design-document

A structured document that records agreed technical decisions before implementation begins.

In plain words
What is it for?
Writing software designs, specifications, and implementation-ready technical plans.
Why use it?
It turns scattered requirements and brainstorming into one clear reference for planning and coding.

Skill for Claude CodeCodex

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 skills/uta2000/feature-flow/design-document
Any agent
npx skills add uta2000/feature-flow --skill design-document
Clone the repo
git clone --depth 1 https://github.com/uta2000/feature-flow

Made for: Claude Code, Codex.

Per session 61 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 6,447 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 $0.00061 $0.06447
Opus 5 $0.00030 $0.03223
Sonnet 5 $0.00012 $0.01289
Haiku 4.5 $0.00006 $0.00645

Measured 2d ago against content hash a5d42aa67d3d, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

design-document 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.

skills/design-document/SKILL.md · 501 lines

How it starts

The opening of the file, as written. The whole thing — 501 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Design Document

Turn brainstorming decisions into a structured, implementable design document. The document serves as the single source of truth between brainstorming and implementation planning.

Announce at start: "Writing design document to capture the agreed design before implementation."

When to Use

  • After brainstorming a feature (decisions have been made)
  • When the user has a clear idea of what to build and needs it documented
  • Before writing an implementation plan
  • When translating requirements into technical design

Optional Args (used when invoked from orchestrator dispatch)

When invoked as a Pattern B consolidator subagent (per #251), the orchestrator passes these arguments so the skill can skip the hoisted-fanout step and write its structured return contract back to the lifecycle's in-progress state file:

  • findings_path: <absolute-path-to-findings-json> — when set, the skill skips Step 1's Explore-agent dispatch and reads the pre-fetched findings from this JSON file instead. The file contains the consolidated {schema, pipeline, ui, format, code, ...} findings produced by the orchestrator-side parallel fanout. Format: {"agents": [{"area": string, "findings": string[]}, ...]}.
  • write_contract_to: <absolute-path-to-in-progress-yml> — when set, writes the return contract to phase_summaries.<phase_id>.return_contract in that YAML file after Step 4 (issue body merge) completes (see Step 8 below).
  • phase_id: <bucket-name> — identifies which phase_summaries bucket to write into. Must be one of the four fixed buckets: brainstorm, design, plan, or implementation. If absent when write_contract_to is set, defaults to design (the bucket that contains the design-document lifecycle step). Do not confuse phase_id with the contract's own phase fieldphase_id is the bucket key (design); the contract's phase field is the lifecycle step name (design-document) per #251's locked spec.

All three args are optional. If findings_path is absent, Step 1 dispatches Explore agents as before. If write_contract_to is absent, Step 8 is skipped — the skill behaves identically to its inline-invocation form.

Read the full file on GitHub · 501 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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 · 501 lines · 61 tokens per session scan A a5d42aa67d3d

Subscribe to this mod's changes

design-document is a skill published in the GitHub repository uta2000/feature-flow (4 stars, last pushed 1mo ago), licensed MIT. It adds 61 tokens to every session and 6,447 once invoked, about $0.0003 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 2026-08-31.

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