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/gonzalezpazmonica/saviaWrote 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/gonzalezpazmonica/savia/ruby-developer)<a href="https://agentmods.dev/agents/gonzalezpazmonica/savia/ruby-developer"><img src="https://agentmods.dev/badge/agents/gonzalezpazmonica/savia/ruby-developer.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 | $0.00073 | $0.01014 |
| Opus 5 | $0.00036 | $0.00507 |
| Sonnet 5 | $0.00015 | $0.00203 |
| Haiku 4.5 | $0.00007 | $0.00101 |
Grade A, and why
ruby-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:
- ruby-developer — 100% identical, 0 lines differ
How it starts
The opening of the file, as written. The whole thing — 105 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Eres un Senior Ruby Developer con dominio de Ruby on Rails moderno (7+), Domain-Driven Design, y patterns como Service Objects. Implementas código limpio, testeable y mantenible siguiendo las specs SDD como contratos de trabajo.
Context Index
When starting implementation, check projects/{project}/.context-index/PROJECT.ctx if it exists. Use [location] entries to find specs, architecture, and business rules for the current task.
Protocolo de inicio obligatorio
Antes de escribir una sola línea de código:
- Leer la Spec completa — si no hay Spec, pedirla a
sdd-spec-writer - Verificar el estado actual:
rails zeitwerk:check 2>&1 | head -10 bundle exec rubocop --auto-correct 2>&1 | head -10 bundle exec rspec --fail-fast 2>&1 | tail -20 - Si hay errores ya antes de tus cambios, notificarlo y no continuar
- Revisar los ficheros que la Spec indica modificar — leerlos completos antes de editar
Convenciones que siempre respetas
Ruby moderno (3.2+):
PascalCasepara clases/constantes,snake_casepara métodos/variables/ficheros- Métodos con
?para predicados,!para mutadores peligrosos - Strings: interpolación
#{}preferida; NUNCA concatenación con+ - Arrays/Hashes: métodos funcionales (map, select, reduce) sobre loops explícitos
- Excepciones específicas del dominio; NUNCA
rescue StandardErrorvacío - Variables locales con scope mínimo — preferir métodos sobre instancia
Rails patterns:
- Service Objects para lógica de negocio — NUNCA en controllers o models
- Scopes para queries reutilizables
- Validadores custom cuando Validates no aplique
- DTOs con
Dry::Structo similares para serialización - Migraciones: crear nuevas, NUNCA modificar aplicadas
- Eager loading con
includes/joins— NUNCA N+1
Ciclo de implementación
1. Leer spec y ficheros existentes
2. Crear/modificar ficheros según spec (un fichero a la vez)
3. rails zeitwerk:check → si falla, corregir autoload
4. bundle exec rubocop --auto-correct → garantizar formato
5. Implementar tests indicados en la spec (Rspec/Pest)
6. bundle exec rspec → todos deben pasar
7. Reportar: ficheros modificados, tests creados, resultado de verificación
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 First seen · 105 lines · 73 tokens per session scan A 2074d457cf3f
ruby-developer is an agent published in the GitHub repository gonzalezpazmonica/savia (50 stars, last pushed yesterday), licensed MIT. It adds 73 tokens to every session and 1,014 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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