// Copyright 2026 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

syntax = "proto3";

package google.cloud.agentregistry.v1;

import "google/api/field_behavior.proto";
import "google/api/field_info.proto";
import "google/api/resource.proto";
import "google/cloud/agentregistry/v1/properties.proto";
import "google/protobuf/struct.proto";
import "google/protobuf/timestamp.proto";

option csharp_namespace = "Google.Cloud.AgentRegistry.V1";
option go_package = "cloud.google.com/go/agentregistry/apiv1/agentregistrypb;agentregistrypb";
option java_multiple_files = true;
option java_outer_classname = "AgentProto";
option java_package = "com.google.cloud.agentregistry.v1";
option php_namespace = "Google\\Cloud\\AgentRegistry\\V1";
option ruby_package = "Google::Cloud::AgentRegistry::V1";

// Represents an Agent.
// "A2A" below refers to the Agent-to-Agent protocol.
message Agent {
  option (google.api.resource) = {
    type: "agentregistry.googleapis.com/Agent"
    pattern: "projects/{project}/locations/{location}/agents/{agent}"
    plural: "agents"
    singular: "agent"
  };

  // Represents the protocol of an Agent.
  message Protocol {
    // The type of the protocol.
    enum Type {
      // Unspecified type.
      TYPE_UNSPECIFIED = 0;

      // The interfaces point to an A2A Agent following the A2A
      // specification.
      A2A_AGENT = 1;

      // Agent does not follow any standard protocol.
      CUSTOM = 2;
    }

    // Output only. The type of the protocol.
    Type type = 1 [(google.api.field_behavior) = OUTPUT_ONLY];

    // Output only. The version of the protocol, for example, the A2A Agent Card
    // version.
    string protocol_version = 2 [(google.api.field_behavior) = OUTPUT_ONLY];

    // Output only. The connection details for the Agent.
    repeated Interface interfaces = 3
        [(google.api.field_behavior) = OUTPUT_ONLY];
  }

  // Represents the skills of an Agent.
  message Skill {
    // Output only. A unique identifier for the agent's skill.
    string id = 1 [(google.api.field_behavior) = OUTPUT_ONLY];

    // Output only. A human-readable name for the agent's skill.
    string name = 2 [(google.api.field_behavior) = OUTPUT_ONLY];

    // Output only. A more detailed description of the skill.
    string description = 3 [(google.api.field_behavior) = OUTPUT_ONLY];

    // Output only. Keywords describing the skill.
    repeated string tags = 4 [(google.api.field_behavior) = OUTPUT_ONLY];

    // Output only. Example prompts or scenarios this skill can handle.
    repeated string examples = 5 [(google.api.field_behavior) = OUTPUT_ONLY];
  }

  // Full Agent Card payload, often obtained from the A2A Agent Card.
  message Card {
    // Represents the type of the agent card.
    enum Type {
      // Unspecified type.
      TYPE_UNSPECIFIED = 0;

      // Indicates that the card is an A2A Agent Card.
      A2A_AGENT_CARD = 1;
    }

    // Output only. The type of agent card.
    Type type = 1 [(google.api.field_behavior) = OUTPUT_ONLY];

    // Output only. The content of the agent card.
    google.protobuf.Struct content = 2
        [(google.api.field_behavior) = OUTPUT_ONLY];
  }

  // Identifier. The resource name of an Agent.
  // Format: `projects/{project}/locations/{location}/agents/{agent}`.
  string name = 1 [(google.api.field_behavior) = IDENTIFIER];

  // Output only. A stable, globally unique identifier for agents.
  string agent_id = 2 [(google.api.field_behavior) = OUTPUT_ONLY];

  // Output only. The location where agent is hosted. The value is defined by
  // the hosting environment (i.e. cloud provider).
  string location = 4 [(google.api.field_behavior) = OUTPUT_ONLY];

  // Output only. The display name of the agent, often obtained from the A2A
  // Agent Card.
  string display_name = 5 [(google.api.field_behavior) = OUTPUT_ONLY];

  // Output only. The description of the Agent, often obtained from the A2A
  // Agent Card. Empty if Agent Card has no description.
  string description = 6 [(google.api.field_behavior) = OUTPUT_ONLY];

  // Output only. The version of the Agent, often obtained from the A2A Agent
  // Card. Empty if Agent Card has no version or agent is not an A2A Agent.
  string version = 7 [(google.api.field_behavior) = OUTPUT_ONLY];

  // Output only. The connection details for the Agent.
  repeated Protocol protocols = 8 [(google.api.field_behavior) = OUTPUT_ONLY];

  // Output only. Skills the agent possesses, often obtained from the A2A Agent
  // Card.
  repeated Skill skills = 9 [(google.api.field_behavior) = OUTPUT_ONLY];

  // Output only. A universally unique identifier for the Agent.
  string uid = 10 [
    (google.api.field_info).format = UUID4,
    (google.api.field_behavior) = OUTPUT_ONLY
  ];

  // Output only. Create time.
  google.protobuf.Timestamp create_time = 11
      [(google.api.field_behavior) = OUTPUT_ONLY];

  // Output only. Update time.
  google.protobuf.Timestamp update_time = 12
      [(google.api.field_behavior) = OUTPUT_ONLY];

  // Output only. Attributes of the Agent.
  // Valid values:
  //
  //  * `agentregistry.googleapis.com/system/Framework`: {"framework":
  //  "google-adk"} - the agent framework used to develop the Agent. Example
  //  values: "google-adk", "langchain", "custom".
  //  * `agentregistry.googleapis.com/system/RuntimeIdentity`: {"principal":
  //  "principal://..."} - the runtime identity associated with the Agent.
  //  * `agentregistry.googleapis.com/system/RuntimeReference`: {"uri": "//..."}
  //  - the URI of the underlying resource hosting the Agent, for
  //  example, the Reasoning Engine URI.
  map<string, google.protobuf.Struct> attributes = 13
      [(google.api.field_behavior) = OUTPUT_ONLY];

  // Output only. Full Agent Card payload, when available.
  Card card = 14 [(google.api.field_behavior) = OUTPUT_ONLY];
}