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Updated October 3, 2026

Give AI agents MCP tools

Overview

Once you've connected an MCP server, you decide which of its tools each AI agent may use. An agent only ever sees the tools you've selected for it. Agents with no MCP tools selected never contact your MCP servers.

During a conversation, the agent decides by itself when a tool would help answer the visitor. For example, if a visitor asks "Where is my application?", an agent with an "Applications · Get status" tool can call it and reply with the real status.

Steps

Choose tools for an agent

  1. Go to AI → AI agents and click Edit on the agent. You can also do this while creating a new agent.
  2. Find MCP tools. The list shows every tool from your active MCP servers, named "Server name · Tool name".
  3. Select the tools this agent may use. Select only the ones it needs.
  4. Click Update Agent (or Create Agent).
  5. Click Publish on the agent's card. Your chats keep using the last published version until you do.

If you see "No MCP tools available", you haven't connected a server yet, the server is paused, or it couldn't be reached. See Connect MCP servers.

Help the agent use tools well

The tool descriptions come from the MCP server, but you can guide the agent in its Agent Instructions. For example:

  • "When a visitor asks about their application, ask for their application number, then use the Get status tool."
  • "Never change a member's details without first confirming the change with the visitor."

Test it

  1. Open Chat test with a chat that uses the agent.
  2. Ask a question the tool can answer.
  3. Check that the reply includes the information from your system.

See Test your chat.

What happens when a tool fails

  • If a server is unreachable when a conversation starts, its tools are left out for that conversation. The agent still answers using its instructions and knowledge base.
  • If a tool returns an error, the agent is told about it and can explain the problem or offer another way to help.
  • Very long tool results are shortened before the agent reads them. Tools that return focused results work best.

Tips

  • Give an agent only the tools it needs. Fewer, clearer tools lead to better choices by the AI.
  • Be careful with tools that change data, such as update or delete tools. Only give them to agents whose instructions say when to use them and require confirmation.
  • To see which tools the AI called, and whether each call worked, select the conversation in Chat → Conversations and check Tool executions, or click Show AI Details on a reply. See View conversations.
  • Each tool call adds an extra AI step to the reply, which uses more AI credits. See AI credits.
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