A2A Protocol

Agent2Agent (A2A) Protocol is an open standard that enables communication and collaboration between AI agents. A2A Protocol is the common language for agent interoperability with frameworks and different vendors.

This connector has the following capabilities:

  • Workato recipes can communicate with any A2A-compliant AI agent server.
  • Invoke AI agents as steps inside an automation workflow, wait for results, and act on the output.
  • Cover the full range of integration patterns from synchronous blocking calls, to fire-and-check async workflows.
  • Agents built on different frameworks can discover each other, delegate tasks, and exchange results over HTTP/JSON-RPC.

Refer to the A2A Protocol documentation for information about the protocol's core concepts.

A2A Protocol compatible agents

The following agents are compatible with the A2A Protocol connector:

AgentFrameworkAuthentication
Google ADK Purchasing ConciergeGoogle ADK (Python)N/A
LangGraph / LangSmith A2A EndpointLangChain / LangGraphBearer token
CrewAI + Vertex AICrewAI + Gemini 2.5Google OAuth2 / Bearer
Amazon Bedrock AgentCoreAWSAWS SigV4 / Bearer. Bedrock AgentCore connection using A2A Protocol requires additional configuration.
Azure AI Foundry A2AAzureAzure AD Bearer token
a2a-samples (GitHub)Python or JSConfigurable

Multi-agent architecture

A2A Protocol supports using multiple agents with the following architecture:

  • One Agent Card per domain
  • Distinct paths for each agent on the same server
  • Separate Agent Cards for each agent on the same server
  • One connection per agent. You must create separate connections for each agent.

Skills

Skills used in A2A Protocol connections are only shown in hint text on the Message input field. The connector doesn't send a skill ID or skill reference in the message payload.

Install A2A Protocol from the community library

Complete the following steps to install the A2A Protocol connector from the community library:

Complete the following steps to install the A2A Protocol connector from the community library:

1

Open the recipe editor and search for a connector. Alternatively, you can search for a connector in the community library.

Search for recipe editorSearch for community connectors in the recipe editor

2

Select the community connector you plan to install.

3

Click Install to install the connector from the community library.

Click installClick Install

4

Select Release connector. Alternatively, select Review code to review and modify the connector code before releasing it to the workspace.

Release connectorRelease the connector

5

Summarize any changes you made to the connector, then click Release to allow workspace collaborators to use the connector in recipes.

The Confirm release dialogThe Confirm release dialog

Obtain required credentials

Each agent defines its own authentication requirements. Review your agent's documentation to determine which authentication method it supports and how to obtain the required credentials. The following table includes A2A Protocol supported authentication methods:

Authentication methodWhen to useRequired credentials
OAuth 2.0 client credentialsUse for server-to-server authentication.
  • Client ID
  • Client secret
  • Token URL
  • Scope
OAuth 2.0 authorization codeUse for agents that act on behalf of the authenticated user.
  • Client ID
  • Client secret
  • Authorization URL
  • Token URL
  • Scope
Bearer tokenUse for simple API gateways.Bearer token
API keyUse for self-hosted or internal agents.API key
NoneUse if the API is public and doesn't require authentication.None

Register Workato as an OAuth client

OAuth 2.0 connections require you to register Workato as an OAuth client.

Complete the following steps to register Workato as an OAuth client in your A2A Protocol compliant agent:

1

Go to your application’s Developer or API settings page.

2

Create a new OAuth client or application.

3

Set the Redirect URI to: https://www.workato.com/oauth/callback

4

Copy the authentication values, such as Client ID, Client secret, Authorization URL, and Token URL from your application.

Verify your credentials

Test your credentials using a tool such as curl or Postman before establishing your connection to confirm your credentials are valid.

Ensure you can:

  • Call the /a2a endpoint successfully
  • Receive a valid JSON response
  • Retrieve an access token (for OAuth connections)

Connect to A2A Protocol in Workato

Complete the following steps to set up an A2A Protocol connection in Workato:

1

Click Create > Connection.

2

Search for A2A Protocol and select it as your app.

3

Enter a name for your connection in the Connection name field.

A2A Protocol connection setupSet up your A2A Protocol connection

4

Use the Location drop-down menu to select the project where you plan to store the connection.

5

Enter the full URL of the A2A Protocol agent endpoint in the Agent URL field. For example, https://agent.acme.com/a2a/billing.

6

Use the Authentication type drop-down menu to select an authentication type and provide the required credentials for your selection.

7

Click Connect.

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