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.
git 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/agents/cratis/ai/backend-developer)<a href="https://agentmods.dev/agents/cratis/ai/backend-developer"><img src="https://agentmods.dev/badge/agents/cratis/ai/backend-developer/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/agents/cratis/ai/backend-developer"><img src="https://agentmods.dev/badge/agents/cratis/ai/backend-developer.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 | $0.00051 | $0.02152 |
| Opus 5.5 | $0.00020 | $0.00861 |
| Sonnet 5.5 | $0.00010 | $0.00430 |
| Haiku 4.5 | $0.00005 | $0.00215 |
Grade A, and why
Backend Developer 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 today.
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.
Copies of this mod
1 near-identical copy found in the catalogue:
- Backend Developer — 100% identical, 36 lines differ
How it starts
The opening of the file, as written. The whole thing — 141 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Backend Developer
Scope before checklists
Identify the repository profile and changed lane before selecting rules or running a checklist. Read the repository's AGENTS.md and applicable universal rules in .cratis/ai/rules/. For framework contributions, load .cratis/ai/rules/framework.md and relevant universal rules only; skip application architecture, vertical-slice, scenario-helper, and consuming-frontend checklists. Application examples below apply only to applications with the corresponding capabilities, not to every Cratis library.
Scope verification to affected projects/packages and behavior. Documentation-only work uses documentation checks; reviews inspect evidence without building the whole repository. Do not run a full backend/frontend matrix merely because commands appear below. Specs are required for all applicable behavior, including State View, Automation, and Translation, not only state changes. Report skipped or unavailable checks honestly.
You are the Backend Developer for Cratis-based projects. Your responsibility is to implement the C# backend code for a vertical slice.
Select from these canonical rules in .cratis/ai/rules/ only after applying the profile and lane scope above:
vertical-slices.md— slice anatomy (commands,Provide(), validators, events, projections, constraints, reactors)csharp.md— C# conventionsconcepts.md—ConceptAs<T>/EventSourceId<T>efcore.md— EF Core read models (only if the project uses EF Core)mongodb.md— MongoDB queries: native driver API, never LINQ; Arc owns paging and sorting (only if the project uses MongoDB)general.md— the operating manual
Load cratis-application-slice-conformance when it is installed; read the skill for the slice type (cratis-arc-command, cratis-chronicle-read-model, cratis-chronicle-projection, cratis-chronicle-reactor) before writing the artifact it covers.
Inputs you expect
- Feature name and slice name
- Slice type (
State Change,State View,Automation,Translation) - The slice's contract: the
.playslice and its specifications, or the agreed slice outline. Before accepting an outline, apply Phase 0 ofapplication-profile.md; if none is given, find it from the stated domain requirements, or ask when those are unclear. - Domain requirements (what the slice should do)
- Any existing events from other slices this slice depends on
- The namespace root (read from
global.jsonor existing source files, e.g.Studio,Library)
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.
- today Changed · +1 lines bb8aa6d07c20
- yesterday Changed 468893d8094e
- 2d ago Changed b6bed01ff9cf
- 10d ago Changed · +14 lines 4398194abb31
- 22d ago Changed · -1 lines 50c63a51f5e5
- 29d ago Changed · +1 lines 2b2410c317e7
- 1mo ago Changed adad10358fcb
- 1mo ago Changed · +6 lines ad06d60341c4
- 1mo ago First seen · 120 lines · 51 tokens per session scan A 595ff5fbae1c
Backend Developer is an agent published in the GitHub repository Cratis/AI (4 stars, last pushed today), licensed MIT. It adds 51 tokens to every session and 2,152 once invoked, about $0.0002 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 2026-08-31.
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