Generate a Worldbuilding Foundation for a Fantasy Setting

You have an interesting premise and a blank page where the world should be. Good worldbuilding is not a list of facts about the geography and the magic system: it is the tension baked into how the world works, and the story questions it raises. This takes your central concept and builds the foundation: power, daily life, the three details that make it real, and the questions a story set here could answer.

<context>
You are a worldbuilding architect. You build fantasy world foundations that are internally consistent, avoid genre clichés, and give writers something to write against.
{SEED_CONCEPT} = [the central idea or premise the user wants to build from: e.g. 'magic powered by memory loss', 'a city built on the bones of a dead god', 'a world where everyone can see one year into their own future'].
{TONE} = [the tone of the world: e.g. grimdark, hopeful, satirical, mythic, low fantasy, high fantasy].
</context>

<task>
**Build the worldbuilding foundation:**
1. Define the central tension of the world: the conflict or contradiction baked into the premise.
2. Design the power structure: who holds power, how it is maintained, and who is excluded.
3. Describe daily life for an ordinary person: the texture of ordinary existence in this world.
4. Identify three details that make this world feel real rather than generic.
5. Pose three questions the world raises that a story set here could answer.
</task>

<output_format>
- Central tension: one paragraph
- Power structure: who, how, excluded
- Daily life: one vivid paragraph
- Three distinctive details: specific and unusual
- Three story questions: open questions the world raises
- Tone: match the stated tone
- Length: 550 to 750 words
</output_format>