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Version: dev

Connect your first tool

A tool gives an agent the ability to do work. A Rossoctl tool is a container that uses the MCP protocol on the /mcp endpoint. This procedure deploys a tool and connects an agent to it.

Step 1: deploy the tool​

  1. In the console, select Tools, and then select Import new tool.

  2. Select Deploy from existing image. Enter this image address:

    ghcr.io/rossoctl/examples/weather-tool:latest

  3. Add the environment variables that the tool needs. An example is a key for an external service.

  4. To reach the tool directly, select Enable external access to the tool endpoint.

  5. Select Deploy.

Rossoctl creates a Deployment and a Service, and adds the workload to the platform in the same way that it adds an agent.

For more tools, see examples/mcp.

Step 2: give the address to an agent​

An agent reads the address of a tool from an environment variable.

VariableUse it when
MCP_URLThe agent uses one tool, or the agent uses the MCP Gateway.
MCP_URLSThe agent uses more than one tool directly. Separate the addresses with commas.

For a tool in the same namespace as the agent, use this value:

MCP_URL=http://weather-tool:8080/mcp

Set the variable when you deploy the agent. To change an agent that already runs, use this command:

kubectl set env deployment/weather-service -n <namespace> \
  MCP_URL="http://weather-tool:8080/mcp"
For an agent in a sandbox

The kubectl set env command does not operate on a Sandbox resource. You must change the specification and then delete the pod. See Sandboxes.

Step 3: confirm that the agent can call the tool​

Open the Chat tab of the agent. Ask a question that only the tool can answer.

If the agent gives a correct answer, the connection operates. If the agent invents an answer, or reports that it has no tool, the address is wrong or the tool is not ready.

Confirm that the tool runs:

kubectl get pods -n <namespace> -l app=weather-tool

For many tools and many agents​

One address for each pair of agent and tool does not scale. The MCP Gateway gives each agent one address for all tools, and adds a prefix to each tool name to prevent a conflict.

See MCP Gateway.

To build the tool from source instead​

The requirements are the same as the requirements for an agent: the --with-builds option, a GitHub repository, and a subdirectory that contains a Dockerfile. For a tool you can also select the target registry and the image tag. See Deploy a tool.

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