feature-design

A guided method for defining a software feature before building it. It turns an initial idea into a short design brief by clarifying who needs it, what starts the work, and what success means.

In plain words
What is it for?
It helps plan product features, technical capabilities, and other changes through a small number of focused questions and structured decisions.
Why use it?
It reduces unclear requirements and exposes missing goals, limits, trade-offs, and unwanted outcomes early.

Command for Claude Code

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add commands/sageox/ox/feature-design
Clone the repo
git clone --depth 1 https://github.com/sageox/ox

Made for: Claude Code.

Per session 99 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 887 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00099 $0.00887
Opus 5 $0.00049 $0.00443
Sonnet 5 $0.00020 $0.00177
Haiku 4.5 $0.00010 $0.00089

Measured 2d ago against content hash 74de158377d6, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

feature-design scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.claude/commands/feature-design.md · 108 lines

How it starts

The opening of the file, as written. The whole thing — 108 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Feature Design

A skill for structured feature elicitation: ask the right questions to surface goals, constraints, and tradeoffs, then produce a concise design brief.

Phase 1 — Orientation (1–2 questions max)

Start with a single open question to get the user talking:

"What problem does this feature solve, and who runs into it?"

Let them answer freely. Extract from their response:

  • Actor: who is affected (user, operator, agent, system)
  • Trigger: what situation or pain prompts the need
  • Outcome: what changes if this works well

If either actor or outcome is still unclear after their first answer, ask one targeted follow-up. Don't ask more than two questions in Phase 1.

Phase 2 — Structured Elicitation

Once you have basic orientation, work through the following dimensions. Don't ask all at once — cluster 2–3 related questions per turn, adapt based on what the user has already said, and skip anything already answered.

Goals & Success

  • What does success look like? How would you know it's working?
  • Is there a metric, behavior change, or user outcome you're optimizing for?
  • Are there anti-goals — things this feature explicitly should not do?

Users & Context

  • Who uses this, and how often? (power users vs. occasional; human vs. agent)
  • What's the context of use — what are they doing right before and after?
  • Are there distinct user segments with different needs?

Constraints & Scope

  • What's the delivery pressure — prototype, MVP, or production-grade?
  • Are there technical, regulatory, or resource constraints to design around?
  • What's explicitly out of scope for now?

Tradeoffs & Risks

  • What's the biggest thing that could go wrong?
  • Are there competing approaches you're already considering?
  • What would you sacrifice to ship faster?

Dependencies & Fit

  • Does this touch existing systems, APIs, or data flows?
  • Are there other features or teams this needs to coordinate with?
  • Is there prior art — internal or external — worth learning from?

Read the full file on GitHub · 108 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 108 lines · 99 tokens per session scan A 74de158377d6

Subscribe to this mod's changes

feature-design is a command published in the GitHub repository sageox/ox (50 stars, last pushed 4d ago), licensed MIT. It adds 99 tokens to every session and 887 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.