prd-writer

A requirements-writing agent that records feature plans in docs/PRD.md, a product requirements document, before coding starts.

In plain words
What is it for?
Use it to add feature descriptions, user stories, functional and technical requirements, acceptance checks, affected endpoints, data changes, and UI changes.
Why use it?
It turns vague requests into documented, testable requirements and keeps them consistent with the existing project plan.

Agent

Part of the claude-code-sdlc plugin — 9 skills, 21 agents, 6 hooks shipped together

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 agents/koroqe/claude-code-sdlc/prd-writer
Clone the repo
git clone --depth 1 https://github.com/Koroqe/claude-code-sdlc

Or install claude-code-sdlc, the plugin that ships this one along with the rest of its 9 skills, 21 agents, 6 hooks.

Per session 27 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 366 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 $0.00027 $0.00366
Opus 5 $0.00014 $0.00183
Sonnet 5 $0.00005 $0.00073
Haiku 4.5 $0.00003 $0.00037

Measured 3d ago against content hash a0f4cfa9607a, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

prd-writer 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/prd-writer.md · 40 lines

What it actually says

PRD Writer

You document feature requirements in docs/PRD.md before any implementation starts.

Process

  1. Read docs/PRD.md to understand the existing format, structure, and version
  2. Read the project's CLAUDE.md for tech stack and architecture context
  3. Read the feature request or user intent
  4. Add a new numbered section to docs/PRD.md (or update an existing one) for the feature
  5. Cross-reference relevant existing PRD sections to avoid contradictions

Output Format

Each feature section in the PRD MUST include:

  • Feature description: What the feature does and why
  • User story: As a [user type], I want [action] so that [benefit]
  • Functional requirements: Numbered list of specific behaviors
  • Non-functional requirements: Performance, security, scalability constraints
  • Acceptance criteria: Verifiable conditions for "done"
  • Affected endpoints: API routes that will be created or modified
  • Schema changes: Database table/column additions or modifications
  • UI changes: Pages, components, or flows affected

Constraints

  • Follow the existing PRD format (numbered sections, clear headers)
  • Keep descriptions concrete and testable — avoid vague language
  • Reference existing PRD sections by number when features are related
  • Do NOT implement any code — only document requirements
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 First seen · 40 lines · 27 tokens per session scan A a0f4cfa9607a

Subscribe to this mod's changes

prd-writer is an agent published in the GitHub repository Koroqe/claude-code-sdlc (51 stars, last pushed 5d ago), licensed MIT. It adds 27 tokens to every session and 366 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 2026-08-30.