A Capability Statement documents a set of capabilities (behaviors) of a FHIR Server for a particular version of FHIR that may be used as a statement of actual server functionality or a statement of required or desired server implementation.

Applications may implement multiple versions (see Managing Multiple Versions, and the $versions operation). If they do, then a CapabilityStatement2 describes the system's support for a particular version of FHIR, and the server will have multiple statements, one for each version.

An absolute URI that is used to identify this capability statement2 when it is referenced in a specification, model, design or an instance; also called its canonical identifier. This SHOULD be globally unique and SHOULD be a literal address at which at which an authoritative instance of this capability statement2 is (or will be) published. This URL can be the target of a canonical reference. It SHALL remain the same when the capability statement2 is stored on different servers.

Allows the capability statement2 to be referenced by a single globally unique identifier.

Can be a urn:uuid: or a urn:oid: but real http: addresses are preferred. Multiple instances may share the same URL if they have a distinct version.

The determination of when to create a new version of a resource (same url, new version) vs. defining a new artifact is up to the author. Considerations for making this decision are found in Technical and Business Versions.

In some cases, the resource can no longer be found at the stated url, but the url itself cannot change. Implementations can use the meta.source element to indicate where the current master source of the resource can be found.

The identifier that is used to identify this version of the capability statement2 when it is referenced in a specification, model, design or instance. This is an arbitrary value managed by the capability statement2 author and is not expected to be globally unique. For example, it might be a timestamp (e.g. yyyymmdd) if a managed version is not available. There is also no expectation that versions can be placed in a lexicographical sequence.

There may be different capability statement2 instances that have the same identifier but different versions. The version can be appended to the url in a reference to allow a reference to a particular business version of the capability statement2 with the format [url]|[version].

A natural language name identifying the capability statement2. This name should be usable as an identifier for the module by machine processing applications such as code generation.

Support human navigation and code generation.

The name is not expected to be globally unique. The name should be a simple alphanumeric type name to ensure that it is machine-processing friendly.

A short, descriptive, user-friendly title for the capability statement2.

This name does not need to be machine-processing friendly and may contain punctuation, white-space, etc.

The status of this capability statement2. Enables tracking the life-cycle of the content.

Allows filtering of capability statement2s that are appropriate for use versus not.This is not intended for use with actual capability statements, but where capability statements are used to describe possible or desired systems.

A Boolean value to indicate that this capability statement2 is authored for testing purposes (or education/evaluation/marketing) and is not intended to be used for genuine usage.

Enables experimental content to be developed following the same lifecycle that would be used for a production-level capability statement2.

Allows filtering of capability statement2s that are appropriate for use versus not.

The date (and optionally time) when the capability statement2 was published. The date must change when the business version changes and it must change if the status code changes. In addition, it should change when the substantive content of the capability statement2 changes.

Note that this is not the same as the resource last-modified-date, since the resource may be a secondary representation of the capability statement2. Additional specific dates may be added as extensions or be found by consulting Provenances associated with past versions of the resource.

The name of the organization or individual that published the capability statement2.

Helps establish the "authority/credibility" of the capability statement2. May also allow for contact.

Usually an organization but may be an individual. The publisher (or steward) of the capability statement2 is the organization or individual primarily responsible for the maintenance and upkeep of the capability statement2. This is not necessarily the same individual or organization that developed and initially authored the content. The publisher is the primary point of contact for questions or issues with the capability statement2. This item SHOULD be populated unless the information is available from context.

Contact details to assist a user in finding and communicating with the publisher.

May be a web site, an email address, a telephone number, etc.

A free text natural language description of the capability statement2 from a consumer's perspective. Typically, this is used when the capability statement describes a desired rather than an actual solution, for example as a formal expression of requirements as part of an RFP.

This description can be used to capture details such as why the capability statement2 was built, comments about misuse, instructions for clinical use and interpretation, literature references, examples from the paper world, etc. It is not a rendering of the capability statement2 as conveyed in the 'text' field of the resource itself. This item SHOULD be populated unless the information is available from context (e.g. the language of the capability statement2 is presumed to be the predominant language in the place the capability statement2 was created).This does not need to be populated if the description is adequately implied by the software or implementation details.

The content was developed with a focus and intent of supporting the contexts that are listed. These contexts may be general categories (gender, age, ...) or may be references to specific programs (insurance plans, studies, ...) and may be used to assist with indexing and searching for appropriate capability statement2 instances.

Assist in searching for appropriate content.

When multiple useContexts are specified, there is no expectation that all or any of the contexts apply.

A legal or geographic region in which the capability statement2 is intended to be used.

It may be possible for the capability statement2 to be used in jurisdictions other than those for which it was originally designed or intended.

Explanation of why this capability statement2 is needed and why it has been designed as it has.

This element does not describe the usage of the capability statement2. Instead, it provides traceability of ''why'' the resource is either needed or ''why'' it is defined as it is. This may be used to point to source materials or specifications that drove the structure of this capability statement2.

A copyright statement relating to the capability statement2 and/or its contents. Copyright statements are generally legal restrictions on the use and publishing of the capability statement2.

Consumers must be able to determine any legal restrictions on the use of the capability statement2 and/or its content.

The way that this statement is intended to be used, to describe an actual running instance of software, a particular product (kind, not instance of software) or a class of implementation (e.g. a desired purchase).

Allow searching the 3 modes.

Reference to a canonical URL of another CapabilityStatement2 that this software implements. This capability statement is a published API description that corresponds to a business service. The server may actually implement a subset of the capability statement it claims to implement, so the capability statement must specify the full capability details.

HL7 defines the following Services: Terminology Service.

Many Implementation Guides define additional services.

Reference to a canonical URL of another CapabilityStatement2 that this software adds to. The capability statement automatically includes everything in the other statement, and it is not duplicated, though the server may repeat the same resources, interactions and operations to add additional details to them.

the contents of any directly or indirectly imported CapabilityStatement2s SHALL NOT overlap, i.e. they cannot refer to the same rest/resource, operations/name, searchparam/name, interaction/code, messaging/endpoint, document/mode pair.

A capability statement that imports another CapabilityStatement2 automatically instantiates it too (though this is often not a very useful statement for the kinds of CapabilityStatement2s that are suitable for importing).

Software that is covered by this capability statement. It is used when the capability statement describes the capabilities of a particular software version, independent of an installation.

Name the software is known by.

The version identifier for the software covered by this statement.

If possible, a version should be specified, as statements are likely to be different for different versions of software.

Date this version of the software was released.

Identifies a specific implementation instance that is described by the capability statement - i.e. a particular installation, rather than the capabilities of a software program.

Information about the specific installation that this capability statement relates to.

An absolute base URL for the implementation. This forms the base for REST interfaces as well as the mailbox and document interfaces.

The organization responsible for the management of the instance and oversight of the data on the server at the specified URL.

The version of the FHIR specification that this CapabilityStatement2 describes (which SHALL be the same as the FHIR version of the CapabilityStatement2 itself). There is no default value.

Servers may implement multiple versions (see Managing Multiple Versions, and the $versions operation). If they do, and the CapabilityStatement2 is requested from the server, then this fhirVersion will be either the version requested, or the server's default version.

A list of the formats supported by this implementation using their content types.

"xml", "json" and "ttl" are allowed, which describe the simple encodings described in the specification (and imply appropriate bundle support). Otherwise, mime types are legal here.

A list of the patch formats supported by this implementation using their content types.

At present, the patch mime types application/json-patch+json and application/xml-patch+xml are legal. Generally, if a server supports PATCH, it would be expected to support the patch formats and match the formats it supports, but this is not always possible or necessary.

A list of implementation guides that the server does (or should) support in their entirety.

A definition of the restful capabilities of the solution, if any.

Multiple repetitions allow definition of both client and/or server behaviors or possibly behaviors under different configuration settings (for software or requirements statements).

Identifies whether this portion of the statement is describing the ability to initiate or receive restful operations.

Information about the system's restful capabilities that apply across all applications, such as security.

A specification of the restful capabilities of the solution for a specific resource type.

Max of one repetition per resource type.

A type of resource exposed via the restful interface.

A specification of the profile that describes the solution's overall support for the resource, including any constraints on cardinality, bindings, lengths or other limitations. See further discussion in Using Profiles.

The profile applies to all resources of this type - i.e. it is the superset of what is supported by the system.

A list of profiles that represent different use cases supported by the system. For a server, "supported by the system" means the system hosts/produces a set of resources that are conformant to a particular profile, and allows clients that use its services to search using this profile and to find appropriate data. For a client, it means the system will search by this profile and process data according to the guidance implicit in the profile. See further discussion in Using Profiles.

Supported profiles are different than the profile that applies to a particular resource in .rest.resource.profile. The resource profile is a general statement of what features of the resource are supported overall by the system - the sum total of the facilities it supports. A supported profile is a deeper statement about the functionality of the data and services provided by the server (or used by the client). A typical case is a laboratory system that produces a set of different reports - this is the list of types of data that it publishes. A key aspect of declaring profiles here is the question of how the client converts knowledge that the server publishes this data into working with the data; the client can inspect individual resources to determine whether they conform to a particular profile, but how does it find the ones that do? It does so by searching using the _profile parameter, so any resources listed here must be valid values for the _profile resource (using the identifier in the target profile).

Additional information about the resource type used by the system.

Identifies a restful operation supported by the solution.

In general, a Resource will only appear in a CapabilityStatement2 if the server actually has some capabilities - e.g. there is at least one interaction supported. However interactions can be omitted to support summarization (_summary = true).

Coded identifier of the operation, supported by the system resource.

Guidance specific to the implementation of this operation, such as 'delete is a logical delete' or 'updates are only allowed with version id' or 'creates permitted from pre-authorized certificates only'.

REST allows a degree of variability in the implementation of RESTful solutions that is useful for exchange partners to be aware of.

Search parameters for implementations to support and/or make use of - either references to ones defined in the specification, or additional ones defined for/by the implementation.

The search parameters should include the control search parameters such as _sort, _count, etc. that also apply to this resource (though many will be listed at CapabilityStatement2.rest.searchParam). The behavior of some search parameters may be further described by other code or extension elements, or narrative within the capability statement or linked SearchParameter definitions.

The name of the search parameter used in the interface.

Parameter names cannot overlap with standard parameter names, and standard parameters cannot be redefined.

An absolute URI that is a formal reference to where this parameter was first defined, so that a client can be confident of the meaning of the search parameter (a reference to SearchParameter.url). This element SHALL be populated if the search parameter refers to a SearchParameter defined by the FHIR core specification or externally defined IGs.

This SHOULD be present, and matches refers to a SearchParameter by its canonical URL. If systems wish to document their support for modifiers, comparators, target resource types, and chained parameters, they should do using a search parameter resource. This element SHALL be populated if the search parameter refers to a SearchParameter defined by the FHIR core specification or externally defined IGs.

The type of value a search parameter refers to, and how the content is interpreted.

While this can be looked up from the definition, it is included here as a convenience for systems that autogenerate a query interface based on the server capability statement. It SHALL be the same as the type in the search parameter definition.

This allows documentation of any distinct behaviors about how the search parameter is used. For example, text matching algorithms.

Definition of an operation or a named query together with its parameters and their meaning and type. Consult the definition of the operation for details about how to invoke the operation, and the parameters.

Operations linked from CapabilityStatement2.rest.resource.operation must have OperationDefinition.type = true or OperationDefinition.instance = true.

If an operation that is listed in multiple CapabilityStatement2.rest.resource.operation (e.g. for different resource types), then clients should understand that the operation is only supported on the specified resource types, and that may be a subset of those listed in OperationDefinition.resource.

The name of the operation or query. For an operation, this is the name prefixed with $ and used in the URL. For a query, this is the name used in the _query parameter when the query is called.

The name here SHOULD be the same as the name in the definition, unless there is a name clash and the name cannot be used. The name does not include the "$" portion that is always included in the URL.

Where the formal definition can be found. If a server references the base definition of an Operation (i.e. from the specification itself such as http://hl7.org/fhir/OperationDefinition/ValueSet-expand), that means it supports the full capabilities of the operation - e.g. both GET and POST invocation. If it only supports a subset, it must define its own custom OperationDefinition with a 'base' of the original OperationDefinition. The custom definition would describe the specific subset of functionality supported.

This can be used to build an HTML form to invoke the operation, for instance.

Documentation that describes anything special about the operation behavior, possibly detailing different behavior for system, type and instance-level invocation of the operation.

A specification of restful operations supported by the system.

A coded identifier of the operation, supported by the system.

Guidance specific to the implementation of this operation, such as limitations on the kind of transactions allowed, or information about system wide search is implemented.

Search parameters that are supported for searching all resources for implementations to support and/or make use of - either references to ones defined in the specification, or additional ones defined for/by the implementation.

Typically, the only search parameters supported for all searches are those that apply to all resources - tags, profiles, text search etc. These search parameters should include the control search parameters such as _sort, _count, etc. that also apply to this resource (though many will be listed at CapabilityStatement2.rest.searchParam). The behavior of some search parameters may be further described by other code or extension elements, or narrative within the capability statement or linked SearchParameter definitions.

Definition of an operation or a named query together with its parameters and their meaning and type.

CapabilityStatement2.rest.operation is for operations invoked at the system level, or for operations that are supported across multiple resource types. Operations linked from CapabilityStatement2.rest.operation must have OperationDefinition.system = true, or more than one Operation.resource.

An absolute URI which is a reference to the definition of a compartment that the system supports. The reference is to a CompartmentDefinition resource by its canonical URL .

At present, the only defined compartments are at CompartmentDefinition.