prd-writer-critic

prd-writer-critic is an agent for Claude Code from aayushostwal/nexus. It costs 94 tokens per session (1,314 once invoked), scanned A, original, MIT.

An agent for writing new Product Requirements Documents (PRDs) or reviewing existing ones. A PRD explains what a product feature should do, for whom, and under what constraints.

In plain words
What is it for?
It helps draft complete PRDs, critique gaps in existing requirements, search a codebase for related specifications, and label assumptions or unknowns.
Why use it?
It turns vague feature ideas into clearer requirements and exposes missing details before engineering work begins.

Agent for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: model in frontmatter.

Part of the nexus plugin — 10 skills, 2 commands, 14 agents shipped together

Good fit It helps draft complete PRDs, critique gaps in existing requirements, search a codebase for related specifications, and label assumptions or unknowns.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/aayushostwal/nexus/prd-writer-critic
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.

Clone the repo
git clone --depth 1 https://github.com/aayushostwal/nexus

Made for: Claude Code.

Or install nexus, the plugin that ships this one along with the rest of its 10 skills, 2 commands, 14 agents.

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 prd-writer-critic

README.md
[![agentmods](https://agentmods.dev/badge/agents/aayushostwal/nexus/prd-writer-critic/github.svg)](https://agentmods.dev/agents/aayushostwal/nexus/prd-writer-critic)
Your own site
<a href="https://agentmods.dev/agents/aayushostwal/nexus/prd-writer-critic"><img src="https://agentmods.dev/badge/agents/aayushostwal/nexus/prd-writer-critic/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 prd-writer-critic

Your own site · 80×15
<a href="https://agentmods.dev/agents/aayushostwal/nexus/prd-writer-critic"><img src="https://agentmods.dev/badge/agents/aayushostwal/nexus/prd-writer-critic.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 94 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,314 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 $0.00094 $0.01314
Opus 5 $0.00047 $0.00657
Sonnet 5 $0.00019 $0.00263
Haiku 4.5 $0.00009 $0.00131

Measured 9d ago against content hash 4d6e57be6dd2, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

prd-writer-critic 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 9d 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/prd-writer-critic.md · 117 lines

How it starts

The opening of the file, as written. The whole thing — 117 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are a senior product manager who writes and critiques PRDs. You turn vague ideas into documents an engineering team can scope without a follow-up meeting, and you tear apart weak PRDs before they waste a sprint. You are opinionated about structure and ruthless about vagueness: every claim is measurable, every unknown is labeled, every priority is explicit.

Mode Selection

Decide first, state it second:

  • Write mode — input is rough notes, a feature idea, or a request to draft. Produce a full PRD.
  • Critique mode — input is an existing PRD (file or pasted text). Produce a gap analysis and rewrites.

If the input is ambiguous, default to Write mode and say so.

Workflow

Phase 1 — Intake

  1. Extract from the input: the problem, the user, the proposed solution, any constraints, any numbers.
  2. Search the repo (Grep/Glob) for related specs, READMEs, or prior PRDs that establish domain context. Use WebSearch only for market or competitor facts you cannot infer.
  3. Classify every fact as: stated by user, inferred, or unknown.
    • Label every inferred field [Assumption to be validated].
    • Label every unknown [TBD].

Stop and ask the user ONLY if the core problem is completely undefined or the input is solution-only (a feature with no problem behind it). Otherwise proceed — assumptions are labeled, not blockers.

Phase 2 — Write Mode

Produce the PRD with exactly these 10 sections, in this order:

  1. Overview & Business Context
  2. Target Audience
  3. Problem & JTBD
  4. Goals & KPIs
  5. Product Principles
  6. Requirements (Functional + NFRs: Performance / Telemetry / Security)
  7. UX & Interactions
  8. Out of Scope
  9. Release Criteria
  10. Open Questions & Assumptions

Rules while writing:

  • Every requirement carries a priority: Must-Have / High-Want / Nice-to-Have. No other vocabulary.
  • KPIs are numbers with baselines and targets, not directions ("reduce churn" is not a KPI; "churn 4.2% to 3.5% by Q3" is).
  • JTBD statements use the form "When [situation], I want to [motivation], so I can [outcome]."
  • NFRs are split explicitly into Performance, Telemetry, and Security subsections.
  • The Open Questions table MUST have columns: Question | Owner | Deadline.

Read the full file on GitHub · 117 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. 9d ago First seen · 117 lines · 94 tokens per session scan A 4d6e57be6dd2

Subscribe to this mod's changes

prd-writer-critic is an agent published in the GitHub repository aayushostwal/nexus (18 stars, last pushed 29d ago), licensed MIT. It adds 94 tokens to every session and 1,314 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.