planning — invest
INVEST — the story shape diagnostic
The map shows what stories exist and how they cluster into releases. The shaping artifacts — wireframes, sequence diagrams, schemas — show what each story actually contains. With both visible, the team can ask a different question: are these stories the right shape?
The standard heuristic for story shape is INVEST: Independent, Negotiable, Valuable, Estimable, Small, Testable. Most teams know it as a checklist for writing stories. The deeper use is as a diagnostic — applied against the map and the shaping artifacts, to find stories that need to split, merge, or sharpen before they enter amigos.
| Independent | Can this story flow on its own, or does it need another story to ship first? Two stories that can't be pulled separately are one story pretending to be two — merge them, or extract the dependency into a third story that unblocks both. |
| Negotiable | Is the story a fixed contract, or can the trio still adjust it as amigos surfaces edge cases? A story locked at the wireframe level is not yet ready to flow — amigos exists to refine it, and a story that can't be refined isn't a story, it's a specification. |
| Valuable | Does this story, on its own, change something for the person? If the answer is "only when paired with three others," the story is part of a slice but not a discrete unit of value — that's fine for shaping, but it means the slice is the unit of value, not this story alone. |
| Estimable | Can the developer give a rough sense of how big this is? Not a story-point estimate — a sense of whether it's a day, a few days, or a week. If even that's unclear, shaping isn't done. |
| Small | Will this story flow through development in a week or less? If it's bigger, it should split. A story that takes three weeks is not a story — it's an Epic that hasn't been broken down. |
| Testable | Can the done condition be checked? If the criterion is "feels better" or "is more intuitive," the story isn't testable yet — sharpen the criterion before amigos. |