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-arc-hostinggit 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-arc-hosting)<a href="https://agentmods.dev/skills/cratis/ai/cratis-arc-hosting"><img src="https://agentmods.dev/badge/skills/cratis/ai/cratis-arc-hosting/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.
<a href="https://agentmods.dev/skills/cratis/ai/cratis-arc-hosting"><img src="https://agentmods.dev/badge/skills/cratis/ai/cratis-arc-hosting.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00096 | $0.01186 |
| Opus 5.5 | $0.00038 | $0.00474 |
| Sonnet 5.5 | $0.00019 | $0.00237 |
| Haiku 4.5 | $0.00010 | $0.00119 |
Grade A, and why
cratis-arc-hosting 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.
How it starts
The opening of the file, as written. The whole thing — 101 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Host Arc for .NET
Choose the host and integrations before copying a bootstrap. Arc is standalone
CQRS; Chronicle is optional and its client connects to a separate event store.
Nothing in AddCratis() runs the Chronicle engine in your application.
Read references/connection-resolution.md when MongoDB or EF Core connections must resolve per tenant or use separate runtime and schema identities.
Verified product sources
| Package | Purpose |
|---|---|
Cratis, Cratis.Arc, Cratis.Arc.Core |
Composition, ASP.NET hosting and standalone host |
Cratis.Arc.Chronicle, Cratis.Arc.MongoDB, Cratis.Arc.EntityFrameworkCore |
Optional client/storage integrations |
Cratis.Arc.Screenplay.Embedded |
Optional embedded event-model explorer |
Source: Arc. Check signatures against the consumer's installed version.
Choose one bootstrap
| Setup | Configure before Build | Activate after Build |
|---|---|---|
ASP.NET, full event-sourced stack (Cratis) |
builder.AddCratis(...) |
app.UseCratis() |
ASP.NET, Arc only (Cratis.Arc) |
builder.AddCratisArc(...) |
app.UseCratisArc() |
Standalone HTTP host (Cratis.Arc.Core) |
ArcApplication.CreateBuilder(args), then builder.AddCratisArc(...) |
app.UseCratisArc() |
Full-stack ASP.NET bootstrap (requires the Cratis package and configured
Chronicle connection; it deliberately does not opt into unsigned headers):
// Copyright (c) Cratis. All rights reserved.
// Licensed under the MIT license. See LICENSE file in the project root for full license information.
using Microsoft.AspNetCore.Builder;
var builder = WebApplication.CreateBuilder(args);
builder.AddCratis();
var app = builder.Build();
app.UseCratis();
app.Run();
AddCratis composes Arc, WithChronicle and the Microsoft Identity Platform
header scheme. For your own authentication use AddCratisArc plus
WithChronicle, not AddCratis. For Arc without event sourcing use
AddCratisArc and your storage/services. On the standalone host the listen URL
comes from ArcOptions.Hosting.ApplicationUrl, not an argument to UseCratisArc.
Read integrations and publish boundaries
when selecting storage, disabling MVC, adding generated JSON contracts, or
configuring the explorer.
What ships with it
2 files 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.
- 3d ago Changed · +3 lines 5952cff1d993
- 6d ago Changed · +1 lines e171d4fdbab3
- 7d ago Changed 64b50971e3a2
- 9d ago First seen · 97 lines · 96 tokens per session scan A 94e5428784f9
cratis-arc-hosting is a skill published in the GitHub repository Cratis/AI (4 stars, last pushed yesterday), licensed MIT. It adds 96 tokens to every session and 1,186 once invoked, about $0.0004 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 2026-10-13.
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