build: locally generate pydantic v2 models via datamodel-codegen

Signed-off-by: Shingo OKAWA <[email protected]>

Author: ognis1205

src/a2a/types.py

@@ -62,6 +62,26 @@ class AgentCapabilities(BaseModel):
     """
 
 
+class AgentLinkTarget(BaseModel):
+    """
+    Represents a Link Target Object that specifically points to an agent card
+    in JSON format. This is a specialization of the generic LinkTarget,
+    with a fixed media type of "application/json" as required for agent metadata.
+    """
+
+    href: str
+    """
+    The target URI of the link.
+    MUST be a valid URI reference (RFC 3986).
+    SHOULD NOT be a relative reference.
+    """
+    type: Literal['application/json'] = 'application/json'
+    """
+    The media type of the target resource.
+    MUST be "application/json" to indicate the agent card is in JSON format.
+    """
+
+
 class AgentProvider(BaseModel):
     """
     Represents the service provider of an agent.
@@ -484,7 +504,52 @@ class JSONRPCSuccessResponse(BaseModel):
     """
 
 
-class Role(str, Enum):
+class LinkContext(BaseModel):
+    """
+    Represents a Link Context Object as defined in RFC 9264 Section 4.2.2.
+    See: https://www.rfc-editor.org/rfc/rfc9264#section-4.2.2
+    """
+
+    anchor: str | None = None
+    """
+    The URI reference representing the link context.
+    MUST be a valid URI reference (RFC 3986).
+    SHOULD NOT be a relative reference.
+    """
+
+
+class LinkTarget(BaseModel):
+    """
+    Represents a Link Target Object as defined in RFC 9264 Section 4.2.3.
+    See: https://www.rfc-editor.org/rfc/rfc9264#section-4.2.3
+
+    While not a complete implementation of all target attributes defined in
+    RFC 8288, this interface captures the minimal structure required for the
+    current use case and leaves room for extension.
+    """
+
+    href: str
+    """
+    The target URI of the link.
+    MUST be a valid URI reference (RFC 3986).
+    SHOULD NOT be a relative reference.
+    """
+
+
+class Linkset(BaseModel):
+    """
+    Represents a Linkset document as defined in RFC 9264.
+    See: https://www.rfc-editor.org/rfc/rfc9264
+    """
+
+    linkset: list[LinkContext]
+    """
+    An array of Link Context Objects.
+    Each object defines a set of related links for a given anchor (context URI).
+    """
+
+
+class Role(Enum):
     """
     Message sender's role
     """
@@ -816,6 +881,25 @@ class A2AError(
     )
 
 
+class AgentLinkContext(BaseModel):
+    """
+    Represents a Link Context object specifically for agents.
+    Extends the general LinkContext structure by requiring an `anchor` field
+    and including a `describedby` relation to link to the agent's card endpoint.
+    """
+
+    anchor: str
+    """
+    A URI reference identifying the agent's endpoint.
+    MUST be a valid URI reference (RFC 3986).
+    SHOULD NOT be a relative reference.
+    """
+    describedby: list[AgentLinkTarget]
+    """
+    A list of links that describe the agent's metadata (agent card).
+    """
+
+
 class CancelTaskRequest(BaseModel):
     """
     JSON-RPC request model for the 'tasks/cancel' method.
@@ -1058,6 +1142,21 @@ class SetTaskPushNotificationConfigSuccessResponse(BaseModel):
     """
 
 
+class AgentCatalog(BaseModel):
+    """
+    Represents an API Catalog document, extending the Linkset structure defined in RFC 9264.
+    This specialized catalog uses AgentLinkContext objects to describe agent-specific metadata.
+    See: https://www.ietf.org/archive/id/draft-ietf-httpapi-api-catalog-08.html
+    """
+
+    linkset: list[AgentLinkContext]
+    """
+    An array of AgentLinkContext objects.
+    Each object uses the `anchor` to specify the agent’s endpoint and the `describedby` link to
+    indicate the endpoint of its agent card.
+    """
+
+
 class Artifact(BaseModel):
     """
     Represents an artifact generated for a task.