Fix XMTP agent getting started guide Step 4

[wamimi]

What changed? Why?

This PR fixes critical issues in Step 4 of the XMTP agent getting started guide that prevented users from successfully creating and running their first agent.

While following the tutorial, I encountered multiple blocking errors that made it impossible to complete the guide.

---

Issue 1: Deprecated getTestUrl import causing SyntaxError

Problem:
The documentation shows this import:

import { Agent, getTestUrl } from "@xmtp/agent-sdk";

Error encountered:

SyntaxError: The requested module '@xmtp/agent-sdk' does not provide an export named 'getTestUrl'

Root cause:
The getTestUrl export has been removed or deprecated from the @xmtp/agent-sdk package.

Solution:
Removed the deprecated import and simplified the start event logging to only show the agent address.

---

Issue 2: Missing environment variable loading causing XMTP_WALLET_KEY error

Problem:
When running the agent code from the documentation, it immediately failed with:

AgentError: XMTP_WALLET_KEY env is not in hex (0x) format.
    at Agent.createFromEnv (/node_modules/@xmtp/agent-sdk/src/core/Agent.ts:190:13)

Root cause:
The .env file existed with correct values, but the code wasn’t loading environment variables before calling Agent.createFromEnv().

Solution:
Added import "dotenv/config"; at the top of the code to load environment variables before the agent initializes.

---

Issue 3: Unclear file location for agent code

Problem:
Step 4 showed the agent code but never explicitly stated where to create the file. I was left guessing whether to:

• Create it in the examples folder
• Create it in the root
• Replace an existing file

Solution:
Added explicit instructions to create index.ts in the project root using:

touch index.ts

---

Issue 4: Incorrect run command

Problem:
The documentation mentioned npm run dev, but this runs the default example (xmtp-gm) from package.json, not the developer's newly created agent.

Solution:
Updated instructions to use:

npx tsx --watch index.ts

which directly runs the dev's agent file.

---

Issue 5: Adding testing instructions

Problem:
After fixing the above issues, the agent runs successfully but only outputs:

Agent is online at address: 0x4a86dfa0ad31801256dd5f8bdf95b3ea5bbe2ba9

There were no clickable links or instructions on how to interact with the agent.

Solution:
Added comprehensive testing instructions:

1. Copy the agent address from terminal
2. Go to xmtp.chat
3. Connect wallet
4. Switch to Dev environment
5. Start new conversation with the agent address
6. Send a message and verify the response

---

**Added explanatory comments to code **

Added detailed inline comments explaining:

• Why dotenv/config is needed
• What createFromEnv does
• How the event listeners work
• What each parameter means

Added

• 💡 Tip callout explaining the critical importance of import "dotenv/config".
• Clear file creation instructions (touch index.ts in root).
• Correct run command (npx tsx --watch index.ts).
• Step-by-step testing instructions for xmtp.chat.
• Tip about environment matching (dev vs production).
• Detailed Inline code comments for more clarity.

---

Removed

• Deprecated getTestUrl import and usage.
• Confusing sections about the examples folder workflow.

---

Notes to Reviewers

These changes address real, blocking errors that prevented me from completing the tutorial.
Every change is based on actual errors encountered during testing:
The updated code has been tested end-to-end and works successfully.
I also spun up the documentation site locally to verify formatting and that the Tip callouts render correctly.

---

How has it been tested?

Started from a fresh clone of the xmtp-agent-examples repository
Verified agent started without errors
Sent test messages and confirmed agent responded with
"Hello from my XMTP Agent! 👋"
Spun up documentation site locally

[cb-heimdall]

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[humanagent]

@wamimi Thanks for the update! we have a pending PR a well, i think it's about to merge #435

[wamimi]

@wamimi Thanks for the update! we have a pending PR a well, i think it's about to merge #435

Thanks for letting me know! I see that PR #435 has been merged. I've opened a new PR (#610) that builds on top of those changes and addresses some additional flow issues I discovered while testing the guide. I'll close this PR now since #435 is merged. Looking forward to your feedback on #610!