Scaffold Message Handler

STOP - Read before ANY tool call

1. Read {{GUARDRAILS_PATH}}
2. Read _shared/sdd-artifacts/SESSION.md; load session-state for $Cwd
3. If the relevant gate is not approved: STOP - ask user (pt-BR) - do NOT Write/Shell
4. SDD/develop skills: after ONE step/task, STOP session - handoff only
5. This skill body is English; user-facing prompts may be (pt-BR)

Step -1 - Gate check (report in chat before continuing)

Gate check:
[ ] guardrails.mdc read
[ ] SESSION.md read; session-state loaded
[ ] PIPELINE.md read (SDD skills only)
[ ] User confirmed current action (sim)
-> If any unchecked: STOP

Skill: scaffold-message-handler

Status

Scaffold - guides discovery, requirements, and implementation in the target repository. This toolkit ships no embedded corporate consumer templates or org-specific wiring.

Trigger

Invoke when the user asks for: /scaffold-message-handler, create message consumer, /scaffold-message-handler, or when a PLAN step adds a new queue/topic handler.

Optional arguments: message or event name, queue/topic name, or path to an existing consumer to mirror.

Outcome

In the target workspace (not this toolkit repo unless it is the .NET repo under work):

1. Detected messaging stack and reference consumer(s)
2. Confirmed requirements (payload, errors, idempotency, retry, DLQ)
3. Proposed file layout aligned with the repo
4. Scaffold code and tests only after user confirmation - following existing project patterns, not copied templates from this repo

Lazy-load

Process

0. Workspace

Confirm target .NET repository (.sln or worker/API with messaging). If the workspace is the toolkit only, stop and ask which repo to open.

1. Detect messaging stack

Grep/Glob per reference.md section Stack detection. Report:

Default when none detected: MassTransit with RabbitMQ transport (implicit). Still collect requirements before scaffolding. Use Azure Service Bus only when ASB packages or existing ASB wiring are already in the repo.

Do not require corporate docs/consumidores/ paths.

2. Find conventions

Glob existing consumers/handlers in the repo. Note: namespace layout, registration (AddMassTransit, hosted service, etc.), message contract location, test project pattern.

If no consumer exists, say so and propose a layout consistent with Clean Architecture after reading clean-architecture.md.

3. Collect requirements (blocker before code)

Ask using reference.md section Requirements checklist. Minimum:

• Queue or topic name (and subscription if applicable)
• Message contract (type name, key fields, schema source)
• Processing responsibility (what changes in the system)
• Error handling: retry count/backoff, DLQ or error queue
• Idempotency strategy (natural key, outbox, dedup store)
• Test expectations (unit vs integration)

Wait for answers. Do not invent queue names or payloads.

4. Propose scaffold plan

Present:

• Files to add or extend (paths from repo conventions)
• Registration point (DI / MassTransit config)
• Test files and how to run them

Ask explicit confirmation before writing code.

5. Implement (target repo only)

After confirmation:

1. Load clean-architecture.md and csharp-patterns.md
2. Mirror naming and folder structure from step 2
3. Add consumer/handler, contract if missing, registration, and tests
4. Run dotnet build and targeted dotnet test for affected projects

6. Summarize handoff

Report: stack detected, paths touched, how to run locally, open risks (idempotency, poison messages).

Must not

• Ship or copy hardcoded consumer templates from ai-prompts or internal org repos into the toolkit
• Assume a specific organization or proprietary observability tools
• Generate code before requirements are collected and the user confirms the plan
• Preload entire dotnet-guidelines/ tree beyond clean-architecture and csharp-patterns when coding

Handoff examples

/repair-dotnet-build

/sdd-develop - <full-plan-path> - Step N

SDD PLAN paths: resolve per {{TOOLKIT_ROOT}}/skills/_shared/sdd-artifacts/STORAGE.md (features/**/PLAN/PLAN_*.md or global {{SDD_ROOT}}/<repo-id>/features/**/PLAN/ only). Not root/flat PLAN/ and not docs/documentation-plan/plan.md.