explore-design

A command for improving the technical design of an issue or OpenSpec change before coding begins. It reviews possible approaches, trade-offs, compatibility, rollout, and verification.

In plain words
What is it for?
Use it to refine an issue or specification, compare technical alternatives, plan staged database changes, or define test-first verification.
Why use it?
It helps expose design gaps and settle implementation details before changes are made.

Command for Cursor

Install

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.

agentmods
npx agentmods add commands/jabrena/plinth/explore-design
Clone the repo
git clone --depth 1 https://github.com/jabrena/plinth

Made for: Cursor.

Per session 15 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 936 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5 $0.00015 $0.00936
Opus 5 $0.00008 $0.00468
Sonnet 5 $0.00003 $0.00187
Haiku 4.5 $0.00002 $0.00094

Measured 3d ago against content hash d4bbd399bc76, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

explore-design 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 3d 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.

.cursor/commands/explore-design.md · 81 lines

How it starts

The opening of the file, as written. The whole thing — 81 lines — stays where its author put it; the contents beside it link to each section on GitHub.

explore-design

Improve and refine the technical approach for an issue or OpenSpec change after initial specification—with alternatives, trade-offs, compatibility review, rollout controls, and verification strategy—before implementation.

Usage

/explore-design <issue|openspec-change>

Accepted Inputs

  • Issue or user story
  • OpenSpec change with unresolved technical approaches or design gaps
  • Existing architecture context and constraints
  • Relevant requirements, ADRs, or technical notes linked to the issue or change

Owning Agent

@plinth-architect

Associated Skills

  • 051-design-two-steps-methods for every refinement so preparatory work, behavior change, and verification remain explicitly sequenced
  • 052-design-hamburger-method when the scope is broad enough to need smallest-useful vertical slices
  • 053-design-simple-rules when alternatives need ordered design tradeoff evaluation before finalizing the direction
  • 054-design-tdd when testing-related requirements need test-first sequencing and verification-driven refinement
  • 055-design-parallel-change when database migration requirements need expand, migrate, contract sequencing
  • 056-design-avoid-breaking-changes when compatibility surfaces may change during refinement
  • 057-design-feature-toggles when rollout, rollback, compatibility windows, or temporary behavior controls affect the design direction
  • 059-design-atdd as the final alignment gate when an OpenSpec change provides a proposal, specification scenarios, and a task checklist
  • 121-java-object-oriented-design, then 122-java-type-design, then 123-java-design-patterns when Java responsibilities, type boundaries, or collaboration decisions affect the refined approach
  • 130-java-testing-strategies when testing strategy, boundary coverage, flakiness, or verification quality affect the refined approach

Workflow position

Runs after /create-spec, not as the first mission in the workflow.

Workflow

Read the full file on GitHub · 81 lines

Changes

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.

  1. 3d ago First seen · 81 lines · 15 tokens per session scan A d4bbd399bc76

Subscribe to this mod's changes

explore-design is a command published in the GitHub repository jabrena/plinth (435 stars, last pushed 2d ago), licensed Apache-2.0. It adds 15 tokens to every session and 936 once invoked, about $0.0001 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 2026-08-30.