Method

The Gap Last method is what you do when something arrived, you did not get to rerun it, and a story is already forming. You can do this without an account or an agent. The skill and the CLI keep the same order. The formal name is constraint-first reconstruction. A working draft of the method paper is here if you want the longer argument.

Say what happened as tightly as the evidence allows, and mark how sure you are. Use what is already known, fully: the geometry, the timing, what the record can and cannot show. Name what is still unknown, as a question. Only then propose a cause, and only for the question you named. When better evidence arrives, expect the question to move, and let it.

The order exists so a thin cause does not aim the next warning system, or the next mitigation, at the wrong object. Someone will build those on whatever cause you write down.

Four lines

For a person with no tool running:

1. The what, as tightly as you can say it. Mark it.
2. One mechanism the geometry, timing, or record already eliminates.
3. The leftover gap, named as a question.
4. Whether how or "who caused it?" is even the right question yet.

One-screen

When you have one breath, say four things and stop:

1. What happened, and how sure you are.
2. Stories the evidence already eliminates.
3. What is still unknown, as questions.
4. Whether later evidence moved the question.

Do not smuggle a cause you have not yet allowed yourself.

The reconstruction

When you want the work to stay, you fill a file. Nine sections, that order only. A new explanation may stand only in a question you have already named.

1. Bound event. What happened, where, when, at what scale.
2. Fact layers. What you can settle, what is still provisional, what is open.
3. Causal chain. What started it, what carried it, who stood in its path, what anyone did after.
4. Hoop failures. Stories the traces already eliminate.
5. Named residual gaps. The leftover questions. The only places a new cause may stand.
6. Allowed hypotheses. Only those that answer a named leftover question.
7. Discriminating traces. What would settle a question if it arrived.
8. Remainder. What is still unknown, stated as a result.
9. Reconstruction log. If later evidence changed the object: old question, new question.

Template.

A flood, a death, a failed launch, a family story: each is a chain, and each link asks a different question. Early stories press those questions into one. The file keeps them apart.

The last section is the plaque on the fence. It says which gap this closed, how sure you were, and what evidence would move it, so the next person who finds what you built does not have to guess why it stands. That is the debt the Gap Last method owes Chesterton's Fence.

Stop questions

Use these in a conversation without running the whole file:

• What part of the chain is this claim about: the start, the carry, or who stood in the path?
• Has the evidence already eliminated it?
• Is this a leftover question, or leftover storytelling?
• Did new evidence move the object, and if so, what is the question now?
• Is this an inherited fence you are about to clear unread, or a new one you are about to build on a first noun?
• Are you treating the leftover you named as the last gap, or as the question you have now?

A shorter form: is that the what, or are you already on a how?