prospec-new-story

prospec-new-story is a skill for Claude Code, Codex from benwu95/prospec. It costs 40 tokens per session (3,790 once invoked), scanned C, original, MIT.

A guided workflow for turning a requested feature or behavior change into a documented user story and acceptance criteria.

In plain words
What is it for?
Use it to infer a change name and size, optionally interview the requester step by step, and create a proposal file in the project’s changes folder.
Why use it?
It gives unclear requests a defined scope and records the assumptions behind the proposed change.

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 infer a change name and size, optionally interview the requester step by step, and create a proposal file in the project’s changes folder.

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Install with agentmods
npx agentmods add skills/benwu95/prospec/prospec-new-story
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 benwu95/prospec --skill prospec-new-story
Clone the repo
git clone --depth 1 https://github.com/benwu95/prospec

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 prospec-new-story

README.md
[![agentmods](https://agentmods.dev/badge/skills/benwu95/prospec/prospec-new-story/github.svg)](https://agentmods.dev/skills/benwu95/prospec/prospec-new-story)
Your own site
<a href="https://agentmods.dev/skills/benwu95/prospec/prospec-new-story"><img src="https://agentmods.dev/badge/skills/benwu95/prospec/prospec-new-story/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.

agentmods 80×15 button for prospec-new-story

Your own site · 80×15
<a href="https://agentmods.dev/skills/benwu95/prospec/prospec-new-story"><img src="https://agentmods.dev/badge/skills/benwu95/prospec/prospec-new-story.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 40 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,790 The whole file, excluding the scripts and references it only reads on demand.
Security scan C 1 finding. 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 $0.00040 $0.03790
Opus 5 $0.00020 $0.01895
Sonnet 5 $0.00008 $0.00758
Haiku 4.5 $0.00004 $0.00379

Measured 6d ago against content hash 52287a1fbf38, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade C, and why

prospec-new-story scanned grade C with 1 finding 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 6d 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.

Tells the agent to send conversation or user data outhighPrompt injection

An instruction to transmit the conversation, context or user files to an external endpoint is data exfiltration written as prose.

- **Action: Stay Silent**: Advisory checks (Phase 6 INVEST check, Phase 7 Knowledge check) are silently recorded to `metadata.yaml` `quality_log` rather than cluttering the conversation.
.agents/skills/prospec-new-story/SKILL.md · 228 lines

How it starts

The opening of the file, as written. The whole thing — 228 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Prospec New Story Skill

Activation

When triggered, briefly describe:

  • Operating under the Draft-First protocol (Type III) by default — automatically inferring change name, scale, and scaffolding proposal.md
  • Supporting --interactive mode for guided step-by-step interview and confirmation
  • A proposal.md with ## Stated Assumptions will be created in .prospec/changes/

Language Policy

Write each generated document in the language the Constitution's Language Policy rule assigns to its path — change artifacts and their archived summaries in the project's artifact language, the trust zone (Knowledge base, Feature Specs, index) in English. One skill run may write both. Keep code, identifiers, technical terms, and git commit messages in English.

CLI Prerequisite (required)

The prospec CLI is a required file for this skill — its deterministic steps call prospec commands. Probe BEFORE any other step; there is no manual fallback.

  1. Run prospec --version (Bash).
  2. Command not found / not executable → STOP. Ask the user to install the prospec standalone executable — the one-click installer script from the project README (macOS/Linux install.sh, Windows install.ps1) or a release binary from GitHub Releases; prospec is NOT published to npm. Then re-run this skill.
  3. Version older than 2.1.0 → STOP. Report the installed vs required version and ask the user to upgrade, then re-run this skill.

Hand-executing a CLI-owned mutation is NEVER the fallback — that re-introduces the nondeterministic serialization this contract exists to remove.

Startup Loading

  1. [STABLE] Read prospec/CONSTITUTION.md — prepare Constitution check
  2. [STABLE] MANDATORY — Read references/proposal-format.md for proposal.md format specification
  3. [DYNAMIC] Read references/metadata-format.md on demand for metadata.yaml FIELD SEMANTICS only — the file itself is CLI-written (prospec change story / change scale / change log), never hand-serialized
  4. [DYNAMIC] Read prospec/index.md — identify related modules by matching proposal keywords against module keywords field
  5. [DYNAMIC] Read prospec/specs/features/ — check existing feature specs for context

Read the full file on GitHub · 228 lines

Files

What ships with it

2 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.

  1. 6d ago Changed 52287a1fbf38
  2. 10d ago First seen · 228 lines · 40 tokens per session scan C f4f8b9942eb4

Subscribe to this mod's changes

prospec-new-story is a skill published in the GitHub repository benwu95/prospec (5 stars, last pushed 3d ago), licensed MIT. It adds 40 tokens to every session and 3,790 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it C with 1 finding (tells the agent to send conversation or user data out). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.