Text and Data Mining (TDM) policy for the site, declaring permissions for automated content mining.",
    "reference": "W3C TDM Representation Specification",
    "status": "provisional"
  },
  {
    "uri": "tea",
    "description": "Provides Transparency Exchange API (TEA) endpoint for accessing software transparency and SBOM data.",
    "reference": "ECMA TC54 TEA Specification",
    "status": "provisional"
  },
  {
    "uri": "terraform.json",
    "description": "Provides HashiCorp Terraform remote service discovery for locating module registry and other service endpoints.",
    "reference": "HashiCorp Terraform Remote Service Discovery",
    "status": "provisional"
  },
  {
    "uri": "thread",
    "description": "Provides Thread Group network device discovery and commissioning information for IoT mesh networking.",
    "reference": "Thread Group Specifications",
    "status": "permanent"
  },
  {
    "uri": "time",
    "description": "Provides a simple plain-text time service returning the current UTC time for lightweight clock synchronization.",
    "reference": "Poul-Henning Kamp Time Protocol",
    "status": "permanent"
  },
  {
    "uri": "timezone",
    "description": "Provides timezone data access and discovery per the Time Zone Data Distribution Service protocol.",
    "reference": "RFC 7808",
    "status": "permanent"
  },
  {
    "uri": "tor-relay",
    "description": "Publishes metadata about a Tor relay hosted at the domain for the Tor anonymity network.",
    "reference": "Tor Project Specification Proposal 326",
    "status": "provisional"
  },
  {
    "uri": "tpcd",
    "description": "Was used for third-party cookie deprecation grace period opt-out for the Chrome Privacy Sandbox; deprecated.",
    "reference": "Chrome 3PCD Grace Period Opt-Out Specification",
    "status": "deprecated"
  },
  {
    "uri": "traffic-advice",
    "description": "Provides traffic advice for intermediaries (e.g., prefetch proxies) declaring per-path fetch policies.",
    "reference": "Private Prefetch Proxy Specification",
    "status": "provisional"
  },
  {
    "uri": "trust.txt",
    "description": "Publishes a trust.txt file linking a news organization to its authoritative membership associations.",
    "reference": "JournalList trust.txt Reference Document",
    "status": "provisional"
  },
  {
    "uri": "uma2-configuration",
    "description": "Provides User-Managed Access (UMA) 2.0 authorization server metadata for delegated authorization.",
    "reference": "UMA 2.0 Grant for OAuth 2.0",
    "status": "permanent"
  },
  {
    "uri": "vacation-rental.json",
    "description": "Machine-readable vacation rental listing metadata defined by the Vacation Rental Protocol.",
    "reference": "Vacation Rental Protocol Specification v0.1",
    "status": "provisional"
  },
  {
    "uri": "void",
    "description": "Provides a VoID (Vocabulary of Interlinked Datasets) description of the RDF datasets published at the host.",
    "reference": "W3C Vocabulary of Interlinked Datasets",
    "status": "permanent"
  },
  {
    "uri": "webauthn",
    "description": "Provides relying party WebAuthn configuration including allowed origins and authentication policy metadata.",
    "reference": "W3C Web Authentication Level 3",
    "status": "permanent"
  },
  {
    "uri": "webfinger",
    "description": "Provides WebFinger resource discovery, returning JSON Resource Descriptors (JRDs) about users or services.",
    "reference": "RFC 7033",
    "status": "permanent"
  },
  {
    "uri": "webhook-authorized-senders.json",
    "description": "Lists authorized webhook sender domains and IP ranges that may deliver payloads to this endpoint.",
    "reference": "Intempus Webhook Authorization Specification",
    "status": "permanent"
  },
  {
    "uri": "webweaver.json",
    "description": "Provides WebWeaver service metadata for semantic web integration and linked data discovery.",
    "reference": "WebWeaver Well-Known Specification",
    "status": "provisional"
  },
  {
    "uri": "wot",
    "description": "Provides W3C Web of Things (WoT) Thing Description discovery for IoT device capability advertising.",
    "reference": "W3C WoT Discovery Specification",
    "status": "permanent"
  },
  {
    "uri": "xregistry",
    "description": "Discovery endpoint for an xRegistry server, exposing registries of schemas, endpoints and message definitions.",
    "reference": "xRegistry Core Specification v1",
    "status": "provisional"
  }
]