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.
npx skills add Cratis/AI --skill cratis-event-model-diagramgit clone --depth 1 https://github.com/Cratis/AIWrote 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.
[](https://agentmods.dev/skills/cratis/ai/cratis-event-model-diagram)<a href="https://agentmods.dev/skills/cratis/ai/cratis-event-model-diagram"><img src="https://agentmods.dev/badge/skills/cratis/ai/cratis-event-model-diagram.svg" alt="Measured on agentmods" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00088 | $0.01605 |
| Opus 5 | $0.00044 | $0.00803 |
| Sonnet 5 | $0.00018 | $0.00321 |
| Haiku 4.5 | $0.00009 | $0.00161 |
Grade A, and why
cratis-event-model-diagram 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 yesterday.
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.
How it starts
The opening of the file, as written. The whole thing — 143 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Event model diagrams
Render an already-decided event model as a Mermaid eventmodeling diagram that
lives beside the code and is updated in the same change. If the event vocabulary
or the stream boundaries are not yet decided, model first; this skill draws a
chosen model, it does not choose one.
Source authority
Diagrams use Mermaid's native eventmodeling diagram type (Mermaid v11.15
and later). The grammar is owned by Mermaid, and
https://mermaid.js.org/syntax/eventmodeling.html is the authority whenever this
file and Mermaid disagree. Confirm the Mermaid version available to the renderer
before relying on a construct.
The Cratis artifacts a diagram refers to are verified against Cratis.Chronicle
16.45.2 and the Arc query and command surface it is used with.
What an event model is
It arranges a module's commands, events, read models, and automations on a left-to-right business-flow timeline, answering "what happens in this module, and in what order?".
One file per module or feature, alongside the code, with the diagram in a fenced
mermaid block. A system-overview file at the source root shows only
cross-module flows.
Grammar cheat sheet
Frame prefix: tf (timeframe — auto-connects to the previous frame) and
rf (resetframe — breaks the chain; start each independent flow with it). rf
replaces tf; tf N rf Name is invalid.
Frame: <prefix> <number> <type> <EntityName>. The number is unique;
declaration order does not matter because frames position by reference.
| Type | Swimlane | Represents |
|---|---|---|
ui |
UI / Automation | the persona interacting — a persona name, never a screen name |
pcr |
UI / Automation | a reactor or automation processor |
cmd |
Command / Read Model | a command |
rmo |
Command / Read Model | a read model |
evt |
Events | an event type, using the exact self-describing type name |
Multiple sources (->>). A read model or fan-in reactor fed by several
frames references them by frame number:
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- yesterday First seen · 143 lines · 88 tokens per session scan A 5a7df1114bd6
cratis-event-model-diagram is a skill published in the GitHub repository Cratis/AI (2 stars, last pushed yesterday), licensed MIT. It adds 88 tokens to every session and 1,605 once invoked, about $0.0004 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 2026-09-06.
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