Agentic AI โ Week 1, Day 7
What We're Going to Cover
Last week you built a workout-plan agent for FitPath. It could plan sessions and call tools โ your custom MCP server โ to read and write data. That's an agent using tools.
Today you're building something different: a second, independent agent that your workout agent can discover and delegate to, as a peer โ not absorb as another tool. That's the distinction between MCP and A2A that we just covered on slides, and by the end of this hour it won't be a slide anymore. It'll be two workflows in your own n8n workspace, actually talking to each other over the A2A protocol.
Agentic AI โ Week 1, Day 7
Context
FitPath wants to add nutrition guidance without rebuilding the workout agent from scratch. The product team's instinct is: "just give the workout agent a nutrition skill." Your job today is to build the alternative โ a standalone Nutrition Agent, with its own identity, its own skill, and its own Agent Card โ and prove that the workout agent can find it and hand it a task, the same way it could hand a task to a human specialist on the FitPath team.
You'll build both sides yourself, in the same n8n workspace:
- The Nutrition Agent โ the server side. It advertises what it can do via an Agent Card, and receives tasks over A2A.
- The Workout Agent (stand-in) โ the client side. It sends a real task to the Nutrition Agent and waits for the result.
You're working with Sam Whitaker today โ clean profile, no complications. The point of this exercise is the mechanics of the handshake, not edge cases.
Agentic AI โ Week 1, Day 7
Setup
- Your n8n login (provided by your facilitator) โ this is a private workspace; your workflows aren't visible to other participants.
- The A2A node set is already installed on the instance: A2A Remote Agent Server, A2A Client Agent, A2A Agent Registry.
- Sam Whitaker's profile (carried forward from Day 2 onward).
- Your Day 4 workout agent, open in another tab, for reference only โ you're not editing it today.
Agentic AI โ Week 1, Day 7
Steps
Part 1 โ Build the Nutrition Agent (15 min)
- Create a new workflow. Name it
FitPath โ Nutrition Agent. - Define one skill: something like "suggest a meal plan adjustment based on a logged workout's intensity." Keep the logic simple โ a templated response is fine (e.g., if intensity is "high," suggest an extra 20g protein and a electrolyte reminder). The point is not nutrition science; it's a working skill with a real input and a real output.
- Add the A2A Remote Agent Server node and configure it to expose that skill.
- Fill out the Agent Card: name, description, the skill you just defined, and the endpoint. This is the part participants skip when they're rushing โ don't. A vague or incomplete Agent Card is a realistic failure mode, and you'll feel why once Part 2 can't find your agent.
- Save and activate the workflow.
Part 2 โ Build the Workout Agent stand-in (15 min)
- Create a second workflow. Name it
FitPath โ Workout Agent (A2A client). - Add an A2A Client Agent node.
- Point it at your Nutrition Agent's endpoint from Part 1.
- Construct a task: "Sam Whitaker just logged a high-intensity leg day โ request a meal plan adjustment."
- Send it.
Part 3 โ Run it and watch the round trip (10 min)
- Trace the task through its lifecycle โ submitted โ working โ completed โ in the execution log.
- Confirm the artifact that comes back is the actual meal suggestion from your Nutrition Agent, not a generic response.
- If it fails: before you touch anything, look at where it failed. A rejected connection, a missing skill match, and a malformed Agent Card all fail differently โ that difference is the diagnostic information.
Part 4 โ Save your artifact (10 min)
- In a new note (or at the bottom of your workflow's sticky note in n8n), record:
Your final Agent Card JSON
The task you sent and the artifact you got back
One sentence: what's actually different about this, compared to adding "nutrition" as a tool on your Day 4 MCP server?
Agentic AI โ Week 1, Day 7
Optional Paths
If you finish early, see the Extension section below before asking your facilitator what to do next.
Agentic AI โ Week 1, Day 7
Success Criteria
You're done when:
- Your Nutrition Agent has a valid, complete Agent Card declaring one real skill.
- Your Workout Agent stand-in successfully sends a task via the A2A Client node and receives a completed task with a real artifact โ not an error, not a timeout.
- You can say, in one sentence, why this is architecturally different from what you built in Day 4.
A failed first attempt that you can diagnose (bad Agent Card, wrong endpoint, skill mismatch) is a legitimate outcome of this exercise โ you'll be asked about it in the debrief either way.
Agentic AI โ Week 1, Day 7
Extension (fast finishers)
Add a second skill to your Nutrition Agent โ but make it one it probably shouldn't have, like "medical advice for injury-related nutrition." Don't build the logic behind it; just declare it on the Agent Card. Then answer for yourself: if your Workout Agent could see that skill was available, should it be allowed to call it automatically? What would you need to add โ to either agent โ before the answer is yes? Hang onto your answer; it'll matter again in Day 8.
