Spec

Produce a spec (you may know this document as a PRD) from the current conversation and codebase understanding. Synthesize what you already know — the interview, if any, already happened (/grill-me).

Process

1. Explore the repo to understand the current state of the codebase, if you haven't already.

Use the project's domain vocabulary throughout the spec.

1. Search docs/solutions/ and existing docs/specs/ for learnings that bear on this feature — root causes, gotchas, approaches that failed before, decisions already made.

Fold whatever applies into the spec's decisions.

1. Propose the test seams — the places /implement will drive TDD (seam vocabulary: the codebase-design skill).

Prefer existing seams to new ones; place any new seam at the highest point you can. The fewer seams across the codebase, the better — the ideal number is one.

Check the seams with the user before writing the spec: approving them now, while the decisions are fresh, lets implementation test at them later without relitigating the design.

1. Write the spec to docs/specs/.md (kebab-case feature slug) using the template below.

Problem Statement

The problem that the user is facing, from the user's perspective.

Solution

The solution to the problem, from the user's perspective.

User Stories

A LONG, numbered list of user stories. Each user story should be in the format of:

1. As an , I want a , so that

1. As a mobile bank customer, I want to see balance on my accounts, so that I can make better informed decisions about my spending

This list of user stories should be extremely extensive and cover all aspects of the feature.

Implementation Decisions

A list of implementation decisions that were made. This can include:

• The modules that will be built/modified
• The interfaces of those modules that will be modified
• Technical clarifications from the developer
• Architectural decisions
• Schema changes
• API contracts
• Specific interactions

Do NOT include specific file paths or code snippets. They may end up being outdated very quickly.

Exception: if a prototype produced a snippet that encodes a decision more precisely than prose can (state machine, reducer, schema, type shape), inline it within the relevant decision and note briefly that it came from a prototype. Trim to the decision-rich parts — not a working demo, just the important bits.

Test Seams

The seams the user approved in step 3 — where TDD will bite during implementation. For each seam: the interface under test, what behavior the tests will verify through it, and prior art (similar tests in the codebase).

Out of Scope

A description of the things that are out of scope for this spec.

Further Notes

Any further notes about the feature.

Spec written → next: /tickets if the work spans multiple sessions or context windows, else /implement — in a fresh context either way.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: toverux
• Source: toverux/grimoire
• License: MIT

Install and usage instructions live in the source repository linked above.