SDD Explore

Thinking partner for spec-driven development. No fixed steps, no mandatory output. Available before or during any SDD path.

SPECS_ROOT is resolved by the sdd router before this skill runs. Replace .specs/ with your project's actual specs root in all paths below.

Invocation Notice

• Inform the user when this skill is being invoked by name: sdd-explore.

When to Use

• Before starting any SDD workflow — explore before speccing
• When requirements are unclear and writing a spec would be premature
• During change work when a decision blocks progress
• When you want to investigate the codebase before deciding what to spec

When Not to Use

• You already know what to build — jump to sdd-propose or sdd-derive
• You have existing specs to convert — use sdd-translate

Hard Rule: No Code

Never write or implement code in this skill.

Reading files and searching the codebase is fine — that's investigation. Writing SDD artifacts (proposals, designs, specs) is fine — that's capturing thinking. Writing implementation code is not allowed.

Approach

Start with the user's question

Ask: what are you trying to figure out?

Common entry points:

• "I want to understand how X works before speccing it"
• "I'm not sure if this should be one change or two"
• "I need to figure out the right capability breakdown"

Read existing context

Before forming opinions:

1. Check SPECS_ROOT/specs/ for existing baseline specs
2. Check SPECS_ROOT/changes/ for active changes
3. Read relevant code files if the user wants codebase investigation

One-time suggestion (codebase investigation only): If the user wants to investigate the codebase, check SPECS_ROOT/.sdd/suggested-tools.

• If code-review-graph is not listed: present the suggestion below, then append code-review-graph to that file (create the file and directory if needed).

Do this once and only once.

• If already listed: skip the suggestion.

Suggestion (first run only): code-review-graph is a CLI tool that builds a structural AST graph of your codebase — dependency chains, blast radius, test coverage gaps. Useful for surfacing non-obvious architecture before speccing. Install: uv tool install code-review-graph. Say "skip" to dismiss. This won't appear again.

Thinking tools

Use freely:

• ASCII diagrams for architecture and flows
• Decision tables for tradeoffs
• Lists of forces for or against an approach
• Stakeholder maps, actor lists
• Numbered alternatives with tradeoffs
• Graph-aided investigation (if code-review-graph is installed) — blast-radius queries, dependency chains, test coverage gaps.

Run code-review-graph build then query by capability entry point.

Crystallization

When thinking becomes clear enough to act:

• Offer to create an artifact: "Want me to capture this as a proposal?"

or "Should I sketch a design?"

• Route to the right skill: sdd-propose, sdd-derive, sdd-translate
• Don't force it — the user decides when thinking is done

Output

No required output. May produce:

• Notes, summaries, or decision records (in the conversation)
• SDD artifacts if the user decides to capture decisions (proposal.md, design.md)
• A recommendation for which SDD skill to run next

What You Don't Have To Do

• Follow a script
• Ask the same questions every time
• Produce a specific artifact
• Reach a conclusion
• Stay on topic if a tangent is valuable
• Be brief — this is thinking time

Common Mistakes

• Writing implementation code (forbidden)
• Treating explore as a required step — it's optional, not a gate
• Forcing an artifact when the user just wants to think
• Not reading existing specs before forming opinions about the domain