openspec-ff-change

openspec-ff-change is a skill for Claude Code, Codex from Fission-AI/OpenSpec. It costs 34 tokens per session (1,756 once invoked), scanned A, original, MIT.

A fast workflow for creating all OpenSpec documents needed before implementation. OpenSpec is a system for describing and tracking code changes with specification files.

In plain words
What is it for?
Quickly preparing a change proposal, design, and other required artifacts so implementation can begin.
Why use it?
It avoids stopping after each document when the goal and change name are already clear.

Skill for Claude CodeCodex

About the project

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.

Fission-AI/OpenSpec · 66,949 stars · on GitHub

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

Made for: Claude Code, Codex.

Wrote 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.

agentmods badge for openspec-ff-change

README.md
[![agentmods](https://agentmods.dev/badge/skills/fission-ai/openspec/openspec-ff-change.svg)](https://agentmods.dev/skills/fission-ai/openspec/openspec-ff-change)
Your own site
<a href="https://agentmods.dev/skills/fission-ai/openspec/openspec-ff-change"><img src="https://agentmods.dev/badge/skills/fission-ai/openspec/openspec-ff-change.svg" alt="Measured on agentmods" height="20"></a>
Per session 34 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,756 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 $0.00034 $0.01756
Opus 5 $0.00017 $0.00878
Sonnet 5 $0.00007 $0.00351
Haiku 4.5 $0.00003 $0.00176

Measured 5d ago against content hash 457be3901279, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

openspec-ff-change 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 5d 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-ff-change/SKILL.md · 113 lines

How it starts

The opening of the file, as written. The whole thing — 113 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Fast-forward through artifact creation - generate everything needed to start implementation in one go.

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.

Input: The user's request should include a change name (kebab-case) OR a description of what they want to build.

Steps

  1. If no clear input provided, ask what they want to build

    Ask the user (open-ended, no preset options):

    "What change do you want to work on? Describe what you want to build or fix."

    From their description, derive a kebab-case name (e.g., "add user authentication" → add-user-auth).

    IMPORTANT: Do NOT proceed without understanding what the user wants to build.

  2. Create the change directory

    openspec new change "<name>"
    

    This creates a scaffolded change in the planning home resolved by the CLI.

  3. Get the artifact build order

    openspec status --change "<name>" --json
    

    Parse the JSON to get:

    • applyRequires: array of artifact IDs needed before implementation (e.g., ["tasks"])
    • artifacts: list of all artifacts, each with its status and its requires edges (the artifact IDs it directly depends on)
    • planningHome, changeRoot, artifactPaths, and actionContext: path and scope context. Use these instead of assuming repo-local paths.
  4. Create every artifact in the required set

    Use a todo list to track progress through the artifacts.

    Loop through artifacts in dependency order (artifacts with no pending dependencies first):

    a. For each artifact that is ready (dependencies satisfied):

    • Get instructions:
      openspec instructions <artifact-id> --change "<name>" --json
      
    • The instructions JSON includes:
      • context: Project background (constraints for you - do NOT include in output)
      • rules: Artifact-specific rules (constraints for you - do NOT include in output)
      • template: The structure to use for your output file
      • instruction: Schema-specific guidance for this artifact type
      • skipped/warning: present when the change declares skip_specs and this artifact must NOT be created - stop and pick another artifact
      • resolvedOutputPath: Resolved path or pattern to write the artifact
      • dependencies: Completed artifacts to read for context
    • Read any completed dependency files for context - always re-read them from disk, even if you saw them earlier in the conversation (the user may have edited them)
    • If the instruction field delegates creation to a specific skill or command, invoke it to produce the artifact instead of writing the file yourself, then verify the artifact file exists at resolvedOutputPath
    • Otherwise create the artifact file using template as the structure and write it to resolvedOutputPath. If resolvedOutputPath is a glob, follow instruction to choose the concrete file path
    • Apply context and rules as constraints - but do NOT copy them into the file
    • Show brief progress: "✓ Created "

    b. Continue until every artifact in the required set exists (not just apply.requires)

    • After creating each artifact, re-run openspec status --change "<name>" --json
    • The required set is applyRequires plus every artifact reachable from those by following the requires edges in status --json - walk them transitively (spec-driven closes over proposal, specs, design, tasks). Leave artifacts outside that set alone
    • status is file-existence only, so an applyRequires artifact reading done does NOT mean its dependencies exist - writing tasks.md early marks tasks done while specs was never written. Use each artifact's requires edges, not its status, to build the required set: a done artifact still lists what it depends on
    • An artifact already reading status: "skipped" is satisfied: the change declares skip_specs in .openspec.yaml, so its files must NOT exist. Never try to create one
    • Create every artifact in the required set that is missing, then re-check - creating one can unblock others
    • Skip one only when status already reports it skipped, or when its own instruction says it is conditional: run openspec instructions <artifact-id> --change "<name>" --json and skip only if its instruction field marks it optional (e.g. "create only if..."). Spec-driven's design.md qualifies; specs qualifies only via the skipped status above, never by your own judgment. Tell the user, and do not reconsider it
    • Dependencies are enablers, not gates: if a required artifact is still blocked only because you skipped a conditional dependency, write it anyway
    • Stop when every artifact in the required set is done, skipped, or was deliberately skipped

Read the full file on GitHub · 113 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. 5d ago First seen · 113 lines · 34 tokens per session scan A 457be3901279

Subscribe to this mod's changes

openspec-ff-change is a skill published in the GitHub repository Fission-AI/OpenSpec (66,949 stars, last pushed 3d ago), licensed MIT. It adds 34 tokens to every session and 1,756 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.