codexspec:spec-to-design

codexspec:spec-to-design is a skill for Claude Code, Codex from Zts0hg/codexspec. It costs 23 tokens per session (1,296 once invoked), scanned A, original, MIT.

A skill for turning an approved specification into a design document. A specification describes the agreed needs, while a design explains the system's structure and interfaces.

In plain words
What is it for?
Use it to define components, interfaces, and key technical decisions for a feature.
Why use it?
It connects agreed requirements to concrete architecture and design decisions without mixing in the later build plan.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: installed under .agents/ (shared by several agents).

Good fit Use it to define components, interfaces, and key technical decisions for a…

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Install with agentmods
npx agentmods add skills/zts0hg/codexspec/codexspec-spec-to-design
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.

Any agent
npx skills add Zts0hg/codexspec --skill codexspec-spec-to-design
Clone the repo
git clone --depth 1 https://github.com/Zts0hg/codexspec

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for codexspec:spec-to-design

README.md
[![agentmods](https://agentmods.dev/badge/skills/zts0hg/codexspec/codexspec-spec-to-design.svg)](https://agentmods.dev/skills/zts0hg/codexspec/codexspec-spec-to-design)
Your own site
<a href="https://agentmods.dev/skills/zts0hg/codexspec/codexspec-spec-to-design"><img src="https://agentmods.dev/badge/skills/zts0hg/codexspec/codexspec-spec-to-design.svg" alt="Measured on agentmods" height="20"></a>
Per session 23 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,296 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 5.1 $0.00023 $0.01296
Opus 5 $0.00012 $0.00648
Sonnet 5 $0.00005 $0.00259
Haiku 4.5 $0.00002 $0.00130

Measured 3d ago against content hash 029705517630, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

codexspec:spec-to-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 3d 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.

.agents/skills/codexspec-spec-to-design/SKILL.md · 119 lines

How it starts

The opening of the file, as written. The whole thing — 119 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Specification to Design Converter

Language Preference

Read .codexspec/config.yml. Two independent language controls apply (each falls back to language.output, then English):

  • Interaction language (language.interaction): language for all conversation with the user — questions, explanations, status messages, and codexspec CLI terminal output.
  • Document language (language.document): language for generated artifact files (requirements/spec/plan/tasks).

Converse in the interaction language and author artifacts in the document language. Apply the project's translation standard to both: translate by meaning (not word-for-word), keep English for terms with no good native equivalent, and write as if originally in that language.

User Input

the text after the $codexspec:spec-to-design skill mention

Role

Act as a constrained system designer. Define what the system is — architecture, components, interfaces, and key design decisions — that realizes the specification, while preserving confirmed user intent. Do not plan how to build it in phases; that belongs to the downstream plan stage.

Feature Resolution

Use an explicit path first, then the current branch. If neither uniquely identifies a feature, ask the user to select one. Never silently select the latest feature.

Read:

  • requirements.md
  • spec.md
  • .codexspec/memory/constitution.md when present
  • Relevant repository files needed to verify existing patterns and constraints

Legacy compatibility: if requirements.md is absent, treat spec.md as the temporary highest authority and disclose that original-discussion fidelity cannot be checked.

Authority and Stop Conditions

Authority order:

  1. Confirmed requirements.md
  2. spec.md
  3. Constitution and verified repository facts
  4. Design-level technical decisions
  5. General best practices

Before designing, verify that spec.md covers the confirmed requirements. Stop if it omits, contradicts, or silently expands them.

Read the full file on GitHub · 119 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. 3d ago Changed · +7 lines · +5 tokens per session 029705517630
  2. 7d ago First seen · 112 lines · 18 tokens per session scan A fd2a4c8c50ab

Subscribe to this mod's changes

codexspec:spec-to-design is a skill published in the GitHub repository Zts0hg/codexspec (5 stars, last pushed today), licensed MIT. It adds 23 tokens to every session and 1,296 once invoked, about $0.0001 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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