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 agentmods add skills/snk-devcenter/addon-studio/listenernpx skills add snk-devcenter/addon-studio --skill listenergit clone --depth 1 https://github.com/snk-devcenter/addon-studioWhat 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 | $0.00361 | $0.04112 |
| Opus 5 | $0.00180 | $0.02056 |
| Sonnet 5 | $0.00072 | $0.00822 |
| Haiku 4.5 | $0.00036 | $0.00411 |
Grade A, and why
listener 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 2d 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 — 274 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Listener de Persistência (@Listener) — Addon Studio 2.0
@Listener executa lógica personalizada em eventos de persistência (CRUD) de uma entidade JAPE — antes/depois de insert, update e delete. Funciona em entidades do próprio add-on e em instâncias nativas do sistema (CabecalhoNota, Parceiro, Produto, etc.). A anotação registra o listener automaticamente — sem edição manual de XML.
⚠️
@Listener≠@BeforeLoadListener. São mecanismos distintos, com anotação, interface, evento e escopo diferentes:@Listenerreage a escrita (insert/update/delete, viaPersistenceEventAdapter);@BeforeLoadListenerintercepta leitura (busca/carregamento no Finder, viaFinderListener) — e só funciona em instâncias do próprio add-on. Tarefa de leitura/filtro de busca → skillbefore-load-listener.
1. Quando usar — @Listener vs @BeforeLoadListener vs @BusinessRule vs @ActionButton
| Mecanismo | Escopo | Quando usar |
|---|---|---|
@Listener |
CRUD (insert/update/delete) de qualquer entidade | Validar/preencher campos ao gravar/excluir; auditoria; reagir a mudança de dados. |
@BeforeLoadListener |
Toda busca/carregamento de UMA entidade (só do add-on) | Filtro transversal em leitura (segurança, multi-tenant, soft-delete). |
@BusinessRule |
Confirmação/faturamento de notas | Regras transacionais comerciais com barramento de regras. |
@ActionButton |
Ação disparada pelo usuário na tela | Processamento sob demanda, não automático por evento. |
Regra rápida: reagir a gravação/exclusão de registro (automático, sem clique)? @Listener. Filtrar leitura? @BeforeLoadListener. Regra de nota no barramento comercial? @BusinessRule.
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.
- 2d ago First seen · 274 lines · 0 tokens per session scan A 00c22163b0c8
listener is a skill published in the GitHub repository snk-devcenter/addon-studio (5 stars, last pushed 2d ago), licensed MIT. It adds 361 tokens to every session and 4,112 once invoked, about $0.0018 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.
Other skills, from other repositories
systematic-debugging
Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.
brainstorming
You MUST use this before any creative work - creating features, building components, adding functionality, or modifying behavior. Explores user intent, requirements and design before implementation.
chat-pet-sprite-creation
Use when creating or changing VS Code chat pet sprite art, sprite sheets, state animations, eye treatments, Stable/Insiders variants, or pet transitions under src/vs/workbench/contrib/chat/browser/widget/media/chatPet.
cpu-profile-analysis
Analyze V8/Chrome CPU profiles (.cpuprofile) and DevTools trace files (Trace-.json). Use when: profiling performance, investigating slow functions, comparing code paths, finding bottlenecks, analyzing timeToRequest, understanding call trees from sampling profiler data, analyzing layout/paint/rendering, investigating…
babysit-pr
Babysit a GitHub pull request after creation by continuously polling review comments, CI checks/workflow runs, and mergeability state until the PR is merged/closed or user help is required. Diagnose failures, retry likely flaky failures up to 3 times, auto-fix/push branch-related issues when appropriate, and keep…
imagegen
Generate or edit raster images when the task benefits from AI-created bitmap visuals such as photos, illustrations, textures, sprites, mockups, or transparent-background cutouts. Use when Codex should create a brand-new image, transform an existing image, or derive visual variants from references, and the output…