OpenSpec is a specification-driven development framework that records software requirements and implementation plans as readable Markdown artifacts. It helps developers and AI coding assistants agree on what should be built before code is written, including work spanning multiple repositories. The catalogue add-ons provide workflow skills and instructions for using OpenSpec.
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.
npx skills add Fission-AI/OpenSpec --skill openspec-exploregit clone --depth 1 https://github.com/Fission-AI/OpenSpecWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/fission-ai/openspec/openspec-explore)<a href="https://agentmods.dev/skills/fission-ai/openspec/openspec-explore"><img src="https://agentmods.dev/badge/skills/fission-ai/openspec/openspec-explore/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/fission-ai/openspec/openspec-explore"><img src="https://agentmods.dev/badge/skills/fission-ai/openspec/openspec-explore.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
- NVIDIA SkillSpector warn
SkillSpector: 4 findings, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium Excessive Agency · line 14 Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
- medium Excessive Agency · line 37 Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
- medium Excessive Agency · line 143 Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
- medium Excessive Agency · line 330 Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00067 | $0.04905 |
| Opus 5.5 | $0.00027 | $0.01962 |
| Sonnet 5.5 | $0.00013 | $0.00981 |
| Haiku 4.5 | $0.00007 | $0.00490 |
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.
Copies of this mod
8 near-identical copies found in the catalogue:
- openspec-explore — 92% identical, 183 lines differ
- openspec-explore — 92% identical, 183 lines differ
- openspec-explore — 92% identical, 13 lines differ
- openspec-explore — 92% identical, 183 lines differ
- openspec-explore — 92% identical, 183 lines differ
- openspec-explore — 92% identical, 179 lines differ
- openspec-explore — 92% identical, 183 lines differ
- openspec-explore — 92% identical, 181 lines differ
How it starts
The opening of the file, as written. The whole thing — 356 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, do not start it here: say that explore mode does not implement, and point them at /openspec-propose, which turns the discussion into a change. The work happens from that change, never from explore mode. 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. An explicit request from the user to capture the exploration as a new change is itself that confirmation, covering the change and the change artifacts the request names; 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.
Project check: These steps expect a project that already uses OpenSpec. Before the first step that writes anything (new change, archive, sync specs, or authoring an artifact file), confirm the project has a root: run openspec list --json (with --store <id> when a store is selected, since the store is then the root) and read root. A root object means the project is set up. "root": null means it is not - there is no openspec/ directory here, and a write such as openspec new change would create one as a side effect. The command also exits non-zero, which is that answer rather than a broken CLI, so read the JSON instead of retrying or working around it.
One "root": null is not about setup: when a status error message starts with Declared in or Invalid store declaration in and names this project's openspec/config.yaml (or config.yml), the project does use OpenSpec through a store it declares, which this machine cannot resolve (the store is not registered, or the store: line is malformed). Do not treat it as uninitialized and skip the branches below: stop before writing and show the user that error's message and fix.
Otherwise, with no root, what happens next depends on how this workflow was reached:
- Auto-selected: you chose this workflow yourself, without the user naming OpenSpec, naming this skill, or running its slash command. Stop using OpenSpec and answer the request normally, as you would with no OpenSpec installed. Do not ask them to set anything up and do not mention OpenSpec setup.
- Explicit OpenSpec request: the user named OpenSpec, named this skill, or ran its slash command. Stop before writing and ask how to proceed: set this project up (
openspec init), target a store they already have (--store <id>), or continue without OpenSpec for this request. Wait for their answer.
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.
- 2d ago Changed e9fe2acf923d
- 5d ago Changed · +2 lines c7393e713807
- 26d ago Changed 5bc03c568d03
- 1mo ago Changed · +11 lines · +28 tokens per session df199ec7d1ae
- 1mo ago Changed · +8 lines 7c067bebac70
- 1mo ago Changed · +24 lines 31c8fd622fea
- 1mo ago First seen · 311 lines · 39 tokens per session scan A dbf0576f56e8
openspec-explore is a skill published in the GitHub repository Fission-AI/OpenSpec (72,436 stars, last pushed today), licensed MIT. It adds 67 tokens to every session and 4,905 once invoked, about $0.0003 per session on Opus 5.5. 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.
Other skills, from other repositories
add-community-extension
Add a community extension to the Spec Kit catalog from a GitHub issue submission. USE FOR: processing extension submission issues, validating catalog entries, updating catalog.community.json and docs/community/extensions.md, creating PRs. DO NOT USE FOR: creating new extensions from scratch, or first-party extension…
code-review
Reviews Spec Kit code changes for consistency with applicable design documents, positive and negative test coverage, regression evidence for bug fixes, and consistent repository terminology. Use when reviewing a diff or pull request. Do not use for implementing changes or posting GitHub review actions.
openprd-harness
A workflow guide for OpenPrd, a workspace for turning unclear product ideas into clarified requirements and a handoff for implementation. It helps choose and run each stage, from questions through final handoff.
openprd-shared
A shared set of rules for working with OpenPrd, a workspace for turning product ideas into documented requirements and plans.
openprd-frontend-design
A design guide for OpenPrd interface and frontend work. It helps define the page's purpose, visual direction, assets, layout, and quality checks before implementation.
openprd-benchmark-router
A research-routing guide for OpenPrd and coding-agent workflows. It helps choose suitable sources when comparing products, benchmarks, best practices, prompts, agent systems, or interface resources.