iana-registries-mcp-server
An MCP server that provides access to official IANA protocol registries and RFC status. It allows agents to look up service ports, MIME types, HTTP status codes and headers, URI schemes, Private Enterprise Numbers, and BCP 47 language tags. It also supports searching any IANA registry and reading specific registry records via XML filtering.
Endpoint and access
No sign-in to connect and list tools. Individual tools may still need a vendor account, credentials, or permissions; check the documented prerequisites.
MCP endpoint (Streamable HTTP)
https://iana-registries.caseyjhand.com/mcpWhat its tools do
10 tools, grouped by the hints the server advertises. Hints are self-declared, not verified behavior.
Checks and signals
Each line is separate evidence, not a trust score.
- Passed Endpoint answered the live check ·
- Availability 1 of 1 checks passed in 30 days
What you can do with it
- Look up IANA service name and transport protocol port assignments
- Find registered media (MIME) types by exact name or keyword
- Check the current status and relations of RFCs or Internet-Drafts
- Search and read records from any IANA XML registry
Source and maintenance
Community listingRegistry 0.3.0
- Maintenance checked
Protocol and capabilities
- Server
- iana-registries-mcp-server 0.3.0
- MCP protocol negotiated in check
- 2025-11-25
- Tools
- 10 advertised
- Resources
- 1 advertised
- Resource templates
- 1 advertised
- Prompts
- 0 advertised
Server-advertised capabilities
{
"tools": {
"listChanged": true
},
"logging": {},
"prompts": {
"listChanged": true
},
"resources": {
"subscribe": true,
"listChanged": true
},
"extensions": {
"io.modelcontextprotocol/skills": {
"directoryRead": true
}
}
}Server-provided instructions
Untrusted server output shown for inspection. It is not Koskamo guidance and is excluded from knowledge search.
Tools
10 advertised
iana_lookup_port — Look up a port assignment
Advertised read-onlyOpen-world
Look up IANA service name and transport protocol port assignments. Pass exactly one of `port` (a number, 0–65535), `service` (an exact service name such as "postgresql"), or `keyword` (words matched against service names and descriptions). Results list every transport (tcp, udp, sctp, dccp) separately, report the registry range row containing an unassigned port, and classify the port as System (0–1023), User (1024–49151), or Dynamic/Private (49152–65535). Service names registered without a port (DNS-SD names) appear with no port.
iana_lookup_port input schema
{
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"port": {
"type": "integer",
"maximum": 65535,
"minimum": 0,
"description": "Port number, 0–65535 (a digit string such as \"443\" also works). Returns every row for that port plus the range row containing it. Pass exactly one of port, service, or keyword."
},
"limit": {
"type": "integer",
"default": 25,
"maximum": 1000000,
"minimum": 1,
"description": "Requested maximum results, 1–1,000,000; values above 100 are clamped to 100 and disclosed as requested_limit and effective_limit. Default 25."
},
"offset": {
"type": "integer",
"default": 0,
"maximum": 9007199254740991,
"minimum": 0,
"description": "Number of keyword matches to skip; pass the next_offset of the previous response to get the next page. Default 0."
},
"keyword": {
"type": "string",
"maxLength": 100,
"minLength": 2,
"description": "Words matched as whole tokens against service names and descriptions, e.g. \"network time\". Pass exactly one of port, service, or keyword."
},
"service": {
"type": "string",
"pattern": "^[A-Za-z0-9+*/._-]{1,15}$",
"description": "Exact service name, case-insensitive, up to 15 characters, e.g. \"postgresql\" or \"whois++\". Pass exactly one of port, service, or keyword."
},
"transport": {
"enum": [
"tcp",
"udp",
"sctp",
"dccp"
],
"type": "string",
"description": "Keep only rows for this transport protocol. Rows without a transport (most range rows and every service name without a port) are always kept. Applies to every mode."
}
},
"additionalProperties": false
}iana_lookup_port output schema
{
"type": "object",
"anyOf": [
{
"not": {
"required": [
"error"
]
},
"required": [
"mode",
"found",
"assignments",
"source",
"totalCount",
"shown",
"cap",
"truncated"
]
},
{
"required": [
"error"
]
}
],
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"cap": {
"type": "number",
"description": "The limit applied."
},
"mode": {
"enum": [
"port",
"service",
"keyword"
],
"type": "string",
"description": "Which lookup ran."
},
"error": {
"type": "object",
"required": [
"code",
"message"
],
"properties": {
"code": {
"type": "integer",
"maximum": 9007199254740991,
"minimum": -9007199254740991,
"description": "JSON-RPC error code for this failure."
},
"data": {
"type": "object",
"properties": {
"reason": {
"type": "string",
"examples": [
"mode_required",
"upstream_unreadable",
"pacer_shed"
],
"description": "Machine-readable failure mode. Declared by this tool: `mode_required`: None, or more than one, of port, service, and keyword was given. `upstream_unreadable`: The port registry file could not be fetched, was larger than this server accepts, or parsed to zero records. `pacer_shed`: This server's own iana.org request queue is too full for the call to start in time. Other values are possible when a failure originates below the handler."
},
"recovery": {
"type": "object",
"required": [
"hint"
],
"properties": {
"hint": {
"type": "string"
}
},
"description": "Actionable next step for the caller.",
"additionalProperties": {}
},
"retryable": {
"type": "boolean",
"description": "Whether retrying may succeed."
}
},
"additionalProperties": {}
},
"message": {
"type": "string",
"description": "Human-readable description of what went wrong."
}
},
"description": "Present when the call failed. Absent on success.",
"additionalProperties": {}
},
"found": {
"type": "boolean",
"description": "True when a matching row after transport filtering has a registered service name; keyword mode checks all matches before paging."
},
"shown": {
"type": "number",
"description": "Results returned."
},
"notice": {
"type": "string",
"description": "Guidance on a miss, a cut list, or another condition."
},
"source": {
"type": "object",
"required": [
"registry_id",
"url",
"fetched_at",
"stale"
],
"properties": {
"url": {
"type": "string",
"description": "The file fetched from iana.org."
},
"stale": {
"type": "boolean",
"description": "True when a refresh failed and a cached copy up to 7 days old answered."
},
"fetched_at": {
"type": "string",
"description": "ISO 8601 time of the last successful fetch or revalidation."
},
"registry_id": {
"type": "string",
"description": "Id of the registry file that answered."
},
"registry_updated": {
"type": "string",
"description": "The registry's own last-updated date; absent for the protocol index."
}
},
"description": "Provenance and freshness of the answer.",
"additionalProperties": false
},
"truncated": {
"type": "boolean",
"description": "True when more matches exist than were returned."
},
"port_class": {
"type": "object",
"required": [
"name",
"range"
],
"properties": {
"name": {
"enum": [
"system",
"user",
"dynamic"
],
"type": "string",
"description": "RFC 6335 port class."
},
"range": {
"type": "string",
"description": "The class range, e.g. \"0-1023\"."
}
},
"description": "Port mode: the requested port's class.",
"additionalProperties": false
},
"totalCount": {
"type": "number",
"description": "Matches before the limit was applied."
},
"assignments": {
"type": "array",
"items": {
"type": "object",
"required": [
"state",
"references"
],
"properties": {
"port": {
"type": "number",
"description": "Port number of a single-port row."
},
"notes": {
"type": "string",
"description": "Registry note."
},
"state": {
"enum": [
"assigned",
"reserved",
"unassigned",
"unnamed"
],
"type": "string",
"description": "assigned (service name present), reserved or unassigned (the description is that word), else unnamed (e.g. \"De-registered\")."
},
"updated": {
"type": "string",
"description": "Last-updated date."
},
"transport": {
"type": "string",
"description": "tcp, udp, sctp, or dccp; usually absent on range rows."
},
"port_range": {
"type": "string",
"description": "Range of a range row, e.g. \"1002-1007\"."
},
"references": {
"type": "array",
"items": {
"type": "object",
"required": [
"type",
"id"
],
"properties": {
"id": {
"type": "string",
"description": "E.g. \"RFC 9110\", a draft name, a registry id, or a URL."
},
"url": {
"type": "string",
"description": "URL of the reference."
},
"type": {
"enum": [
"rfc",
"draft",
"uri",
"registry",
"rfc-errata",
"note",
"text"
],
"type": "string",
"description": "Reference kind."
},
"label": {
"type": "string",
"description": "Label text, when it adds to id and section."
},
"section": {
"type": "string",
"description": "Section, e.g. \"15.5.5\"."
}
},
"description": "A defining reference.",
"additionalProperties": false
},
"description": "Defining references."
},
"registered": {
"type": "string",
"description": "Registration date."
},
"description": {
"type": "string",
"description": "Registry description."
},
"service_name": {
"type": "string",
"description": "Registered service name; absent on range and unnamed rows."
},
"unauthorized_use": {
"type": "string",
"description": "Known unauthorized use, as recorded."
}
},
"description": "One registry row.",
"additionalProperties": false
},
"description": "Matching rows. Port mode: exact rows, then range rows containing the port. Other modes: ascending by port, port-less rows last."
},
"next_offset": {
"type": "number",
"description": "Pass as offset for the next page; absent on the last."
},
"effective_limit": {
"type": "number",
"description": "The response limit after clamping, present when clamped."
},
"requested_limit": {
"type": "number",
"description": "The requested limit, present when clamped."
}
},
"additionalProperties": false
}iana_lookup_port annotations
{
"readOnlyHint": true,
"openWorldHint": true,
"idempotentHint": true
}iana_lookup_media_type — Look up a media type
Advertised read-onlyOpen-world
Look up registered media (MIME) types. Pass exactly one of `type` (a full name such as "application/json"; parameters after ";" are ignored) or `keyword` (words matched against registered type names and status annotations, e.g. "geo json"; never against file extensions). An exact `type` lookup also reads the registration template and returns its file-extension, intended-usage, and deprecated-alias statements as written, each only when the template has it. Some registered types have no registration template (`template.available: false`); their references are the defining documents. Deprecated and obsoleted types are reported with their replacement when the registry names one. Unregistered "x-" types are not in the registry.
iana_lookup_media_type input schema
{
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"type": {
"type": "string",
"pattern": "^[a-z0-9][a-z0-9!#$&^_.+-]{0,126}\\/[a-z0-9][a-z0-9!#$&^_.+-]{0,126}$",
"description": "Full media type, case-insensitive, e.g. \"application/json\" (\"; charset=utf-8\" and other parameters are dropped). Pass this or keyword, not both."
},
"limit": {
"type": "integer",
"default": 25,
"maximum": 1000000,
"minimum": 1,
"description": "Requested maximum results, 1–1,000,000; values above 100 are clamped to 100 and disclosed as requested_limit and effective_limit. Default 25."
},
"offset": {
"type": "integer",
"default": 0,
"maximum": 9007199254740991,
"minimum": 0,
"description": "Number of keyword matches to skip; pass the next_offset of the previous response to get the next page. Default 0."
},
"keyword": {
"type": "string",
"maxLength": 100,
"minLength": 2,
"description": "Words matched as whole tokens against registered type names and status annotations, e.g. \"geo json\". File extensions are not searched: look up the expected type with type to read its template's file-extension statement, when the template has one. Pass this or type, not both."
},
"top_level": {
"enum": [
"application",
"audio",
"example",
"font",
"haptics",
"image",
"message",
"model",
"multipart",
"text",
"video"
],
"type": "string",
"description": "Keep only types under this top-level type, e.g. \"image\". Keyword mode only."
}
},
"additionalProperties": false
}iana_lookup_media_type output schema
{
"type": "object",
"anyOf": [
{
"not": {
"required": [
"error"
]
},
"required": [
"mode",
"found",
"media_types",
"source",
"totalCount",
"shown",
"cap",
"truncated"
]
},
{
"required": [
"error"
]
}
],
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"cap": {
"type": "number",
"description": "The limit applied."
},
"mode": {
"enum": [
"type",
"keyword"
],
"type": "string",
"description": "Which lookup ran."
},
"error": {
"type": "object",
"required": [
"code",
"message"
],
"properties": {
"code": {
"type": "integer",
"maximum": 9007199254740991,
"minimum": -9007199254740991,
"description": "JSON-RPC error code for this failure."
},
"data": {
"type": "object",
"properties": {
"reason": {
"type": "string",
"examples": [
"mode_required",
"upstream_unreadable",
"pacer_shed"
],
"description": "Machine-readable failure mode. Declared by this tool: `mode_required`: Neither or both of type and keyword were given. `upstream_unreadable`: The media type registry file could not be fetched or parsed. `pacer_shed`: This server's own iana.org request queue is too full for the call to start in time. Other values are possible when a failure originates below the handler."
},
"recovery": {
"type": "object",
"required": [
"hint"
],
"properties": {
"hint": {
"type": "string"
}
},
"description": "Actionable next step for the caller.",
"additionalProperties": {}
},
"retryable": {
"type": "boolean",
"description": "Whether retrying may succeed."
}
},
"additionalProperties": {}
},
"message": {
"type": "string",
"description": "Human-readable description of what went wrong."
}
},
"description": "Present when the call failed. Absent on success.",
"additionalProperties": {}
},
"found": {
"type": "boolean",
"description": "True when a registered media type matched."
},
"shown": {
"type": "number",
"description": "Results returned."
},
"notice": {
"type": "string",
"description": "Guidance on a miss, a cut list, or another condition."
},
"source": {
"type": "object",
"required": [
"registry_id",
"url",
"fetched_at",
"stale"
],
"properties": {
"url": {
"type": "string",
"description": "The file fetched from iana.org."
},
"stale": {
"type": "boolean",
"description": "True when a refresh failed and a cached copy up to 7 days old answered."
},
"fetched_at": {
"type": "string",
"description": "ISO 8601 time of the last successful fetch or revalidation."
},
"registry_id": {
"type": "string",
"description": "Id of the registry file that answered."
},
"registry_updated": {
"type": "string",
"description": "The registry's own last-updated date; absent for the protocol index."
}
},
"description": "Provenance and freshness of the answer.",
"additionalProperties": false
},
"truncated": {
"type": "boolean",
"description": "True when more matches exist than were returned."
},
"totalCount": {
"type": "number",
"description": "Matches before the limit was applied."
},
"media_types": {
"type": "array",
"items": {
"type": "object",
"required": [
"type",
"top_level",
"subtype",
"status",
"template_url",
"references"
],
"properties": {
"type": {
"type": "string",
"description": "type/subtype in registry casing, e.g. \"application/json\"."
},
"status": {
"enum": [
"current",
"deprecated",
"obsoleted"
],
"type": "string",
"description": "From the registry annotation (OBSOLETE(D), DEPRECATED); else current."
},
"subtype": {
"type": "string",
"description": "Subtype, e.g. \"json\"."
},
"updated": {
"type": "string",
"description": "Last-updated date."
},
"template": {
"type": "object",
"required": [
"fetched"
],
"properties": {
"fetched": {
"type": "boolean",
"description": "False when the template could not be read."
},
"available": {
"type": "boolean",
"description": "True when a template was read; false when IANA publishes no registration template for this type, so its references are its defining documents. Absent when fetched is false."
},
"intended_usage": {
"type": "string",
"description": "The \"Intended usage\" statement, e.g. \"COMMON\"."
},
"file_extensions": {
"type": "string",
"description": "The \"File extension(s)\" statement as written, e.g. \".json\"."
},
"deprecated_aliases": {
"type": "string",
"description": "The \"Deprecated alias names for this type\" statement."
}
},
"description": "Type mode: the registration template read; each statement absent when the template lacks it.",
"additionalProperties": false
},
"top_level": {
"type": "string",
"description": "Top-level type, e.g. \"application\"."
},
"references": {
"type": "array",
"items": {
"type": "object",
"required": [
"type",
"id"
],
"properties": {
"id": {
"type": "string",
"description": "E.g. \"RFC 9110\", a draft name, a registry id, or a URL."
},
"url": {
"type": "string",
"description": "URL of the reference."
},
"type": {
"enum": [
"rfc",
"draft",
"uri",
"registry",
"rfc-errata",
"note",
"text"
],
"type": "string",
"description": "Reference kind."
},
"label": {
"type": "string",
"description": "Label text, when it adds to id and section."
},
"section": {
"type": "string",
"description": "Section, e.g. \"15.5.5\"."
}
},
"description": "A defining reference.",
"additionalProperties": false
},
"description": "Defining references."
},
"registered": {
"type": "string",
"description": "Registration date."
},
"replaced_by": {
"type": "string",
"description": "The replacement type the annotation names."
},
"status_note": {
"type": "string",
"description": "The status annotation, e.g. \"OBSOLETED in favor of text/javascript\"."
},
"template_url": {
"type": "string",
"description": "Registration template URL."
}
},
"description": "One registered media type.",
"additionalProperties": false
},
"description": "Matching media types: exact name hits first, then registry order."
},
"next_offset": {
"type": "number",
"description": "Pass as offset for the next page; absent on the last."
},
"effective_limit": {
"type": "number",
"description": "The response limit after clamping, present when clamped."
},
"normalized_type": {
"type": "string",
"description": "Type mode: the type looked up, lowercased, parameters removed."
},
"requested_limit": {
"type": "number",
"description": "The requested limit, present when clamped."
}
},
"additionalProperties": false
}iana_lookup_media_type annotations
{
"readOnlyHint": true,
"openWorldHint": true,
"idempotentHint": true
}iana_lookup_http_status — Look up an HTTP status code
Advertised read-onlyOpen-world
Look up an HTTP status code in the IANA registry, or search reason phrases. Pass exactly one of `code` (100–599) or `keyword` (e.g. "too many"). Returns the registered phrase, its class, defining reference with section, and whether it is temporary, obsoleted, or unused; an unassigned code returns found: false with the unassigned range it falls in.
iana_lookup_http_status input schema
{
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"code": {
"type": "integer",
"maximum": 599,
"minimum": 100,
"description": "Status code to look up, 100–599 (a digit string such as \"429\" also works). Pass this or keyword, not both."
},
"limit": {
"type": "integer",
"default": 25,
"maximum": 1000000,
"minimum": 1,
"description": "Requested maximum results, 1–1,000,000; values above 100 are clamped to 100 and disclosed as requested_limit and effective_limit. Default 25."
},
"offset": {
"type": "integer",
"default": 0,
"maximum": 9007199254740991,
"minimum": 0,
"description": "Number of keyword matches to skip; pass the next_offset of the previous response to get the next page. Default 0."
},
"keyword": {
"type": "string",
"maxLength": 100,
"minLength": 2,
"description": "Words matched as whole tokens against registered reason phrases, e.g. \"too many\" or \"gateway\". Pass this or code, not both."
}
},
"additionalProperties": false
}iana_lookup_http_status output schema
{
"type": "object",
"anyOf": [
{
"not": {
"required": [
"error"
]
},
"required": [
"mode",
"found",
"statuses",
"source",
"totalCount",
"shown",
"cap",
"truncated"
]
},
{
"required": [
"error"
]
}
],
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"cap": {
"type": "number",
"description": "The limit applied."
},
"mode": {
"enum": [
"code",
"keyword"
],
"type": "string",
"description": "Which lookup ran."
},
"error": {
"type": "object",
"required": [
"code",
"message"
],
"properties": {
"code": {
"type": "integer",
"maximum": 9007199254740991,
"minimum": -9007199254740991,
"description": "JSON-RPC error code for this failure."
},
"data": {
"type": "object",
"properties": {
"reason": {
"type": "string",
"examples": [
"mode_required",
"upstream_unreadable",
"pacer_shed"
],
"description": "Machine-readable failure mode. Declared by this tool: `mode_required`: Neither or both of code and keyword were given. `upstream_unreadable`: The HTTP status registry file could not be fetched or parsed. `pacer_shed`: This server's own iana.org request queue is too full for the call to start in time. Other values are possible when a failure originates below the handler."
},
"recovery": {
"type": "object",
"required": [
"hint"
],
"properties": {
"hint": {
"type": "string"
}
},
"description": "Actionable next step for the caller.",
"additionalProperties": {}
},
"retryable": {
"type": "boolean",
"description": "Whether retrying may succeed."
}
},
"additionalProperties": {}
},
"message": {
"type": "string",
"description": "Human-readable description of what went wrong."
}
},
"description": "Present when the call failed. Absent on success.",
"additionalProperties": {}
},
"found": {
"type": "boolean",
"description": "True when a registered status matched."
},
"shown": {
"type": "number",
"description": "Results returned."
},
"notice": {
"type": "string",
"description": "Guidance on a miss, a cut list, or another condition."
},
"source": {
"type": "object",
"required": [
"registry_id",
"url",
"fetched_at",
"stale"
],
"properties": {
"url": {
"type": "string",
"description": "The file fetched from iana.org."
},
"stale": {
"type": "boolean",
"description": "True when a refresh failed and a cached copy up to 7 days old answered."
},
"fetched_at": {
"type": "string",
"description": "ISO 8601 time of the last successful fetch or revalidation."
},
"registry_id": {
"type": "string",
"description": "Id of the registry file that answered."
},
"registry_updated": {
"type": "string",
"description": "The registry's own last-updated date; absent for the protocol index."
}
},
"description": "Provenance and freshness of the answer.",
"additionalProperties": false
},
"statuses": {
"type": "array",
"items": {
"type": "object",
"required": [
"code",
"phrase",
"class",
"state",
"references"
],
"properties": {
"code": {
"type": "number",
"description": "The status code."
},
"class": {
"enum": [
"informational",
"success",
"redirection",
"client_error",
"server_error"
],
"type": "string",
"description": "Status class from the first digit."
},
"state": {
"enum": [
"assigned",
"temporary",
"obsoleted",
"unused"
],
"type": "string",
"description": "From the registry markers (Unused), (OBSOLETED), (TEMPORARY - …)."
},
"phrase": {
"type": "string",
"description": "The registered description, with markers such as \"(Unused)\"."
},
"updated": {
"type": "string",
"description": "Last-updated date."
},
"references": {
"type": "array",
"items": {
"type": "object",
"required": [
"type",
"id"
],
"properties": {
"id": {
"type": "string",
"description": "E.g. \"RFC 9110\", a draft name, a registry id, or a URL."
},
"url": {
"type": "string",
"description": "URL of the reference."
},
"type": {
"enum": [
"rfc",
"draft",
"uri",
"registry",
"rfc-errata",
"note",
"text"
],
"type": "string",
"description": "Reference kind."
},
"label": {
"type": "string",
"description": "Label text, when it adds to id and section."
},
"section": {
"type": "string",
"description": "Section, e.g. \"15.5.5\"."
}
},
"description": "A defining reference.",
"additionalProperties": false
},
"description": "Defining references."
},
"registered": {
"type": "string",
"description": "Registration date."
}
},
"description": "One registered status code.",
"additionalProperties": false
},
"description": "Matching status codes: exact phrase hits first, then registry order."
},
"truncated": {
"type": "boolean",
"description": "True when more matches exist than were returned."
},
"totalCount": {
"type": "number",
"description": "Matches before the limit was applied."
},
"next_offset": {
"type": "number",
"description": "Pass as offset for the next page; absent on the last."
},
"effective_limit": {
"type": "number",
"description": "The response limit after clamping, present when clamped."
},
"requested_limit": {
"type": "number",
"description": "The requested limit, present when clamped."
},
"unassigned_range": {
"type": "string",
"description": "For an unassigned code, the registry range it falls in, e.g. \"432-450\"."
}
},
"additionalProperties": false
}iana_lookup_http_status annotations
{
"readOnlyHint": true,
"openWorldHint": true,
"idempotentHint": true
}iana_lookup_http_field — Look up an HTTP field name
Advertised read-onlyOpen-world
Look up a registered HTTP field (header or trailer) name. Pass exactly one of `name` (case-insensitive, e.g. "Cache-Status") or `keyword` (words matched against field names and comments). Returns the registration status — permanent, provisional, deprecated, or obsoleted — the Structured Field type when registered, and the defining reference. Many widely used headers are unregistered; a miss means only that IANA has no entry.
iana_lookup_http_field input schema
{
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"name": {
"type": "string",
"pattern": "^[!#$%&'*+.^_`|~0-9A-Za-z-]{1,100}$",
"description": "Exact field name, case-insensitive, e.g. \"Content-Type\" (a trailing \":\" is ignored). Pass this or keyword, not both."
},
"limit": {
"type": "integer",
"default": 25,
"maximum": 1000000,
"minimum": 1,
"description": "Requested maximum results, 1–1,000,000; values above 100 are clamped to 100 and disclosed as requested_limit and effective_limit. Default 25."
},
"offset": {
"type": "integer",
"default": 0,
"maximum": 9007199254740991,
"minimum": 0,
"description": "Number of keyword matches to skip; pass the next_offset of the previous response to get the next page. Default 0."
},
"status": {
"enum": [
"permanent",
"provisional",
"deprecated",
"obsoleted"
],
"type": "string",
"description": "Keep only fields with this registration status. Applies to both modes."
},
"keyword": {
"type": "string",
"maxLength": 100,
"minLength": 2,
"description": "Words matched as whole tokens against field names and registry comments, e.g. \"cache\". Pass this or name, not both."
}
},
"additionalProperties": false
}iana_lookup_http_field output schema
{
"type": "object",
"anyOf": [
{
"not": {
"required": [
"error"
]
},
"required": [
"mode",
"found",
"fields",
"source",
"totalCount",
"shown",
"cap",
"truncated"
]
},
{
"required": [
"error"
]
}
],
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"cap": {
"type": "number",
"description": "The limit applied."
},
"mode": {
"enum": [
"name",
"keyword"
],
"type": "string",
"description": "Which lookup ran."
},
"error": {
"type": "object",
"required": [
"code",
"message"
],
"properties": {
"code": {
"type": "integer",
"maximum": 9007199254740991,
"minimum": -9007199254740991,
"description": "JSON-RPC error code for this failure."
},
"data": {
"type": "object",
"properties": {
"reason": {
"type": "string",
"examples": [
"mode_required",
"upstream_unreadable",
"pacer_shed"
],
"description": "Machine-readable failure mode. Declared by this tool: `mode_required`: Neither or both of name and keyword were given. `upstream_unreadable`: The HTTP field registry file could not be fetched or parsed. `pacer_shed`: This server's own iana.org request queue is too full for the call to start in time. Other values are possible when a failure originates below the handler."
},
"recovery": {
"type": "object",
"required": [
"hint"
],
"properties": {
"hint": {
"type": "string"
}
},
"description": "Actionable next step for the caller.",
"additionalProperties": {}
},
"retryable": {
"type": "boolean",
"description": "Whether retrying may succeed."
}
},
"additionalProperties": {}
},
"message": {
"type": "string",
"description": "Human-readable description of what went wrong."
}
},
"description": "Present when the call failed. Absent on success.",
"additionalProperties": {}
},
"found": {
"type": "boolean",
"description": "True when a registered field matched."
},
"shown": {
"type": "number",
"description": "Results returned."
},
"fields": {
"type": "array",
"items": {
"type": "object",
"required": [
"name",
"references"
],
"properties": {
"name": {
"type": "string",
"description": "The registered field name, registry casing."
},
"status": {
"type": "string",
"description": "Lowercased: permanent, provisional, deprecated, or obsoleted."
},
"updated": {
"type": "string",
"description": "Last-updated date."
},
"comments": {
"type": "string",
"description": "Registry comments."
},
"references": {
"type": "array",
"items": {
"type": "object",
"required": [
"type",
"id"
],
"properties": {
"id": {
"type": "string",
"description": "E.g. \"RFC 9110\", a draft name, a registry id, or a URL."
},
"url": {
"type": "string",
"description": "URL of the reference."
},
"type": {
"enum": [
"rfc",
"draft",
"uri",
"registry",
"rfc-errata",
"note",
"text"
],
"type": "string",
"description": "Reference kind."
},
"label": {
"type": "string",
"description": "Label text, when it adds to id and section."
},
"section": {
"type": "string",
"description": "Section, e.g. \"15.5.5\"."
}
},
"description": "A defining reference.",
"additionalProperties": false
},
"description": "Defining references."
},
"registered": {
"type": "string",
"description": "Registration date."
},
"structured_type": {
"type": "string",
"description": "Structured Field type (List, Dictionary, Item), when registered."
}
},
"description": "One registered HTTP field.",
"additionalProperties": false
},
"description": "Matching fields: exact name hits first, then registry order."
},
"notice": {
"type": "string",
"description": "Guidance on a miss, a cut list, or another condition."
},
"source": {
"type": "object",
"required": [
"registry_id",
"url",
"fetched_at",
"stale"
],
"properties": {
"url": {
"type": "string",
"description": "The file fetched from iana.org."
},
"stale": {
"type": "boolean",
"description": "True when a refresh failed and a cached copy up to 7 days old answered."
},
"fetched_at": {
"type": "string",
"description": "ISO 8601 time of the last successful fetch or revalidation."
},
"registry_id": {
"type": "string",
"description": "Id of the registry file that answered."
},
"registry_updated": {
"type": "string",
"description": "The registry's own last-updated date; absent for the protocol index."
}
},
"description": "Provenance and freshness of the answer.",
"additionalProperties": false
},
"truncated": {
"type": "boolean",
"description": "True when more matches exist than were returned."
},
"totalCount": {
"type": "number",
"description": "Matches before the limit was applied."
},
"next_offset": {
"type": "number",
"description": "Pass as offset for the next page; absent on the last."
},
"effective_limit": {
"type": "number",
"description": "The response limit after clamping, present when clamped."
},
"requested_limit": {
"type": "number",
"description": "The requested limit, present when clamped."
}
},
"additionalProperties": false
}iana_lookup_http_field annotations
{
"readOnlyHint": true,
"openWorldHint": true,
"idempotentHint": true
}iana_lookup_uri_scheme — Look up a URI scheme
Advertised read-onlyOpen-world
Look up a registered URI scheme. Pass exactly one of `scheme` (e.g. "mailto"; a trailing ":" or "://" is ignored) or `keyword` (words matched against scheme names and descriptions). Returns the status — permanent, provisional, or historical — description, references, and well-known URI support.
iana_lookup_uri_scheme input schema
{
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"limit": {
"type": "integer",
"default": 25,
"maximum": 1000000,
"minimum": 1,
"description": "Requested maximum results, 1–1,000,000; values above 100 are clamped to 100 and disclosed as requested_limit and effective_limit. Default 25."
},
"offset": {
"type": "integer",
"default": 0,
"maximum": 9007199254740991,
"minimum": 0,
"description": "Number of keyword matches to skip; pass the next_offset of the previous response to get the next page. Default 0."
},
"scheme": {
"type": "string",
"pattern": "^[a-z][a-z0-9+.-]{0,63}$",
"description": "Exact scheme name, case-insensitive, e.g. \"https\" (a trailing \":\" or \"://\" is ignored). Pass this or keyword, not both."
},
"status": {
"enum": [
"permanent",
"provisional",
"historical"
],
"type": "string",
"description": "Keep only schemes with this registration status. Applies to both modes."
},
"keyword": {
"type": "string",
"maxLength": 100,
"minLength": 2,
"description": "Words matched as whole tokens against scheme names and descriptions, e.g. \"websocket\". Pass this or scheme, not both."
}
},
"additionalProperties": false
}iana_lookup_uri_scheme output schema
{
"type": "object",
"anyOf": [
{
"not": {
"required": [
"error"
]
},
"required": [
"mode",
"found",
"schemes",
"source",
"totalCount",
"shown",
"cap",
"truncated"
]
},
{
"required": [
"error"
]
}
],
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"cap": {
"type": "number",
"description": "The limit applied."
},
"mode": {
"enum": [
"scheme",
"keyword"
],
"type": "string",
"description": "Which lookup ran."
},
"error": {
"type": "object",
"required": [
"code",
"message"
],
"properties": {
"code": {
"type": "integer",
"maximum": 9007199254740991,
"minimum": -9007199254740991,
"description": "JSON-RPC error code for this failure."
},
"data": {
"type": "object",
"properties": {
"reason": {
"type": "string",
"examples": [
"mode_required",
"upstream_unreadable",
"pacer_shed"
],
"description": "Machine-readable failure mode. Declared by this tool: `mode_required`: Neither or both of scheme and keyword were given. `upstream_unreadable`: The URI scheme registry file could not be fetched or parsed. `pacer_shed`: This server's own iana.org request queue is too full for the call to start in time. Other values are possible when a failure originates below the handler."
},
"recovery": {
"type": "object",
"required": [
"hint"
],
"properties": {
"hint": {
"type": "string"
}
},
"description": "Actionable next step for the caller.",
"additionalProperties": {}
},
"retryable": {
"type": "boolean",
"description": "Whether retrying may succeed."
}
},
"additionalProperties": {}
},
"message": {
"type": "string",
"description": "Human-readable description of what went wrong."
}
},
"description": "Present when the call failed. Absent on success.",
"additionalProperties": {}
},
"found": {
"type": "boolean",
"description": "True when a registered scheme matched."
},
"shown": {
"type": "number",
"description": "Results returned."
},
"notice": {
"type": "string",
"description": "Guidance on a miss, a cut list, or another condition."
},
"source": {
"type": "object",
"required": [
"registry_id",
"url",
"fetched_at",
"stale"
],
"properties": {
"url": {
"type": "string",
"description": "The file fetched from iana.org."
},
"stale": {
"type": "boolean",
"description": "True when a refresh failed and a cached copy up to 7 days old answered."
},
"fetched_at": {
"type": "string",
"description": "ISO 8601 time of the last successful fetch or revalidation."
},
"registry_id": {
"type": "string",
"description": "Id of the registry file that answered."
},
"registry_updated": {
"type": "string",
"description": "The registry's own last-updated date; absent for the protocol index."
}
},
"description": "Provenance and freshness of the answer.",
"additionalProperties": false
},
"schemes": {
"type": "array",
"items": {
"type": "object",
"required": [
"scheme",
"references"
],
"properties": {
"notes": {
"type": "string",
"description": "Registry notes."
},
"scheme": {
"type": "string",
"description": "The registered scheme name."
},
"status": {
"type": "string",
"description": "Lowercased: permanent, provisional, or historical."
},
"updated": {
"type": "string",
"description": "Last-updated date."
},
"references": {
"type": "array",
"items": {
"type": "object",
"required": [
"type",
"id"
],
"properties": {
"id": {
"type": "string",
"description": "E.g. \"RFC 9110\", a draft name, a registry id, or a URL."
},
"url": {
"type": "string",
"description": "URL of the reference."
},
"type": {
"enum": [
"rfc",
"draft",
"uri",
"registry",
"rfc-errata",
"note",
"text"
],
"type": "string",
"description": "Reference kind."
},
"label": {
"type": "string",
"description": "Label text, when it adds to id and section."
},
"section": {
"type": "string",
"description": "Section, e.g. \"15.5.5\"."
}
},
"description": "A defining reference.",
"additionalProperties": false
},
"description": "Defining references."
},
"registered": {
"type": "string",
"description": "Registration date."
},
"description": {
"type": "string",
"description": "Registry description."
},
"status_note": {
"type": "string",
"description": "Annotation on the registered name, e.g. \"OBSOLETE\"."
},
"template_url": {
"type": "string",
"description": "Registration template URL, when published."
},
"well_known_uri_support": {
"type": "string",
"description": "Reference defining well-known URI support, when any."
}
},
"description": "One registered URI scheme.",
"additionalProperties": false
},
"description": "Matching schemes: exact scheme hits first, then registry order."
},
"truncated": {
"type": "boolean",
"description": "True when more matches exist than were returned."
},
"totalCount": {
"type": "number",
"description": "Matches before the limit was applied."
},
"next_offset": {
"type": "number",
"description": "Pass as offset for the next page; absent on the last."
},
"effective_limit": {
"type": "number",
"description": "The response limit after clamping, present when clamped."
},
"requested_limit": {
"type": "number",
"description": "The requested limit, present when clamped."
}
},
"additionalProperties": false
}iana_lookup_uri_scheme annotations
{
"readOnlyHint": true,
"openWorldHint": true,
"idempotentHint": true
}iana_lookup_pen — Look up a Private Enterprise Number
Advertised read-onlyOpen-world
Look up a Private Enterprise Number (PEN). Pass exactly one of `pen` (a number such as 32473, or an OID under 1.3.6.1.4.1 such as 1.3.6.1.4.1.32473.1.2) or `organization` (words matched against organization names). Returns the organization and its OID prefix. Arcs below the enterprise number are assigned by the enterprise, not IANA. Contact details are not returned.
iana_lookup_pen input schema
{
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"pen": {
"type": "string",
"pattern": "^(?:\\s*|\\s*\\.?(?:\\d{1,9}|\\d{1,10}(?:\\.\\d{1,10}){2,70}|(?:[iI][sS][oO]\\.[oO][rR][gG]\\.[dD][oO][dD]\\.[iI][nN][tT][eE][rR][nN][eE][tT]\\.[pP][rR][iI][vV][aA][tT][eE]\\.[eE][nN][tT][eE][rR][pP][rR][iI][sS][eE][sS]|[iI][sS][oO]\\.[oO][rR][gG]\\.[dD][oO][dD]\\.[iI][nN][tT][eE][rR][nN][eE][tT]\\.[pP][rR][iI][vV][aA][tT][eE]\\.[eE][nN][tT][eE][rR][pP][rR][iI][sS][eE]|[sS][nN][mM][pP][vV]2-[sS][mM][iI]::[eE][nN][tT][eE][rR][pP][rR][iI][sS][eE][sS]|[eE][nN][tT][eE][rR][pP][rR][iI][sS][eE][sS]|[iI][sS][oO]\\.3\\.6\\.1\\.4\\.1)(?:\\.\\d{1,9}(?:\\.\\d{1,10}){0,64})?)\\s*)$",
"description": "Enterprise number, e.g. \"32473\", or an OID under 1.3.6.1.4.1 naming it, e.g. \"1.3.6.1.4.1.32473.1.2\". A leading dot, case-insensitive iso.3.6.1.4.1, iso.org.dod.internet.private.enterprise(s), enterprises, and SNMPv2-SMI::enterprises prefixes are accepted. Pass this or organization, not both."
},
"limit": {
"type": "integer",
"default": 25,
"maximum": 1000000,
"minimum": 1,
"description": "Requested maximum results, 1–1,000,000; values above 100 are clamped to 100 and disclosed as requested_limit and effective_limit. Default 25."
},
"offset": {
"type": "integer",
"default": 0,
"maximum": 9007199254740991,
"minimum": 0,
"description": "Number of organization matches to skip; pass the next_offset of the previous response to get the next page. Default 0."
},
"organization": {
"type": "string",
"maxLength": 100,
"minLength": 2,
"description": "Words matched as whole tokens against the names of assigned entries, e.g. \"cisco systems\"; look up a number with pen to see a reserved or unassigned one. Pass this or pen, not both."
}
},
"additionalProperties": false
}iana_lookup_pen output schema
{
"type": "object",
"anyOf": [
{
"not": {
"required": [
"error"
]
},
"required": [
"mode",
"found",
"enterprises",
"source",
"totalCount",
"shown",
"cap",
"truncated"
]
},
{
"required": [
"error"
]
}
],
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"cap": {
"type": "number",
"description": "The limit applied."
},
"mode": {
"enum": [
"pen",
"organization"
],
"type": "string",
"description": "Which lookup ran."
},
"error": {
"type": "object",
"required": [
"code",
"message"
],
"properties": {
"code": {
"type": "integer",
"maximum": 9007199254740991,
"minimum": -9007199254740991,
"description": "JSON-RPC error code for this failure."
},
"data": {
"type": "object",
"properties": {
"reason": {
"type": "string",
"examples": [
"outside_enterprise_arc",
"enterprise_number_required",
"mode_required",
"upstream_unreadable",
"pacer_shed"
],
"description": "Machine-readable failure mode. Declared by this tool: `outside_enterprise_arc`: The numeric OID is outside the private enterprise arc 1.3.6.1.4.1. `enterprise_number_required`: The OID names the enterprise arc itself without an enterprise number. `mode_required`: Neither or both of pen and organization were given. `upstream_unreadable`: The enterprise number file could not be fetched or parsed to zero records. `pacer_shed`: This server's own iana.org request queue is too full for the call to start in time. Other values are possible when a failure originates below the handler."
},
"recovery": {
"type": "object",
"required": [
"hint"
],
"properties": {
"hint": {
"type": "string"
}
},
"description": "Actionable next step for the caller.",
"additionalProperties": {}
},
"retryable": {
"type": "boolean",
"description": "Whether retrying may succeed."
}
},
"additionalProperties": {}
},
"message": {
"type": "string",
"description": "Human-readable description of what went wrong."
}
},
"description": "Present when the call failed. Absent on success.",
"additionalProperties": {}
},
"found": {
"type": "boolean",
"description": "True when the number is assigned, or any assigned organization matches before paging."
},
"shown": {
"type": "number",
"description": "Results returned."
},
"notice": {
"type": "string",
"description": "Guidance on a miss, a cut list, or another condition."
},
"source": {
"type": "object",
"required": [
"registry_id",
"url",
"fetched_at",
"stale"
],
"properties": {
"url": {
"type": "string",
"description": "The file fetched from iana.org."
},
"stale": {
"type": "boolean",
"description": "True when a refresh failed and a cached copy up to 7 days old answered."
},
"fetched_at": {
"type": "string",
"description": "ISO 8601 time of the last successful fetch or revalidation."
},
"registry_id": {
"type": "string",
"description": "Id of the registry file that answered."
},
"registry_updated": {
"type": "string",
"description": "The registry's own last-updated date; absent for the protocol index."
}
},
"description": "Provenance and freshness of the answer.",
"additionalProperties": false
},
"sub_arcs": {
"type": "string",
"description": "Arcs below the enterprise number, e.g. \"1.2\"; the enterprise assigns these."
},
"truncated": {
"type": "boolean",
"description": "True when more matches exist than were returned."
},
"totalCount": {
"type": "number",
"description": "Matches before the limit was applied."
},
"enterprises": {
"type": "array",
"items": {
"type": "object",
"required": [
"number",
"oid",
"state"
],
"properties": {
"oid": {
"type": "string",
"description": "The enterprise OID prefix, e.g. \"1.3.6.1.4.1.32473\"."
},
"state": {
"enum": [
"assigned",
"reserved",
"unassigned"
],
"type": "string",
"description": "reserved (\"Reserved\"), unassigned (\"Unassigned\" or \"---none---\"), matched as whole markers case-insensitively; else assigned."
},
"number": {
"type": "number",
"description": "The Private Enterprise Number."
},
"organization": {
"type": "string",
"description": "Organization line; absent when withheld or missing."
},
"organization_withheld": {
"type": "boolean",
"description": "True when the line mixes in contact details and is withheld."
}
},
"description": "One enterprise number entry.",
"additionalProperties": false
},
"description": "Matching entries: exact organization-name hits first, then number order."
},
"next_offset": {
"type": "number",
"description": "Pass as offset for the next page; absent on the last."
},
"requested_oid": {
"type": "string",
"description": "The OID as requested, when it named arcs below the enterprise number."
},
"effective_limit": {
"type": "number",
"description": "The response limit after clamping, present when clamped."
},
"requested_limit": {
"type": "number",
"description": "The requested limit, present when clamped."
}
},
"additionalProperties": false
}iana_lookup_pen annotations
{
"readOnlyHint": true,
"openWorldHint": true,
"idempotentHint": true
}iana_lookup_language_tag — Validate a BCP 47 language tag
Advertised read-onlyOpen-world
Parse and validate a BCP 47 language tag against the IANA Language Subtag Registry, or search subtags by description. Pass exactly one of `tag` (e.g. "zh-Hant-TW", "sr-Latn", "en_US") or `description` (e.g. "Swiss German"). A tag is split into language, extlang, script, region, variant, extension, and private-use parts; deprecated subtags report their preferred value, and a canonical tag is returned when valid. Extension singleton allocation and defining RFCs are optional metadata; allocation never validates extension content or changes base validity. A single subtag registered under several types (e.g. "TW") lists the other types.
iana_lookup_language_tag input schema
{
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"tag": {
"type": "string",
"pattern": "^[A-Za-z0-9]{1,8}(?:-[A-Za-z0-9]{1,8})*$",
"maxLength": 100,
"description": "A language tag to validate, e.g. \"zh-Hant-TW\", \"sr-Latn\", \"i-klingon\". Underscores are read as hyphens (\"en_US\" → \"en-US\"); matching ignores case. Pass this or description, not both."
},
"limit": {
"type": "integer",
"default": 25,
"maximum": 1000000,
"minimum": 1,
"description": "Requested description matches, 1–1,000,000, clamped to 100 with requested_limit and effective_limit disclosed. Default 25. Tag mode always returns every part of the tag."
},
"offset": {
"type": "integer",
"default": 0,
"maximum": 9007199254740991,
"minimum": 0,
"description": "Number of description matches to skip; pass the next_offset of the previous response to get the next page. Default 0."
},
"description": {
"type": "string",
"maxLength": 100,
"minLength": 2,
"description": "Words matched as whole tokens against subtag descriptions, e.g. \"Swiss German\" or \"Cyrillic\". Pass this or tag, not both."
},
"subtag_type": {
"enum": [
"language",
"extlang",
"script",
"region",
"variant",
"grandfathered",
"redundant"
],
"type": "string",
"description": "Description mode only: return only records of this Type."
}
},
"additionalProperties": false
}iana_lookup_language_tag output schema
{
"type": "object",
"anyOf": [
{
"not": {
"required": [
"error"
]
},
"required": [
"mode",
"source",
"totalCount",
"shown",
"cap",
"truncated"
]
},
{
"required": [
"error"
]
}
],
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"cap": {
"type": "number",
"description": "The limit applied."
},
"mode": {
"enum": [
"tag",
"description"
],
"type": "string",
"description": "Which lookup ran."
},
"error": {
"type": "object",
"required": [
"code",
"message"
],
"properties": {
"code": {
"type": "integer",
"maximum": 9007199254740991,
"minimum": -9007199254740991,
"description": "JSON-RPC error code for this failure."
},
"data": {
"type": "object",
"properties": {
"reason": {
"type": "string",
"examples": [
"mode_required",
"upstream_unreadable",
"pacer_shed"
],
"description": "Machine-readable failure mode. Declared by this tool: `mode_required`: Neither or both of tag and description were given. `upstream_unreadable`: The language subtag registry could not be fetched or parsed to zero records. `pacer_shed`: This server's own iana.org request queue is too full for the call to start in time. Other values are possible when a failure originates below the handler."
},
"recovery": {
"type": "object",
"required": [
"hint"
],
"properties": {
"hint": {
"type": "string"
}
},
"description": "Actionable next step for the caller.",
"additionalProperties": {}
},
"retryable": {
"type": "boolean",
"description": "Whether retrying may succeed."
}
},
"additionalProperties": {}
},
"message": {
"type": "string",
"description": "Human-readable description of what went wrong."
}
},
"description": "Present when the call failed. Absent on success.",
"additionalProperties": {}
},
"shown": {
"type": "number",
"description": "Results returned."
},
"valid": {
"type": "boolean",
"description": "Tag mode: true when well-formed, every subtag is registered and correctly placed, and no variant or singleton repeats."
},
"issues": {
"type": "array",
"items": {
"type": "object",
"required": [
"subtag",
"kind",
"message"
],
"properties": {
"kind": {
"enum": [
"unknown",
"deprecated",
"wrong_position",
"variant_prefix_mismatch",
"suppress_script_redundant",
"extension_not_validated"
],
"type": "string",
"description": "unknown (not registered for its position) and wrong_position (misplaced, repeated, or an extlang after the wrong language) make the tag invalid; the rest are advisory."
},
"subtag": {
"type": "string",
"description": "The subtag or sequence the issue is about."
},
"message": {
"type": "string",
"description": "What is wrong and what to use instead."
}
},
"description": "One finding about the tag.",
"additionalProperties": false
},
"description": "Tag mode: findings; empty for a clean tag."
},
"notice": {
"type": "string",
"description": "Guidance on a miss, a cut list, or another condition."
},
"source": {
"type": "object",
"required": [
"registry_id",
"url",
"fetched_at",
"stale"
],
"properties": {
"url": {
"type": "string",
"description": "The file fetched from iana.org."
},
"stale": {
"type": "boolean",
"description": "True when a refresh failed and a cached copy up to 7 days old answered."
},
"fetched_at": {
"type": "string",
"description": "ISO 8601 time of the last successful fetch or revalidation."
},
"registry_id": {
"type": "string",
"description": "Id of the registry file that answered."
},
"registry_updated": {
"type": "string",
"description": "The registry's own last-updated date; absent for the protocol index."
}
},
"description": "Provenance and freshness of the answer.",
"additionalProperties": false
},
"matches": {
"type": "array",
"items": {
"type": "object",
"required": [
"type",
"subtag",
"descriptions"
],
"properties": {
"type": {
"enum": [
"language",
"extlang",
"script",
"region",
"variant",
"grandfathered",
"redundant"
],
"type": "string",
"description": "The record Type."
},
"added": {
"type": "string",
"description": "Date added, YYYY-MM-DD."
},
"scope": {
"type": "string",
"description": "macrolanguage, collection, special, or private-use."
},
"subtag": {
"type": "string",
"description": "Subtag; the whole tag for grandfathered/redundant; a range such as \"qaa..qtz\"."
},
"comments": {
"type": "array",
"items": {
"type": "string"
},
"description": "Comments values."
},
"prefixes": {
"type": "array",
"items": {
"type": "string"
},
"description": "Prefix values: the tags this extlang or variant follows."
},
"deprecated": {
"type": "string",
"description": "Date deprecated, YYYY-MM-DD; still valid, but prefer preferred_value."
},
"descriptions": {
"type": "array",
"items": {
"type": "string"
},
"description": "Description values; empty when unregistered."
},
"macrolanguage": {
"type": "string",
"description": "Encompassing macrolanguage, e.g. \"zh\"."
},
"preferred_value": {
"type": "string",
"description": "The subtag or tag to use instead."
},
"suppress_script": {
"type": "string",
"description": "Script subtag this language normally omits, e.g. \"Latn\"."
}
},
"description": "One registry record.",
"additionalProperties": false
},
"description": "Description mode: matching records, exact description matches first, then registry order."
},
"subtags": {
"type": "array",
"items": {
"type": "object",
"required": [
"subtag",
"position",
"registered",
"descriptions"
],
"properties": {
"added": {
"type": "string",
"description": "Date added, YYYY-MM-DD."
},
"scope": {
"type": "string",
"description": "macrolanguage, collection, special, or private-use."
},
"subtag": {
"type": "string",
"description": "Subtag in canonical case; the whole sequence of an extension or private-use part; the whole tag for grandfathered/redundant."
},
"comments": {
"type": "array",
"items": {
"type": "string"
},
"description": "Comments values."
},
"position": {
"enum": [
"language",
"extlang",
"script",
"region",
"variant",
"extension",
"privateuse",
"grandfathered",
"redundant"
],
"type": "string",
"description": "Position in the tag; grandfathered/redundant for a whole-tag record."
},
"prefixes": {
"type": "array",
"items": {
"type": "string"
},
"description": "Prefix values: the tags this extlang or variant follows."
},
"extension": {
"type": "object",
"required": [
"singleton",
"allocation",
"descriptions",
"references",
"guidance"
],
"properties": {
"guidance": {
"type": "string",
"description": "How to interpret allocation and validate extension content, or retry unavailable metadata."
},
"authority": {
"type": "string",
"description": "The registry authority organization; no contacts."
},
"singleton": {
"type": "string",
"description": "The extension singleton, e.g. u or t."
},
"allocation": {
"enum": [
"allocated",
"unallocated",
"unavailable"
],
"type": "string",
"description": "Singleton allocation only; never validation of extension content."
},
"references": {
"type": "array",
"items": {
"type": "object",
"required": [
"type",
"id"
],
"properties": {
"id": {
"type": "string",
"description": "E.g. \"RFC 9110\", a draft name, a registry id, or a URL."
},
"url": {
"type": "string",
"description": "URL of the reference."
},
"type": {
"enum": [
"rfc",
"draft",
"uri",
"registry",
"rfc-errata",
"note",
"text"
],
"type": "string",
"description": "Reference kind."
},
"label": {
"type": "string",
"description": "Label text, when it adds to id and section."
},
"section": {
"type": "string",
"description": "Section, e.g. \"15.5.5\"."
}
},
"description": "A defining reference.",
"additionalProperties": false
},
"description": "Defining RFCs, empty when allocation is unknown or unallocated."
},
"descriptions": {
"type": "array",
"items": {
"type": "string"
},
"description": "Allocated extension descriptions, empty otherwise."
}
},
"description": "Optional extension allocation metadata, independent of base tag validity.",
"additionalProperties": false
},
"deprecated": {
"type": "string",
"description": "Date deprecated, YYYY-MM-DD; still valid, but prefer preferred_value."
},
"registered": {
"type": "boolean",
"description": "True when a record covers the subtag at this position (private-use ranges count); always false for extension and private-use parts."
},
"descriptions": {
"type": "array",
"items": {
"type": "string"
},
"description": "Description values; empty when unregistered."
},
"macrolanguage": {
"type": "string",
"description": "Encompassing macrolanguage, e.g. \"zh\"."
},
"preferred_value": {
"type": "string",
"description": "The subtag or tag to use instead."
},
"suppress_script": {
"type": "string",
"description": "Script subtag this language normally omits, e.g. \"Latn\"."
}
},
"description": "One part of the tag.",
"additionalProperties": false
},
"description": "Tag mode: the parts in order, after any whole-tag record; parsing stops at the first part the syntax cannot place."
},
"tag_input": {
"type": "string",
"description": "Tag mode: the tag as read, after underscores became hyphens."
},
"truncated": {
"type": "boolean",
"description": "True when more matches exist than were returned."
},
"totalCount": {
"type": "number",
"description": "Matches before the limit was applied."
},
"next_offset": {
"type": "number",
"description": "Pass as offset for the next page; absent on the last."
},
"well_formed": {
"type": "boolean",
"description": "Tag mode: true when the tag follows RFC 5646 syntax or is grandfathered."
},
"canonical_tag": {
"type": "string",
"description": "Tag mode, valid tags only: canonical form (preferred values applied, variant collisions deduplicated, registered heploc context normalized, extlang reduced, case normalized)."
},
"effective_limit": {
"type": "number",
"description": "The response limit after clamping, present when clamped."
},
"requested_limit": {
"type": "number",
"description": "The requested limit, present when clamped."
},
"extension_source": {
"type": "object",
"required": [
"registry_id",
"url",
"fetched_at",
"stale"
],
"properties": {
"url": {
"type": "string",
"description": "The file fetched from iana.org."
},
"stale": {
"type": "boolean",
"description": "True when a refresh failed and a cached copy up to 7 days old answered."
},
"fetched_at": {
"type": "string",
"description": "ISO 8601 time of the last successful fetch or revalidation."
},
"registry_id": {
"type": "string",
"description": "Id of the registry file that answered."
},
"registry_updated": {
"type": "string",
"description": "The registry's own last-updated date; absent for the protocol index."
}
},
"description": "Provenance of the allocation registry copy; absent when unavailable or no extensions were read.",
"additionalProperties": false
},
"also_registered_as": {
"type": "array",
"items": {
"type": "object",
"required": [
"type",
"subtag",
"descriptions"
],
"properties": {
"type": {
"enum": [
"language",
"extlang",
"script",
"region",
"variant",
"grandfathered",
"redundant"
],
"type": "string",
"description": "The record Type."
},
"added": {
"type": "string",
"description": "Date added, YYYY-MM-DD."
},
"scope": {
"type": "string",
"description": "macrolanguage, collection, special, or private-use."
},
"subtag": {
"type": "string",
"description": "Subtag; the whole tag for grandfathered/redundant; a range such as \"qaa..qtz\"."
},
"comments": {
"type": "array",
"items": {
"type": "string"
},
"description": "Comments values."
},
"prefixes": {
"type": "array",
"items": {
"type": "string"
},
"description": "Prefix values: the tags this extlang or variant follows."
},
"deprecated": {
"type": "string",
"description": "Date deprecated, YYYY-MM-DD; still valid, but prefer preferred_value."
},
"descriptions": {
"type": "array",
"items": {
"type": "string"
},
"description": "Description values; empty when unregistered."
},
"macrolanguage": {
"type": "string",
"description": "Encompassing macrolanguage, e.g. \"zh\"."
},
"preferred_value": {
"type": "string",
"description": "The subtag or tag to use instead."
},
"suppress_script": {
"type": "string",
"description": "Script subtag this language normally omits, e.g. \"Latn\"."
}
},
"description": "One registry record.",
"additionalProperties": false
},
"description": "Tag mode, single-subtag input: records of other types under the same subtag, e.g. region \"TW\" beside language \"tw\"."
}
},
"additionalProperties": false
}iana_lookup_language_tag annotations
{
"readOnlyHint": true,
"openWorldHint": true,
"idempotentHint": true
}iana_get_rfc_status — Get RFC, Internet-Draft, and series status
Advertised read-onlyOpen-world
Get the current status of up to ten distinct RFCs, Internet-Drafts, or BCP/STD/FYI series per page from up to 1,000 input items. Canonical aliases resolve once. When more remain, deferred_ids previews the next ten, deferred_count counts the whole remainder, and next_ids_offset continues the same original ids. Retry failed ids separately. Accepts "RFC 9110", "rfc9110", "9110", draft names with or without a revision suffix ("draft-ietf-httpbis-semantics-19"), series numbers ("BCP 14"), RFC and draft file names ("rfc9110.txt"), the URL of an RFC or draft on datatracker.ietf.org, tools.ietf.org, or ietf.org or of an RFC on rfc-editor.org, and a series URL at rfc-editor.org/info/ or datatracker.ietf.org/doc/ ("https://datatracker.ietf.org/doc/bcp14/"). RFCs return current and as-published status, stream, working group, obsoletes/obsoleted-by and updates/updated-by relations, the series they belong to, and the errata page; drafts return their state, IESG state, intended status, expiry, the document that replaced them, and the RFC they became; a series returns its member RFCs. Unknown ids return found: false. A call makes at most 20 Datatracker requests, retries included (an RFC or a series needs one, plus one per call for the RFCs' series; a draft three, or four with a revision suffix): each id is taken in request order if its requests still fit, and the others come back in failed with reason request_limit, to pass in another call.
iana_get_rfc_status input schema
{
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"ids"
],
"properties": {
"ids": {
"type": "array",
"items": {
"type": "string",
"maxLength": 200,
"description": "One RFC number (\"RFC 9110\", \"9110\"), draft name (also I-D.<name>), series number (\"BCP 14\"), RFC or draft file name, RFC DOI (bare, doi:, or https://doi.org/), RFC Editor errata URL, or a URL of a form the tool description lists. Balanced citation brackets and a trailing \", Section 15.5.5\" are accepted; sections are ignored with a notice because only document status is returned. A URL's query and fragment are dropped before this 200-character limit applies."
},
"maxItems": 1000,
"minItems": 1,
"description": "Up to 1,000 normalized nonblank RFC, Internet-Draft, or series items; aliases are canonically deduplicated before selecting ten distinct ids. One comma-, semicolon-, or newline-separated string is also accepted. Resubmit the same ids with next_ids_offset as ids_offset to continue."
},
"ids_offset": {
"type": "integer",
"default": 0,
"maximum": 9007199254740991,
"minimum": 0,
"description": "Number of canonically distinct ids to skip, default 0. Pass next_ids_offset with the same original ids to continue; retry failed ids separately."
}
},
"additionalProperties": false
}iana_get_rfc_status output schema
{
"type": "object",
"anyOf": [
{
"not": {
"required": [
"error"
]
},
"required": [
"total_ids",
"deferred_ids",
"deferred_count",
"documents",
"failed"
]
},
{
"required": [
"error"
]
}
],
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"error": {
"type": "object",
"required": [
"code",
"message"
],
"properties": {
"code": {
"type": "integer",
"maximum": 9007199254740991,
"minimum": -9007199254740991,
"description": "JSON-RPC error code for this failure."
},
"data": {
"type": "object",
"properties": {
"reason": {
"type": "string",
"examples": [
"upstream_unreadable",
"pacer_shed",
"request_limit"
],
"description": "Machine-readable failure mode. Declared by this tool: `upstream_unreadable`: Every id failed because the RFC Editor or Datatracker sent a response that could not be read. `pacer_shed`: This server's own RFC Editor or Datatracker request queue is too full for any id to start in time. `request_limit`: An id did not fit within the call's limit of 20 Datatracker requests, a third of this server's per-minute Datatracker pacing, or retries used up the limit before it resolved. Those ids land in failed with this reason; the call itself fails with it only when no id resolved. Other values are possible when a failure originates below the handler."
},
"recovery": {
"type": "object",
"required": [
"hint"
],
"properties": {
"hint": {
"type": "string"
}
},
"description": "Actionable next step for the caller.",
"additionalProperties": {}
},
"retryable": {
"type": "boolean",
"description": "Whether retrying may succeed."
}
},
"additionalProperties": {}
},
"message": {
"type": "string",
"description": "Human-readable description of what went wrong."
}
},
"description": "Present when the call failed. Absent on success.",
"additionalProperties": {}
},
"failed": {
"type": "array",
"items": {
"type": "object",
"required": [
"id",
"error"
],
"properties": {
"id": {
"type": "string",
"description": "The document whose lookup failed."
},
"error": {
"type": "string",
"description": "What failed."
},
"reason": {
"type": "string",
"description": "Failure reason, when classified: \"request_limit\" (call again with this id now), or an upstream one such as \"upstream_unreadable\"."
},
"retryable": {
"type": "boolean",
"description": "Whether calling again with this id can succeed, when the failure states it: true for request_limit; false when the outcome repeats, such as an upstream redirect this server does not follow."
}
},
"description": "One failed id.",
"additionalProperties": false
},
"description": "Ids whose lookup failed upstream or was cut by the call's request limit; the rest of the batch still answered."
},
"notice": {
"type": "string",
"description": "Set when selected document citations carried ignored section qualifiers, ids were left unresolved at the call's Datatracker request limit, or Datatracker fields (stream and group, or series membership) were unavailable for some RFCs."
},
"documents": {
"type": "array",
"items": {
"type": "object",
"required": [
"id",
"kind",
"found"
],
"properties": {
"id": {
"type": "string",
"description": "As resolved: \"RFC 9110\", \"BCP 14\", or a draft name without revision; the id as given (a URL without its query or fragment) when unsupported, and the draft name as requested when no draft was found."
},
"rfc": {
"type": "object",
"required": [
"status",
"published_status",
"published",
"authors",
"obsoletes",
"obsoleted_by",
"updates",
"updated_by",
"doi",
"url",
"datatracker_url"
],
"properties": {
"doi": {
"type": "string",
"description": "DOI, e.g. \"10.17487/RFC9110\"."
},
"url": {
"type": "string",
"description": "The RFC on the RFC Editor site."
},
"group": {
"type": "object",
"required": [
"acronym",
"name",
"type"
],
"properties": {
"name": {
"type": "string",
"description": "Group name."
},
"type": {
"type": "string",
"description": "E.g. \"WG\", \"RG\", \"Individual\"."
},
"acronym": {
"type": "string",
"description": "E.g. \"httpbis\"; \"none\" for individual submissions."
}
},
"description": "The responsible Datatracker group.",
"additionalProperties": false
},
"status": {
"type": "string",
"description": "Current status per the RFC Editor, e.g. \"INTERNET STANDARD\", \"HISTORIC\"."
},
"stream": {
"type": "string",
"description": "Stream, e.g. \"IETF\", \"IRTF\", \"IAB\", \"ISE\"."
},
"authors": {
"type": "array",
"items": {
"type": "string"
},
"description": "Authors as published."
},
"is_also": {
"type": "array",
"items": {
"type": "string"
},
"description": "The BCP, STD, or FYI series it belongs to, e.g. \"BCP 14\"; empty when it is in none. Absent when series membership could not be read (see notice)."
},
"updates": {
"type": "array",
"items": {
"type": "string"
},
"description": "RFCs this RFC updates."
},
"obsoletes": {
"type": "array",
"items": {
"type": "string"
},
"description": "RFCs this RFC obsoletes, e.g. \"RFC 7230\"."
},
"published": {
"type": "string",
"description": "Publication month and year, e.g. \"June 2022\"."
},
"draft_name": {
"type": "string",
"description": "The Internet-Draft it was published from."
},
"errata_url": {
"type": "string",
"description": "Errata page, when errata exist."
},
"page_count": {
"type": "number",
"description": "Page count."
},
"updated_by": {
"type": "array",
"items": {
"type": "string"
},
"description": "RFCs that update this RFC."
},
"obsoleted_by": {
"type": "array",
"items": {
"type": "string"
},
"description": "RFCs that obsolete this RFC."
},
"datatracker_url": {
"type": "string",
"description": "The RFC on the IETF Datatracker."
},
"published_status": {
"type": "string",
"description": "Status at publication, which may since have changed."
}
},
"description": "Present when kind is rfc and found is true.",
"additionalProperties": false
},
"kind": {
"enum": [
"rfc",
"draft",
"series",
"unsupported"
],
"type": "string",
"description": "How the id was read: an RFC, an Internet-Draft, a BCP/STD/FYI series, or unsupported text."
},
"draft": {
"type": "object",
"required": [
"rev",
"state",
"last_updated",
"replaced_by",
"replaces",
"datatracker_url"
],
"properties": {
"rev": {
"type": "string",
"description": "Latest revision, e.g. \"19\"."
},
"group": {
"type": "object",
"required": [
"acronym",
"name",
"type"
],
"properties": {
"name": {
"type": "string",
"description": "Group name."
},
"type": {
"type": "string",
"description": "E.g. \"WG\", \"RG\", \"Individual\"."
},
"acronym": {
"type": "string",
"description": "E.g. \"httpbis\"; \"none\" for individual submissions."
}
},
"description": "The responsible Datatracker group.",
"additionalProperties": false
},
"state": {
"type": "string",
"description": "E.g. \"Active\", \"Expired\", \"Replaced\", \"RFC\"."
},
"stream": {
"type": "string",
"description": "Stream, e.g. \"IETF\"."
},
"expires": {
"type": "string",
"description": "Expiry time of the latest revision."
},
"replaces": {
"type": "array",
"items": {
"type": "string"
},
"description": "Documents this draft replaced."
},
"became_rfc": {
"type": "string",
"description": "The RFC it became, e.g. \"RFC 9110\"."
},
"iesg_state": {
"type": "string",
"description": "IESG state, e.g. \"RFC Published\"."
},
"replaced_by": {
"type": "array",
"items": {
"type": "string"
},
"description": "Documents that replaced this draft."
},
"last_updated": {
"type": "string",
"description": "Last-updated time, \"YYYY-MM-DD HH:MM:SS\"."
},
"datatracker_url": {
"type": "string",
"description": "The draft on the IETF Datatracker."
},
"rfceditor_state": {
"type": "string",
"description": "RFC Editor queue state, when in the queue."
},
"intended_std_level": {
"type": "string",
"description": "Intended status, e.g. \"Proposed Standard\"."
},
"requested_revision": {
"type": "string",
"description": "The revision suffix requested, when the draft was found without it."
}
},
"description": "Present when kind is draft and found is true.",
"additionalProperties": false
},
"found": {
"type": "boolean",
"description": "True when the document exists upstream, or the series has member RFCs."
},
"title": {
"type": "string",
"description": "Document title."
},
"series": {
"type": "object",
"required": [
"members",
"datatracker_url"
],
"properties": {
"members": {
"type": "array",
"items": {
"type": "string"
},
"description": "Member RFCs in ascending order, e.g. \"RFC 2119\"."
},
"datatracker_url": {
"type": "string",
"description": "The series on the IETF Datatracker."
}
},
"description": "Present when kind is series and found is true.",
"additionalProperties": false
},
"guidance": {
"type": "string",
"description": "Why nothing was found and what to pass instead; on a found draft, that the requested revision does not exist."
}
},
"description": "One requested document.",
"additionalProperties": false
},
"description": "One entry per distinct requested id, in request order, excluding ids in failed."
},
"total_ids": {
"type": "number",
"description": "Total canonically distinct ids before ids_offset and the ten-id batch limit."
},
"deferred_ids": {
"type": "array",
"items": {
"type": "string",
"description": "One canonical id."
},
"description": "Preview of the next at most ten canonical ids, not the entire remainder; no upstream work started for these ids."
},
"deferred_count": {
"type": "number",
"description": "All distinct ids remaining after this selected batch, including ids beyond the preview."
},
"deferred_reason": {
"type": "string",
"const": "batch_limit",
"description": "More distinct ids remain beyond the ten-id batch limit."
},
"next_ids_offset": {
"type": "number",
"description": "Pass as ids_offset with the same original ids to resolve the next batch; absent at or past the end."
},
"deferred_guidance": {
"type": "string",
"description": "How to continue the original id list and retry selected failed ids separately."
}
},
"additionalProperties": false
}iana_get_rfc_status annotations
{
"readOnlyHint": true,
"openWorldHint": true,
"idempotentHint": true
}iana_search_registries — Search IANA registries
Advertised read-onlyOpen-world
Find IANA protocol registries and sub-registries by keyword over their titles and protocol categories, e.g. "tls cipher", "dns resource record", "protocol numbers". Returns the registry and sub-registry ids that iana_get_registry_records reads, with registration procedure and defining documents. Covers every registry linked from the IANA protocol registries index.
iana_search_registries input schema
{
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"query"
],
"properties": {
"limit": {
"type": "integer",
"default": 15,
"maximum": 1000000,
"minimum": 1,
"description": "Requested maximum results, 1–1,000,000; values above 50 are clamped to 50 and disclosed as requested_limit and effective_limit. Default 15."
},
"query": {
"type": "string",
"maxLength": 100,
"minLength": 2,
"description": "Words matched as whole tokens, singular or plural, against registry titles, categories, and ids, e.g. \"tls cipher\". An exact registry or sub-registry id ranks first, then the closest titles."
},
"offset": {
"type": "integer",
"default": 0,
"maximum": 9007199254740991,
"minimum": 0,
"description": "Number of matches to skip; pass the next_offset of the previous response to get the next page. Default 0."
}
},
"additionalProperties": false
}iana_search_registries output schema
{
"type": "object",
"anyOf": [
{
"not": {
"required": [
"error"
]
},
"required": [
"registries",
"source",
"totalCount",
"shown",
"cap",
"truncated"
]
},
{
"required": [
"error"
]
}
],
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"cap": {
"type": "number",
"description": "The limit applied."
},
"error": {
"type": "object",
"required": [
"code",
"message"
],
"properties": {
"code": {
"type": "integer",
"maximum": 9007199254740991,
"minimum": -9007199254740991,
"description": "JSON-RPC error code for this failure."
},
"data": {
"type": "object",
"properties": {
"reason": {
"type": "string",
"examples": [
"index_unreadable",
"pacer_shed"
],
"description": "Machine-readable failure mode. Declared by this tool: `index_unreadable`: The IANA protocol index page could not be read, or it listed far fewer registries than a complete index holds, and no good copy up to 7 days old is cached. `pacer_shed`: This server's own iana.org request queue is too full for the call to start in time. Other values are possible when a failure originates below the handler."
},
"recovery": {
"type": "object",
"required": [
"hint"
],
"properties": {
"hint": {
"type": "string"
}
},
"description": "Actionable next step for the caller.",
"additionalProperties": {}
},
"retryable": {
"type": "boolean",
"description": "Whether retrying may succeed."
}
},
"additionalProperties": {}
},
"message": {
"type": "string",
"description": "Human-readable description of what went wrong."
}
},
"description": "Present when the call failed. Absent on success.",
"additionalProperties": {}
},
"shown": {
"type": "number",
"description": "Results returned."
},
"notice": {
"type": "string",
"description": "Guidance on a miss, a cut list, or another condition."
},
"source": {
"type": "object",
"required": [
"registry_id",
"url",
"fetched_at",
"stale"
],
"properties": {
"url": {
"type": "string",
"description": "The file fetched from iana.org."
},
"stale": {
"type": "boolean",
"description": "True when a refresh failed and a cached copy up to 7 days old answered."
},
"fetched_at": {
"type": "string",
"description": "ISO 8601 time of the last successful fetch or revalidation."
},
"registry_id": {
"type": "string",
"description": "Id of the registry file that answered."
},
"registry_updated": {
"type": "string",
"description": "The registry's own last-updated date; absent for the protocol index."
}
},
"description": "Provenance and freshness of the answer.",
"additionalProperties": false
},
"truncated": {
"type": "boolean",
"description": "True when more matches exist than were returned."
},
"registries": {
"type": "array",
"items": {
"type": "object",
"required": [
"registry_id",
"title",
"category",
"defining_documents",
"page_url",
"xml_url"
],
"properties": {
"title": {
"type": "string",
"description": "Registry or sub-registry title."
},
"xml_url": {
"type": "string",
"description": "The registry XML file."
},
"category": {
"type": "string",
"description": "Protocol category in the index; an entry listed under several joins them with \"; \"."
},
"page_url": {
"type": "string",
"description": "The registry page on iana.org."
},
"registry_id": {
"type": "string",
"description": "Pass as registry to iana_get_registry_records."
},
"subregistry_id": {
"type": "string",
"description": "Pass as subregistry to iana_get_registry_records."
},
"defining_documents": {
"type": "array",
"items": {
"type": "object",
"required": [
"id"
],
"properties": {
"id": {
"type": "string",
"description": "Document id, e.g. \"RFC8446\"."
},
"url": {
"type": "string",
"description": "Link via iana.org."
},
"title": {
"type": "string",
"description": "Document title."
}
},
"description": "A defining document.",
"additionalProperties": false
},
"description": "Documents that define the registry."
},
"registration_procedure": {
"type": "string",
"description": "Registration procedure, e.g. \"IETF Review\"."
}
},
"description": "One index entry.",
"additionalProperties": false
},
"description": "Matching index entries: exact id hits first, then the closest titles."
},
"totalCount": {
"type": "number",
"description": "Matches before the limit was applied."
},
"next_offset": {
"type": "number",
"description": "Pass as offset for the next page; absent on the last."
},
"effective_limit": {
"type": "number",
"description": "The response limit after clamping, present when clamped."
},
"requested_limit": {
"type": "number",
"description": "The requested limit, present when clamped."
}
},
"additionalProperties": false
}iana_search_registries annotations
{
"readOnlyHint": true,
"openWorldHint": true,
"idempotentHint": true
}iana_get_registry_records — Read IANA registry records
Advertised read-onlyOpen-world
Read records from any IANA XML registry by id, e.g. registry "tls-parameters" with subregistry "tls-parameters-4" (TLS Cipher Suites), "protocol-numbers", "http-methods", or "cbor-tags"; an iana.org/assignments URL also works. Filter with `value` on the key column or the column `field` names: signed decimal points match exact cells, inclusive ranges and strict open bounds; scalar 0x points also compare with decimal cells and established bare-hex columns. Two-byte 0x points match byte-pair ranges and wildcards with their width preserved. An implicit range-only key match yields a miss and a field pointer when another column holds the value exactly. Filter with `contains` for words in any field; records with an equal field come first. When a registry has several sub-registries and none is given, the response lists them instead of records; a table that nests tables lists them too. Field names are the registry's XML element names (e.g. "rec" is the Recommended column). Large registries page through `cursor`. Find ids with iana_search_registries.
iana_get_registry_records input schema
{
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"registry"
],
"properties": {
"field": {
"type": "string",
"maxLength": 100,
"description": "Column for value to match instead of the key column, case-insensitive, one of the names in columns: e.g. \"type\" for a DNS RR type mnemonic, or \"name\" for every row of a service name. Ignored without value."
},
"limit": {
"type": "integer",
"default": 25,
"maximum": 1000000,
"minimum": 1,
"description": "Requested maximum results, 1–1,000,000; values above 100 are clamped to 100 and disclosed as requested_limit and effective_limit. Default 25."
},
"value": {
"type": "string",
"maxLength": 100,
"description": "Match the key column named by value_field (value, else number, else first column), or field when set; case and whitespace are ignored. Signed decimal points compare without precision loss with exact integers, inclusive a-b or a to b ranges, and strict less than / greater than bounds. Decimal input never gains hexadecimal meaning. One 0x token also compares numerically with decimal cells and ranges; bare hex is recognized only in ieee-802-numbers-1/type_hex and ppp-numbers-2/value. Hex byte forms keep their written width: 0x1301, {0x13,0x01}, and 0x13 0x01 find 0x13,0x01; 0x0013 finds 0x00,0x13 but 0x13 does not. Two-byte points also match 0xHH,0xLL-MM, 0xHH,* and 0xAA-BB,* rows. Scalar hex ranges such as 0x11-0xff and literal range equality remain supported. An implicit range-only match with an exact alternate-column hit returns a miss naming field; explicit field selection is authoritative."
},
"cursor": {
"type": "string",
"maxLength": 1000,
"description": "next_cursor from the previous page; reuse it only with the same registry, subregistry, value, field, and contains."
},
"contains": {
"type": "string",
"maxLength": 100,
"minLength": 2,
"description": "Words matched as whole tokens against every field and reference id, e.g. \"chacha20\". Records with a field equal to the words come first."
},
"registry": {
"type": "string",
"pattern": "^(?:[A-Za-z0-9_][A-Za-z0-9_.-]{0,63}|https?:\\/\\/(?:www\\.)?iana\\.org\\/assignments\\/[A-Za-z0-9_][A-Za-z0-9_.-]{0,63}(?:\\/[^\\s#]*)?(?:#[A-Za-z0-9_][A-Za-z0-9_.-]{0,99})?)$",
"maxLength": 200,
"description": "Registry id, e.g. \"tls-parameters\", or its https://www.iana.org/assignments/<id> URL (a #fragment selects the sub-registry when subregistry is unset)."
},
"subregistry": {
"type": "string",
"pattern": "^[A-Za-z0-9_][A-Za-z0-9_.-]{0,99}$",
"description": "Sub-registry id, case-insensitive, e.g. \"tls-parameters-4\". Omit to read the only sub-registry, or to list them when there are several."
}
},
"additionalProperties": false
}iana_get_registry_records output schema
{
"type": "object",
"anyOf": [
{
"not": {
"required": [
"error"
]
},
"required": [
"registry_id",
"registry_title",
"notes",
"columns",
"records",
"source",
"totalCount",
"shown",
"cap",
"truncated"
]
},
{
"required": [
"error"
]
}
],
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"cap": {
"type": "number",
"description": "The limit applied."
},
"error": {
"type": "object",
"required": [
"code",
"message"
],
"properties": {
"code": {
"type": "integer",
"maximum": 9007199254740991,
"minimum": -9007199254740991,
"description": "JSON-RPC error code for this failure."
},
"data": {
"type": "object",
"properties": {
"reason": {
"type": "string",
"examples": [
"unknown_registry",
"unknown_subregistry",
"unknown_field",
"non_xml_registry",
"invalid_cursor",
"cursor_mismatch",
"upstream_unreadable",
"pacer_shed"
],
"description": "Machine-readable failure mode. Declared by this tool: `unknown_registry`: The registry XML returns 404 and no case-insensitive index match exists, or the index is unavailable. `unknown_subregistry`: The subregistry id is not in this registry. `unknown_field`: The field, given with value, is not a column of the table read. `non_xml_registry`: The registry, or the sub-registry read, holds no XML records and points at a file published separately, such as plain text or a MIB module. `invalid_cursor`: The cursor is not one this tool returned: malformed, corrupted, or carrying an offset or limit that is not a whole number of zero or more. `cursor_mismatch`: The cursor was minted for a different registry, subregistry, value, field, or contains. `upstream_unreadable`: The registry XML could not be read, was not XML, or was larger than this server accepts. `pacer_shed`: This server's own iana.org request queue is too full for the call to start in time. Other values are possible when a failure originates below the handler."
},
"recovery": {
"type": "object",
"required": [
"hint"
],
"properties": {
"hint": {
"type": "string"
}
},
"description": "Actionable next step for the caller.",
"additionalProperties": {}
},
"retryable": {
"type": "boolean",
"description": "Whether retrying may succeed."
}
},
"additionalProperties": {}
},
"message": {
"type": "string",
"description": "Human-readable description of what went wrong."
}
},
"description": "Present when the call failed. Absent on success.",
"additionalProperties": {}
},
"notes": {
"type": "array",
"items": {
"type": "object",
"required": [
"text"
],
"properties": {
"text": {
"type": "string",
"description": "Note text."
},
"title": {
"type": "string",
"description": "Note title, e.g. \"WARNING\"."
},
"anchor": {
"type": "string",
"description": "Anchor that note references point at."
}
},
"description": "One registry note.",
"additionalProperties": false
},
"description": "Notes of the table read (of the registry, when listing), first page only."
},
"shown": {
"type": "number",
"description": "Results returned."
},
"notice": {
"type": "string",
"description": "Guidance on a miss, a cut list, or another condition."
},
"offset": {
"type": "number",
"description": "Matching records before this page, on pages after the first."
},
"source": {
"type": "object",
"required": [
"registry_id",
"url",
"fetched_at",
"stale"
],
"properties": {
"url": {
"type": "string",
"description": "The file fetched from iana.org."
},
"stale": {
"type": "boolean",
"description": "True when a refresh failed and a cached copy up to 7 days old answered."
},
"fetched_at": {
"type": "string",
"description": "ISO 8601 time of the last successful fetch or revalidation."
},
"registry_id": {
"type": "string",
"description": "Id of the registry file that answered."
},
"registry_updated": {
"type": "string",
"description": "The registry's own last-updated date; absent for the protocol index."
}
},
"description": "Provenance and freshness of the answer.",
"additionalProperties": false
},
"columns": {
"type": "array",
"items": {
"type": "string"
},
"description": "Field (XML element) names seen, in first-seen order."
},
"records": {
"type": "array",
"items": {
"type": "object",
"required": [
"fields",
"references"
],
"properties": {
"value": {
"type": "string",
"description": "The record's value_field cell; absent when the record has none."
},
"fields": {
"type": "object",
"description": "Whole values keyed by XML element name.",
"propertyNames": {
"type": "string"
},
"additionalProperties": {
"type": "string"
}
},
"updated": {
"type": "string",
"description": "Last-updated date."
},
"cut_fields": {
"type": "array",
"items": {
"type": "string"
},
"description": "Names of cut fields when present; omitted for whole records."
},
"references": {
"type": "array",
"items": {
"type": "object",
"required": [
"type",
"id"
],
"properties": {
"id": {
"type": "string",
"description": "E.g. \"RFC 9110\", a draft name, a registry id, or a URL."
},
"url": {
"type": "string",
"description": "URL of the reference."
},
"type": {
"enum": [
"rfc",
"draft",
"uri",
"registry",
"rfc-errata",
"note",
"text"
],
"type": "string",
"description": "Reference kind."
},
"label": {
"type": "string",
"description": "Label text, when it adds to id and section."
},
"section": {
"type": "string",
"description": "Section, e.g. \"15.5.5\"."
}
},
"description": "A defining reference.",
"additionalProperties": false
},
"description": "References on the record."
},
"registered": {
"type": "string",
"description": "Registration date."
}
},
"description": "One registry record.",
"additionalProperties": false
},
"description": "Whole records in registry order (with contains, records with a field equal to the words first), up to limit."
},
"truncated": {
"type": "boolean",
"description": "True when more matches exist than were returned."
},
"references": {
"type": "array",
"items": {
"type": "object",
"required": [
"type",
"id"
],
"properties": {
"id": {
"type": "string",
"description": "E.g. \"RFC 9110\", a draft name, a registry id, or a URL."
},
"url": {
"type": "string",
"description": "URL of the reference."
},
"type": {
"enum": [
"rfc",
"draft",
"uri",
"registry",
"rfc-errata",
"note",
"text"
],
"type": "string",
"description": "Reference kind."
},
"label": {
"type": "string",
"description": "Label text, when it adds to id and section."
},
"section": {
"type": "string",
"description": "Section, e.g. \"15.5.5\"."
}
},
"description": "A defining reference.",
"additionalProperties": false
},
"description": "The documents that define the table read."
},
"totalCount": {
"type": "number",
"description": "Matches before the limit was applied."
},
"description": {
"type": "string",
"description": "Description of the table read, or of the registry when listing; a YANG module registry names its module file here."
},
"next_cursor": {
"type": "string",
"description": "Pass as cursor, with the same filters, for the next page."
},
"registry_id": {
"type": "string",
"description": "Registry id."
},
"value_field": {
"type": "string",
"description": "The table's key column: each record's value comes from it, and the value filter matches it unless field names another."
},
"subregistries": {
"type": "array",
"items": {
"type": "object",
"required": [
"id",
"title",
"record_count"
],
"properties": {
"id": {
"type": "string",
"description": "Pass as subregistry."
},
"title": {
"type": "string",
"description": "Sub-registry title."
},
"record_count": {
"type": "number",
"description": "Records it holds."
}
},
"description": "One sub-registry.",
"additionalProperties": false
},
"description": "Tables to read next: every sub-registry when one must be chosen (records is then empty), or the tables nested directly in the table read, on its first page."
},
"registry_notes": {
"type": "array",
"items": {
"type": "object",
"required": [
"text"
],
"properties": {
"text": {
"type": "string",
"description": "Note text."
},
"title": {
"type": "string",
"description": "Note title, e.g. \"WARNING\"."
},
"anchor": {
"type": "string",
"description": "Anchor that note references point at."
}
},
"description": "One registry note.",
"additionalProperties": false
},
"description": "The registry root's notes and footnotes, on the first page of a sub-registry read; records cite them by anchor."
},
"registry_title": {
"type": "string",
"description": "Registry title."
},
"subregistry_id": {
"type": "string",
"description": "Id of the sub-registry the records come from."
},
"effective_limit": {
"type": "number",
"description": "The response limit after clamping, present when clamped."
},
"notes_truncated": {
"type": "boolean",
"description": "Indicates truncated notes when present; omitted for whole notes."
},
"requested_limit": {
"type": "number",
"description": "The requested limit, present when clamped."
},
"subregistry_title": {
"type": "string",
"description": "Title of that sub-registry."
},
"registration_ranges": {
"type": "array",
"items": {
"type": "object",
"required": [
"range"
],
"properties": {
"note": {
"type": "string",
"description": "Note on the range."
},
"range": {
"type": "string",
"description": "Allocation range, e.g. \"0x0000-0xBFFF\"."
},
"procedure": {
"type": "string",
"description": "Registration procedure."
}
},
"description": "One allocation range.",
"additionalProperties": false
},
"description": "Allocation ranges, when the table defines them."
},
"registration_procedure": {
"type": "string",
"description": "Registration rule of the table read, or of the registry when listing."
}
},
"additionalProperties": false
}iana_get_registry_records annotations
{
"readOnlyHint": true,
"openWorldHint": true,
"idempotentHint": true
}Prompts
0 advertised
Resources
1 advertised
iana-registries-guide
Trace protocol assignments to their defining documents with iana_* tools. Use when resolving an unfamiliar registry or code-point namespace, auditing RFC and draft references, or checking the current members and status of a standards series.
iana-registries-guide URI
skill://iana-registries-guide/SKILL.mdio.modelcontextprotocol/skills
io.modelcontextprotocol/skills URI template
skill://{+path}90-day uptime
A lightweight connection check about every six hours, sampled on hosts with many listings. It shows the server answered, not that its tools work.
- 2026-11-07: 2 of 2 checks answered
30-day availability
Aggregated from read-only remote checks; this is not a tool-execution or security guarantee.
- Successful checks
- 1 of 1 (100%)
- Average latency
- 744 ms
- 95th percentile latency
- 744 ms
Maintenance history
Public check and source-refresh events. Editorial and ownership records remain private.
- · probe · passed · 744 ms · metadata changed · 10 tool(s), 1 resource(s), 1 resource template(s), 0 prompt(s)
Connect from your client
Each snippet registers the same endpoint; pick the client you use.
Claude Code
Claude Code configuration
claude mcp add --transport http iana-registries-mcp-server-caseyjhand https://iana-registries.caseyjhand.com/mcpCodex
Codex configuration
codex mcp add iana-registries-mcp-server-caseyjhand --url https://iana-registries.caseyjhand.com/mcpCursor
Cursor configuration
{
"mcpServers": {
"iana-registries-mcp-server-caseyjhand": {
"url": "https://iana-registries.caseyjhand.com/mcp"
}
}
}Cline
Cline configuration
{
"mcpServers": {
"iana-registries-mcp-server-caseyjhand": {
"type": "streamableHttp",
"url": "https://iana-registries.caseyjhand.com/mcp",
"disabled": false
}
}
}VS Code
VS Code configuration
{
"servers": {
"iana-registries-mcp-server-caseyjhand": {
"type": "http",
"url": "https://iana-registries.caseyjhand.com/mcp"
}
}
}Gemini CLI
Gemini CLI configuration
gemini mcp add --transport http iana-registries-mcp-server-caseyjhand https://iana-registries.caseyjhand.com/mcpClaude Desktop
Claude Desktop configuration
https://iana-registries.caseyjhand.com/mcpWindsurf
Windsurf configuration
{
"mcpServers": {
"iana-registries-mcp-server-caseyjhand": {
"serverUrl": "https://iana-registries.caseyjhand.com/mcp"
}
}
}Let your agent find its tools
Find servers like iana-registries-mcp-server from your agent. Add Koskamo once to search the index for endpoints, access requirements, and client setup. Public discovery needs no key.