reqvire-syseng

reqvire-syseng is a skill for Claude Code from reqvire-org/reqvire. It costs 150 tokens per session (9,311 once invoked), scanned A, original, Apache-2.0.

An engineering-modeling skill for Reqvire, a tool that connects capabilities, requirements, contracts, and verification in a structured project model.

In plain words
What is it for?
Exploring engineering knowledge graphs, defining requirements and capabilities, and creating implementation and verification work.
Why use it?
It helps keep engineering decisions traceable instead of scattering them across disconnected documents.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: mentions CLAUDE.md; mentions Codex.

Part of the reqvire plugin — 4 skills shipped together

Good fit Exploring engineering knowledge graphs, defining requirements and capabilities, and creating implementation and verification work.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/reqvire-org/reqvire/syseng
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 reqvire-org/reqvire --skill syseng
Clone the repo
git clone --depth 1 https://github.com/reqvire-org/reqvire

Made for: Claude Code.

Or install reqvire, the plugin that ships this one along with the rest of its 4 skills.

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 reqvire-syseng

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

Your own site · 80×15
<a href="https://agentmods.dev/skills/reqvire-org/reqvire/syseng"><img src="https://agentmods.dev/badge/skills/reqvire-org/reqvire/syseng.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 150 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 9,311 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 $0.00150 $0.09311
Opus 5.5 $0.00060 $0.03724
Sonnet 5.5 $0.00030 $0.01862
Haiku 4.5 $0.00015 $0.00931

Measured 11d ago against content hash 93c218ea8eee, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

reqvire-syseng 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 11d 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

Copies of this mod

1 near-identical copy found in the catalogue:

claude-plugins/skills/syseng/SKILL.md · 508 lines

How it starts

The opening of the file, as written. The whole thing — 508 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Semantic Engineering and MBSE Skill

You are an expert semantic engineering and MBSE practitioner specializing in Reqvire. You orchestrate Reqvire commands and provide guidance for ontology-driven engineering, capability modeling, requirements, contracts, verification, and AI-native engineering knowledge graphs.

Environment Setup

Use the Reqvire npm runner by default so Codex workflows do not require a separate binary install.

Default command form:

npx -y "${REQVIRE_NPX_PACKAGE:-@reqvire-org/reqvire@latest}" --workspace "$PWD" <command>

Workspace policy:

  • Run commands from the intended effective workspace root, or pass that root with --workspace.
  • The effective workspace root must contain at least one eligible Git worktree; otherwise there is no local SOI model-processing scope.
  • Reqvire parses and reports only files and artifacts under the effective workspace root that are inside eligible Git worktrees. Non-Git workspace folders are ignored.
  • Git worktree roots, branches, remotes, and commits are source-control metadata. They do not redefine Reqvire identifier roots; identifiers and paths stay workspace-root-relative.

To check:

npx -y "${REQVIRE_NPX_PACKAGE:-@reqvire-org/reqvire@latest}" --workspace "$PWD" --version

Version policy:

  • Use @reqvire-org/reqvire@latest by default for assistant workflows.
  • Pin by setting REQVIRE_NPX_PACKAGE, for example export REQVIRE_NPX_PACKAGE=@reqvire-org/[email protected].
  • Use a locally installed reqvire binary only when the user explicitly needs offline or non-npm execution.

Element Types

Category Type Purpose
Capabilities capability Coherent operational, product, business, regulatory, or system ability that bridges ontology, requirements, and verification
Requirements requirement Implementable system obligations (functional, performance, interface, compliance)
Ontology ontology First-class OWL/Turtle vocabulary and semantic model terms reusable by capabilities and requirements
semantic-contract Reusable SHACL shape profile that uses ontology and constrains requirements
semantic-query Managed SPARQL artifact with explicit ontology context, deterministic export, and downstream execution
Concepts concept-scheme Native SKOS thesaurus or concept-scheme root that owns concept_base and concept_prefix
concept Native curated SKOS concept generated from Markdown body text, labels, examples, and concept relations
Contracts source External need, regulation, policy, or source material owned by a requirement
specification Detailed definitions refining a requirement
constraint Limits and boundaries on system behavior
behavior How the system behaves in specific conditions
state Lifecycle states, state machines, transitions, and state-dependent contracts
input-output Payloads, messages, documents, schemas, fixtures, and data contracts
Verification planning verification-objective Verification objective or grouping node; may derive from verification-family elements but does not verify requirements/capabilities and cannot use satisfiedBy
Verifications test-verification Automated/manual testing (evidence-backed; requires satisfiedBy)
formal-proof-verification Formal proof, model checking, theorem proving, generated fixtures, or proof reports (evidence-backed; requires satisfiedBy)
analysis-verification Review, calculation, simulation
inspection-verification Visual examination, audit
demonstration-verification Showing capability works

Read the full file on GitHub · 508 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. 11d ago Changed · +35 lines 93c218ea8eee
  2. 1mo ago Changed · -1 lines 2a4440f7265b
  3. 1mo ago First seen · 474 lines · 150 tokens per session scan A 2120469a30c1

Subscribe to this mod's changes

reqvire-syseng is a skill published in the GitHub repository reqvire-org/reqvire (27 stars, last pushed yesterday), licensed Apache-2.0. It adds 150 tokens to every session and 9,311 once invoked, about $0.0006 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 2026-09-01.