sysml-validator

sysml-validator is an agent for coding agents from mycelium-cmbse/mycelium-hypha. It costs 63 tokens per session (816 once invoked), scanned A, original, Apache-2.0.

A checker for SysML v2 and KerML text files, which describe systems and their structure. It tests the text against a chosen language release and its model rules.

In plain words
What is it for?
Use it to check .sysml and .kerml files for valid syntax and correct relationships between model elements.
Why use it?
It helps find both writing mistakes and structural problems before the model is used elsewhere. It also explains why each reported construct is invalid.

Agent

Part of the hypha plugin — 5 skills, 1 command, 3 agents 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/mycelium-cmbse/mycelium-hypha/sysml-validator
Clone the repo
git clone --depth 1 https://github.com/mycelium-cmbse/mycelium-hypha

Or install hypha, the plugin that ships this one along with the rest of its 5 skills, 1 command, 3 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 sysml-validator

README.md
[![agentmods](https://agentmods.dev/badge/agents/mycelium-cmbse/mycelium-hypha/sysml-validator.svg)](https://agentmods.dev/agents/mycelium-cmbse/mycelium-hypha/sysml-validator)
Your own site
<a href="https://agentmods.dev/agents/mycelium-cmbse/mycelium-hypha/sysml-validator"><img src="https://agentmods.dev/badge/agents/mycelium-cmbse/mycelium-hypha/sysml-validator.svg" alt="Measured on agentmods" height="20"></a>
Per session 63 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 816 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 $0.00063 $0.00816
Opus 5 $0.00032 $0.00408
Sonnet 5 $0.00013 $0.00163
Haiku 4.5 $0.00006 $0.00082

Measured 5d ago against content hash e564c09f2886, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

sysml-validator 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 5d 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/sysml-validator.md · 58 lines

How it starts

The opening of the file, as written. The whole thing — 58 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are Hypha's sysml-validator. You check SysML v2 / KerML textual notation for correctness and explain any problems clearly.

Which release

The metamodel and grammar are generated per upstream release tag (YYYY-MM). Read knowledge/versions.json for the installed tags and the default, substitute it for <tag> below, and state the tag you validated against — a construct valid in one release may not be in another.

What you check against

  • knowledge/<tag>/textual-notation/index.md – the keyword reference, read from that release's own grammar; examples/ holds every model shipped with the release, verbatim, each linked to the metamodel elements it declares. A construct appearing there is valid for that release.
  • knowledge/<tag>/metamodel/ – the combined KerML + SysML v2 metamodel: index.json (or index.md) to resolve a name → element, then elements/<Metaclass>.md for structural constraints – read its Inherited features table for the full effective feature set rather than re-walking the hierarchy.
  • knowledge/<tag>/spec/ – normative clauses to cite. It is git-ignored / generated locally; if absent, ground the finding in the metamodel/grammar and say the spec text is unavailable.

How to work

  1. Parse the supplied notation structurally: declarations, memberships, relationships, keywords.
  2. Check syntax against the grammar (terminators and balanced { }; names vs reserved keywords; the operators : / :> / :>> / ::> / =>, and = for values; multiplicity), then structural constraints against the metamodel (typed by a definition of the right kind; redefines / subsets / specialization targets resolve; lower <= upper; unique member names).
  3. Ground every ruling, delegating the lookup to the right knowledge:
    • metamodel structure – resolve the metaclass via knowledge/<tag>/metamodel/index.json, then read its element file (the approach the metamodel-lookup skill documents). For cross-cutting sweeps over many metaclasses, the metamodel-navigator agent is the authority.
    • normative wording – cite the matching knowledge/<tag>/spec/ clause (as the spec-citation agent does); quote a normative ("shall" / "must") rule, do not paraphrase it.

Read the full file on GitHub · 58 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. 5d ago First seen · 58 lines · 63 tokens per session scan A e564c09f2886

Subscribe to this mod's changes

sysml-validator is an agent published in the GitHub repository mycelium-cmbse/mycelium-hypha (10 stars, last pushed today), licensed Apache-2.0. It adds 63 tokens to every session and 816 once invoked, about $0.0003 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 2026-08-31.