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Nappai Documentation

A2A Agent

A2A Agent connects your flow to an external agent that uses the A2A (Agent2Agent) standard: for example agents built with Google’s tools or with the protocol’s official kit, or a NappAI flow published with A2A Server. You give it the agent’s address; the component reads its card, adapts to the version of the standard that agent uses, sends it the message and waits for it to finish, even if the task takes several minutes.

You can use it in two ways:

  • Directly: you pass it a message and it returns the external agent’s answer.
  • As a tool for an agent: connect its Tool output to an agent’s tools. The tool takes the name and description of the external agent’s card, and your agent decides when to ask it. With several A2A Agent components connected to the same agent, it shares the work among several external agents.

When to use it

  • Ask a supplier’s specialised agent (for example, a logistics one) from your customer service flow.
  • Build a coordinator agent that delegates to agents on different platforms depending on the question.
  • Chain NappAI flows in different accounts that are published with A2A Server.
  • Make use of agents that other teams in your company have already built outside NappAI.

Configuration

FieldWhat it does
Agent URL (required)The address of the external agent, or of its card. Whoever publishes the agent gives it to you.
MessageWhat you want to ask the agent. When you use it as a tool, leave it empty: your agent writes it.
API KeyOptional: only if the external agent asks for a key. It is filled in by the A2A Agent credential. NappAI sends it the way the agent’s card indicates. See Credentials.

Advanced

FieldWhat it does
Keep ConversationKeeps the same conversation with the external agent for the whole session, so it remembers what you already told it. On by default.
Max Wait (seconds)How long to wait for the external agent to finish. Defaults to 300 seconds; between 10 and 900. If it does not finish in time, it is asked to stop the task and the component stops, saying the time ran out.
Extra HeadersAdditional data some agents ask for on every call. Use it only if the agent’s provider says so.

Output

  • Response: the external agent’s answer, as a message. Connect it to a Chat Output or another component.
  • Agent Card: the external agent’s card, with its name, description and skills.
  • Tool: the external agent as a tool, to connect to an agent’s tools.

If the external agent sends back files (for example, an image it generated), they appear attached to the answer in the chat.

If the external agent needs more information to continue, the answer says so, so your agent can ask the user for it. If the external agent fails, rejects the task, does not answer or does not accept the key, the component stops with the reason.

Example

A travel agency has an assistant in NappAI that serves its customers on WhatsApp. Its hotel supplier publishes an A2A agent that checks availability and prices. The agency adds an A2A Agent with that agent’s address and the credential the supplier gave it, and connects it to its assistant’s tools. When a customer asks “is there a double room in Seville next weekend?”, the assistant asks the supplier’s agent and answers with the real availability.