What is productspec-authoring?

A writing and validation guide for ProductSpec files, Markdown documents that record a feature's intended product decisions before tickets, plans, and code.

Use it to create a new product specification, convert a product requirements document into the required format, or validate and record changes to a specification.

It gives teams a consistent, machine-checkable place to agree on the problem, scope, acceptance criteria, and measures of success.

productspec-authoring — Skill by gokulrajaram/ProductSpec

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 gokulrajaram/ProductSpec --skill productspec-authoring

Clone the repo

git clone --depth 1 https://github.com/gokulrajaram/ProductSpec

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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/gokulrajaram/productspec/productspec-authoring/github.svg)](https://agentmods.dev/skills/gokulrajaram/productspec/productspec-authoring)

Your own site

<a href="https://agentmods.dev/skills/gokulrajaram/productspec/productspec-authoring"><img src="https://agentmods.dev/badge/skills/gokulrajaram/productspec/productspec-authoring/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/gokulrajaram/productspec/productspec-authoring"><img src="https://agentmods.dev/badge/skills/gokulrajaram/productspec/productspec-authoring.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 90 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 839 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. Third-party audits

NVIDIA SkillSpector pass 7 Sept 2026

How audits are shown

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.

Model	Per session	Once invoked
Fable 5.1	$0.00090	$0.00839
Opus 5.5	$0.00036	$0.00336
Sonnet 5.5	$0.00018	$0.00168
Haiku 4.5	$0.00009	$0.00084

Measured 2mo ago against content hash 25fb8a41d19f, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

productspec-authoring 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 2mo 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/productspec-authoring/SKILL.md · 45 lines

How it starts

The opening of the file, as written. The whole thing — 45 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Authoring ProductSpec Files

ProductSpec is a Markdown format for the product decision that comes before tickets, engineering plans, and code. One file per feature holds the committed intent.

This skill covers producing that file. Reading a finished spec and building against it is a different job, and the productspec skill covers it. This skill ends when the file validates.

Always true

Files use the extension .product-spec.md: YAML frontmatter between --- markers, then ## Section headings.
Six sections are mandatory, in order: problem, hypothesis, product_summary, scope, acceptance_criteria, success_metrics.
Headings match case- and separator-insensitively. ## Acceptance Criteria and ## acceptance_criteria are the same section. Title case is the convention.
Frontmatter requires spec_format_version: "0.1", title, artifact_type (hypothesis | prd | openspec_proposal), author, created_at, updated_at. Optional: spec_revision, linked_github_repo, applies_to, custom_sections, tool_metadata.
acceptance_criteria and success_metrics each carry a required fenced block. Prose alone fails validation. Structured scope, AI evals, and related artifacts are optional.
Structured items carry durable ids: AC-<number>, SM-<number>, EVAL-<number>. Other documents cite them.
AI evals live inside ## Acceptance Criteria, never in a section of their own. Related artifacts live inside ## Related Artifacts.
Validate any file with: npm exec --yes --package @productspec/parser -- productspec validate <file> (--yes suppresses npm's interactive install prompt, which hangs CI and non-interactive agents).
The full normative definition is SPEC.md in the ProductSpec repository: https://github.com/gokulrajaram/ProductSpec/blob/main/SPEC.md. When this skill and SPEC.md disagree, SPEC.md wins.

Pick the task, read one reference

Task	Read
Write a new spec from scratch	references/authoring.md
Validate files and fix errors	references/validating.md
Convert an existing PRD or feature doc	references/converting.md
Record drift, revisions, and outcomes	references/decision-trace.md

Read the full file on GitHub · 45 lines

Files

What ships with it

4 files 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.

2mo ago First seen · 45 lines · 90 tokens per session scan A 25fb8a41d19f

Subscribe to this mod's changes

productspec-authoring is a skill published in the GitHub repository gokulrajaram/ProductSpec (317 stars, last pushed 3mo ago), licensed MIT. It adds 90 tokens to every session and 839 once invoked, about $0.0004 per session on Opus 5.5. 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.

OpenSpec Planning Writing and docs ai-agents developer-tools markdown prd product-management

productspec-authoring next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
productspec-authoringgokulrajaram/ProductSpec	Skill	317	3mo ago	MIT	A	90	Claude Code, Codex
prd-taskmasteranombyte93/prd-taskmaster	Skill	608	2d ago	MIT	A	93	Claude Code
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