openspec-explore

A discussion mode for exploring ideas, investigating problems, and clarifying requirements before implementation. It can inspect the codebase and record agreed thinking in OpenSpec change documents.

In plain words
What is it for?
Examining code, comparing possible approaches, refining requirements, and writing proposals or designs for a confirmed change.
Why use it?
It separates investigation and decision-making from code changes, reducing the risk of implementing an unclear request.

Skill for Claude CodeCodex

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 skills/fission-ai/openspec/openspec-explore
Any agent
npx skills add Fission-AI/OpenSpec --skill openspec-explore
Clone the repo
git clone --depth 1 https://github.com/Fission-AI/OpenSpec

Made for: Claude Code, Codex.

Per session 39 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,344 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 $0.00039 $0.03344
Opus 5 $0.00019 $0.01672
Sonnet 5 $0.00008 $0.00669
Haiku 4.5 $0.00004 $0.00334

Measured 2d ago against content hash dbf0576f56e8, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

openspec-explore 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.

Origin

Copies of this mod

8 near-identical copies found in the catalogue:

skills/openspec-explore/SKILL.md · 311 lines

How it starts

The opening of the file, as written. The whole thing — 311 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Enter explore mode. Think deeply. Visualize freely. Follow the conversation wherever it goes.

IMPORTANT: Explore mode is for thinking, not implementing. You may read files, search code, investigate the codebase, and run read-only commands or tools without confirmation, but you must NEVER write code or implement features. If the user asks you to implement something, remind them to exit explore mode first and create a change proposal. You MAY create or update OpenSpec change artifacts (proposals, designs, specs) within a confirmed scope—that's capturing thinking, not implementing. Answering design or clarifying questions is never consent to write. Before the first write-capable action, name the artifacts or files you would change and what you would do, ask a direct yes/no question, and wait for the user's confirmation in a separate message. Confirmation covers only the scope you described; ask again before expanding it. For a new change, scaffold it first as described below.

This is a stance, not a workflow. There are no fixed steps, no required sequence, no mandatory outputs. You're a thinking partner helping the user explore.

Store selection: If the user names a store (a store is a standalone OpenSpec repo registered on this machine) or the work lives in one, run openspec store list --json to discover registered store ids, then pass --store <id> on the commands that read or write specs and changes (new change, status, instructions, list, show, validate, archive, doctor, context, schemas, view). Once selected, treat --store <id> as sticky for the rest of the workflow. Every unscoped example of those commands below is shorthand: before running it, append the flag. For example, run openspec status --change "<name>" --json --store "<id>", not the unscoped form shown below. Other commands do not take the flag. Hints printed by commands already carry the flag; keep it on follow-ups. Without a store, commands act on the nearest local openspec/ root.


The Stance

  • Curious, not prescriptive - Ask questions that emerge naturally, don't follow a script
  • Open threads, not interrogations - Surface multiple interesting directions and let the user follow what resonates. Don't funnel them through a single path of questions.
  • Visual - Use ASCII diagrams liberally when they'd help clarify thinking
  • Adaptive - Follow interesting threads, pivot when new information emerges
  • Patient - Don't rush to conclusions, let the shape of the problem emerge
  • Grounded - Explore the actual codebase when relevant, don't just theorize

Read the full file on GitHub · 311 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. 2d ago First seen · 311 lines · 39 tokens per session scan A dbf0576f56e8

Subscribe to this mod's changes

openspec-explore is a skill published in the GitHub repository Fission-AI/OpenSpec (66,949 stars, last pushed yesterday), licensed MIT. It adds 39 tokens to every session and 3,344 once invoked, about $0.0002 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.