nova-backend-plan

Inputs

Parameter	Required	Default	Notes
PLAN_OUTPUT_PATH	Yes	None	Safety-boundary output file for the Java/Spring plan.
PLAN_INTENT	Yes	Infer from payload	Business or technical goal for the backend plan.
PLAN_PROFILE	No	java-backend	Fixed Java/Spring backend profile.
ANALYSIS_INPUTS	Recommended	None	Prior exploration or analysis artifacts.
CONSTRAINTS	No	None	Architecture, compatibility, delivery, or operational limits.

Parameter Resolution

• Parse natural-language payload, explicit KEY=value, --flag value, and --flag=value forms from $ARGUMENTS.
• Normalize parameter names to uppercase snake case and map known mode words before assigning remaining text to PLAN_INTENT.
• Explicit values win over inferred values only when they do not conflict with another explicit value.
• Apply documented defaults only when unambiguous; probe Git status, base branches, and latest artifacts only for context parameters.
• Safety-boundary parameters for this skill: PLAN_OUTPUT_PATH.
• In non-interactive mode, fail before side effects when required or safety-boundary parameters are missing.
• Full policy: nova-plugin/skills/_shared/parameter-resolution.md.

Safety Preflight

• This skill declares side-effect-capable tools: Write, Edit.
• Resolve parameters and present a preflight card before writing artifacts, editing project files, or running Bash.
• Show files or artifacts that may be written, scripts or commands that may run, disallowed operations, and the proceed condition.
• Do not infer missing safety-boundary values; ask once in interactive mode or fail in non-interactive mode.
• Preserve repository constraints: no destructive Git cleanup, no branch deletion, no push/merge/rebase, no editing archived agents as active agents.
• Full policy: nova-plugin/skills/_shared/safety-preflight.md.

Outputs

• Follow the skill-specific output rules below and the shared output contract.
• For written artifacts, report the path and a short executive summary instead of pasting the full artifact into chat.
• For reviews and verification, lead with findings or verdicts and state residual risk.
• Full policy: nova-plugin/skills/_shared/output-contracts.md.
• Artifact policy: nova-plugin/skills/_shared/artifact-policy.md.

Workflow

1. Resolve parameters using the shared policy and this skill's input table.
2. Read only the context needed for the requested scope.
3. Apply the skill-specific guidance and migrated slash command contract below.
4. Respect safety preflight before any side effects.
5. Produce the required output and report validation or skipped validation honestly.

Failure Modes

• Required payload is missing or ambiguous.
• A safety-boundary parameter is missing, conflicting, or unsafe to infer.
• Required files, scripts, CLIs, credentials, or runtime dependencies are unavailable.
• Existing user changes overlap the intended write scope and cannot be merged safely.
• Repository policy conflicts with the requested action.

Examples

• Use /backend-plan as a Java/Spring profile shortcut for /produce-plan.
• Explicit parameters may use KEY=value or --flag value; natural-language payload is accepted when unambiguous.

Skill-Specific Guidance

Purpose

Produce a complete Java/Spring backend design artifact for senior review.

Inputs

Parameter	Required	Default	Notes	Example
PLAN_OUTPUT_PATH	Yes	N/A	Required output path	docs/plans/payment-callback.md
Business context	Recommended	N/A	Problem, goals, constraints	Duplicate callback handling

Outputs

• Writes 12-section backend design doc to file.
• Chat output limited to path + 3-5 executive bullets.

Workflow

1. Validate output path.
2. Extract assumptions and constraints.
3. Choose one design option with rejection rationale for alternatives.
4. Write full 12-section document.

Examples

• Natural trigger: Use backend-plan for this Java/Spring order refund flow.
• Explicit trigger: backend-plan PLAN_OUTPUT_PATH=docs/plans/refund-v2.md.

Safety

• No implementation code changes.
• Do not infer missing output path.

Migrated Slash Command Contract

Migrated from the pre-thin slash command contract for /backend-plan (nova-plugin/commands/backend-plan.md).

JAVA / SPRING BACKEND DESIGN PLAN

TASK: PRODUCE A JAVA / SPRING BACKEND DESIGN PLAN

You are Claude Code acting as a senior Java backend engineer / system designer.

Think carefully. Design decisions here will directly guide implementation.

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REQUIRED INPUT EXTRACTION

From $ARGUMENTS, extract:

1. PLAN_OUTPUT_PATH (Required)

PLAN_OUTPUT_PATH: $PLAN_OUTPUT_PATH

If PLAN_OUTPUT_PATH is missing:

• STOP immediately
• Ask the user to explicitly provide it

You MUST NOT guess or invent a path.

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GENERAL RULES (STRICT)

• DO NOT write or modify any Java code
• This step is DESIGN ONLY
• DO NOT assume implementation details not justified by the problem
• DO NOT over-optimize or design speculative features

You MUST:

• Write a COMPLETE design plan to PLAN_OUTPUT_PATH
• Overwrite the file if it already exists
• Create parent directories if missing
• Assume the plan will be reviewed by senior engineers and tech leads

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PLAN DOCUMENT STRUCTURE (MANDATORY)

1️⃣ Background & Problem Statement 2️⃣ Scope Definition 3️⃣ Business Rules & Invariants 4️⃣ Architecture Overview 5️⃣ Data Model & Persistence 6️⃣ Transaction & Consistency Design 7️⃣ Concurrency & Idempotency 8️⃣ Error Handling & Observability 9️⃣ Implementation Plan (Step-by-Step) 🔟 Testing Strategy 1️⃣1️⃣ Rollback & Safety Plan 1️⃣2️⃣ Risks & Open Questions

Each section MUST be explicitly present. Use "N/A" if a section truly does not apply.

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DESIGN QUALITY BAR

The plan MUST be:

• Internally consistent
• Explicit about assumptions
• Clear about trade-offs
• Safe-by-default

If multiple design options exist:

• Choose ONE
• Briefly justify why alternatives were rejected

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OUTPUT RULES

You MUST:

• Write the FULL plan to PLAN_OUTPUT_PATH

In chat output ONLY:

• The file path written
• 3–5 bullet executive summary

You MUST NOT:

• Paste the full plan into chat
• Start implementation
• Suggest future improvements

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END OF COMMAND