AI refuses Venn diagram in mermaid, author hand-draws it

The starting point is the ikigai four-circle diagram, which the author assumed would be quick to reproduce in mermaid now that AI can write code. That assumption failed twice: the AI first declined the diagram type outright, and when pushed with an image and instructions to use a venn diagram, it produced something shaped like a diagram but with unusable text. Beyond the model's behavior, the author points to mermaid itself — the automatic layout recalculates each run, so with four circles and labels the output drifts and cannot be controlled.

The author's takeaway is not a tool review but a skill argument. Getting a usable result required specifying what could be omitted, which characters were allowed, and where text should be trimmed — in other words, precise 言語化 of the expected output. From that, the piece proposes a format: a problem statement with sample answers that separate the parts allowed to vary from the relationships that must not change, such as the rule that what you love and what you are paid for together constitute a vocation.

The author frames this as a playful exercise rather than a product critique, inviting readers to post their own prompts in the comments, and ties it to a daily workflow of generating code — control over that output, the author suggests, is what the language-training question is meant to build.