specification-agent

specification-agent is an agent for Cursor from openplanr/planr-pipeline. It costs 0 tokens per session (2,504 once invoked), scanned A, a copy of specification-agent, MIT.

A specification-writing agent that turns a feature into user stories and development tasks. It can write these documents in either the project’s standard layout or a specification-based layout.

In plain words
What is it for?
Use it in the /plan workflow to create stories and tasks for a named feature, with optional database or design inputs.
Why use it?
It gives developers a detailed, organized description of what to build before implementation starts.

Agent for Cursor

Installs and runs on its own, but its text points at files inside its plugin — anything it tells you to read at a ${CLAUDE_PLUGIN_ROOT} path is only there once the plugin is installed. Installing the plugin gets both.

Part of the planr-pipeline plugin — 8 skills, 10 commands, 9 agents, 1 hook 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/openplanr/planr-pipeline/specification-agent
Clone the repo
git clone --depth 1 https://github.com/openplanr/planr-pipeline

Made for: Cursor.

Or install planr-pipeline, the plugin that ships this one along with the rest of its 8 skills, 10 commands, 9 agents, 1 hook.

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 specification-agent

README.md
[![agentmods](https://agentmods.dev/badge/agents/openplanr/planr-pipeline/specification-agent.svg)](https://agentmods.dev/agents/openplanr/planr-pipeline/specification-agent)
Your own site
<a href="https://agentmods.dev/agents/openplanr/planr-pipeline/specification-agent"><img src="https://agentmods.dev/badge/agents/openplanr/planr-pipeline/specification-agent.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 2,504 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 100% copy Near-identical to another mod 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 $0.00000 $0.02504
Opus 5 $0.00000 $0.01252
Sonnet 5 $0.00000 $0.00501
Haiku 4.5 $0.00000 $0.00250

Measured 4d ago against content hash d8521d5d8be3, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

specification-agent 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 4d 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.

Origin

This is a copy

100% identical to specification-agent — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.cursor/rules/agents/specification-agent.md · 283 lines

How it starts

The opening of the file, as written. The whole thing — 283 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Cursor adapter — synthesized from planr-pipeline. Agent role system prompt (body-only). Used by /cursor/rules/planr-pipeline.mdc for Composer subagent dispatch. Source: planr-pipeline/agents/specification-agent.md (frontmatter stripped — Cursor uses different permission model; restrictions documented in the role body and the master rule).

Specification Agent

Phase: Step 1 — PO Phase (terminal agent in the PO chain) Trigger: Invoked by /planr-pipeline:plan after upstream agents complete Chained after: db-agent (if DatabaseType configured) → designer-agent (if PNGs present) Input feature name: Passed by /planr-pipeline:plan as $ARGUMENTS (e.g. auth → operates on feat-auth)

Path Resolution (NEW in pipeline v0.3.0)

This agent runs in one of two modes, determined by the orchestrator command (/plan):

  • Default mode: Output goes to output/feats/feat-$ARGUMENTS/us-{N}/{us-{N}.md, tasks/task-{M}.md}
  • Spec-driven mode: Output goes to .planr/specs/SPEC-NNN-${ARGUMENTS}/{stories/US-NNN-{slug}.md, tasks/T-NNN-{slug}.md} (slug-based filenames; flat tasks/ directory; per-spec ID scoping)

The orchestrator passes MODE = "spec-driven" and SPEC_DIR in the invocation context when planr's .planr/config.json declares spec mode. In spec mode, US-NNN and T-NNN IDs are SCOPED TO THE PARENT SPEC (not project-globally unique). When you write artifacts, use the spec-mode paths and filenames; otherwise use the default-mode paths. Schema content (frontmatter + body) is identical in both modes.


Purpose

The Specification Agent is the core decomposition engine of the PO Phase. It reads the functional spec, the design spec (if present), and the tech stack, then produces the full feature arborescence: User Stories + Tasks.

This agent determines the task count per US:

  • No PNG → 1 task per US (technical task only)
  • PNG present → 2 tasks per US (task-1: UI, task-2: Tech)
  • Never more than 2 tasks per US

Read the full file on GitHub · 283 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. 4d ago First seen · 283 lines · 0 tokens per session scan A d8521d5d8be3

Subscribe to this mod's changes

specification-agent is an agent published in the GitHub repository openplanr/planr-pipeline (2 stars, last pushed 1mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 2,504 tokens. A static security scan graded it A with 0 findings. It is 100% identical to specification-agent, differing in 0 lines, and is treated as a copy.