We got up at 5 a.m. to head to Huanghua, where Liuliu’s dad drove us to visit her at her grandma’s place. Hamer and Liuliu were clearly thrilled to see each other, though they tried to play it cool. I was unsure about driving back to Beijing alone and hoped Liuliu’s dad could take the car while we returned by train.

Lunch was a feast—seafood, lamb spine hotpot, and shrimp paste flatbread—that left me full well into the evening. We strolled through Xinyulou in the afternoon, and later, the four of us played mahjong until past 11. Afterward, Zhu Jian took me visit a local bathhouse for a soak and steam, spending the night there.

Tonight, we attended our first performance at the China National Opera House—a symphony and ballet set to The Yellow River. The music, staging, and dancing were breathtaking, and we left wanting to see it all over again.

Since our e-bike couldn’t fit four, I planned to run home—but Hamer wanted to join. We waited backstage, caught glimpses of the dancers leaving, then walked home together, snacking on frozen grapes from 7-Eleven. We held hands, laughed, and skipped until she got tired. At Chuangshan Liquor Bar, we stopped for skewers and beer to rest.

After dropping Hamer off at school this morning, I grabbed a big breakfast to share at home—more than we could finish.

Most of the day was spent diving into the MCP C# SDK. While reviewing the official samples, I spotted a bug I initially planned to fix, only to find someone had already submitted a PR—so I added a supporting comment instead. I also spent time exploring how to integrate MCP with the Earth project but realized it’s not easy to integrate directly.

In the evening, After shopping, we visited a print shop to print photos for Hamer.

Hello, April.

This morning, I woke up early and joined Hamer for a morning run. We ran and walked around 3 kilometers together—it was a joyful experience. On our walk back, she said the day felt like a weekend without school.

At work, I learned I’ll be taking over the lead of a project. It didn’t hit me until I was added to the group, making me realize this new responsibility.

In the evening, I grabbed some draft beer and skewers on a whim, and Xiaoyan couldn’t resist nibbling despite being full.

There was a moment of misunderstanding with Hamer’s homework, where I was adamant I was right, but later discovered she was correct. I realized I need to listen to her more and not always assume my perspective is the right one.

We also got our registration confirmed for the parent-child run at a local Half Marathon. Looking forward to it!

I spent the day optimizing the MCP server for ArcGIS Earth Automation API and troubleshooting data issues. Recorded demos using Claude as a client, which impressively handled polygon drawing and undo-delete commands.

Evening brought news I wasn’t selected for the Beijing Half Marathon. After dinner with Xiaoyan, I helped Hamer with homework and fixed her alarm. When she wanted to join my run but hesitated, we planned a morning run for April 1st instead.

Today was a leisurely Sunday that began with sleeping in until Hamer asked for help reading her textbook. Initially, I suggested she practice independently, which led her to seek Grandma’s assistance before proudly returning to demonstrate her progress.

My coffee experiment failed due to using espresso beans and too-fine grounds for pour-over brewing. At noon, we visited the Beijing Minsheng Art Museum for “The Origin of Civilization” exhibition, where LEGO recreations of archaeological sites and a bronze figure installation particularly impressed me.

After lunch at Sunrise Ramen in its new Wangjing location, we explored 798 Art District. At Berry Bean café, Hamer bonded with a dog named Huahua while I admired specialty bikes. The day concluded at Tiaohai Bar, where we unexpectedly stayed for a dance concert featuring memorable performances by SkyChildren, NoGender, and a duet by Quqi and Erhan.

This morning, Hamer and I used GPT-4o to enhance one of her drawings—she was amazed, though she noticed its text recognition could be better. After breakfast at Xiaoguan Market, we met her classmate. Hamer didn’t join the group play, preferring one-on-one time, but still enjoyed observing.

The wind on our way back was intense, and Xiaoyan later got her braces replaced. In the afternoon, I played in a football match with the CUGB alumni team after a four-year break—starting as goalkeeper and easing back into the game.

Since neither of us could take Hamer to dance, Grandma stepped in. Last night, Hamer cried about it, but Xiaoyan had a clever solution: Grandma would take her to class, and later they’d go to The Box to visit Miniso.

In the evening, we all played doubles at a new badminton gym, then grabbed barbecue on the way home—a relaxing end to a full day.

Today, I continued working hands-on with the MCP server, this time using the ArcGIS Earth Automation API as the application scenario. I used Cursor together with Claude 3.7 Sonnet, referencing the official Model Context Protocol servers’ Python SDK to carry out some Vibe Coding. By the end of the workday, I had successfully run through the core workflow. There’s still some polishing to do before submission, but it’s coming together nicely. I tested the setup using the MCP Inspector, which worked quite well. Toward the end of the day, I switched back to using Claude as the MCP Client for another round of testing. It was genuinely exciting to see Claude follow my instructions, call various tools, and interact with Earth—I could hardly wait to complete the whole workflow!

As usual, I went to the gym at noon. I didn’t work out much, but the key thing is maintaining the habit.

In the evening, it got really cold. I had originally planned to go pick up Xiaoyan from Sanlitun, but halfway there, I felt frozen and asked her to take the subway instead—I met her at the station. After dinner, Hamer continued putting up English conversation stickers with me. She had even called me after school to remind me to come home early so we could do it together. I had intended to watch a movie afterward, but Hamer came running over, asking to join. In the end, we watched the animated film Goldie together.

Today, I was completely immersed in developing an MCP server for ArcGIS Location Services, to the point of practically skipping meals and breaks. By the end of the workday, I had finally built a simple, functional version. In the evening, I also tried submitting it to Smithery, though I still need to figure out how to properly use the deployed server—something I’ll dig into later.

Throughout the development process, I used uv to manage the Python project. The implementation was based on the ArcGIS Services Postman Collection, and I relied heavily on conversations with Claude and the Edit Mode in Cursor to guide my work. One of the trickiest parts was that the Postman Collection didn’t provide complete parameter details to the LLM, which led to a lot of misconfigured requests that took quite a bit of time to debug.

I used Claude Desktop as an MCP Client to test the server and found that using conversational prompts to drive the LLM for testing was a surprisingly fun experience. However, debugging wasn’t the most convenient, so I’m planning to try out the MCP Inspector to streamline the process going forward.

This morning, I also joined the CUGB Beijing Alumni Soccer Team group chat. The admin was super welcoming and gave me a great intro to the team, along with some useful info. I signed up to play in a match this Saturday afternoon—looking forward to getting out on the field and meeting everyone.

In the evening, the On Running shoes Xiaoyan ordered for me arrived. The fit was perfect, and I really liked how they felt—so much so that I kept walking around the house in them all night. Later on, Hamer and I put up some immersive English-language stickers around the house for speaking practice. It was a fun little parent-child activity.

I was tired in the afternoon from poor sleep and felt it during badminton, though I did test Xiaoyan’s new racket and liked it.

I also published my half-marathon training plans on GitHub Gist, upgraded Claude to Pro, and used it as an MCP Client—its power impressed me.

In the evening, Hamer and I shopped at Hema after dinner.