agents-at-scale-ark: Skill for Claude Code

.claude/skills/openspec-sync-specs/SKILL.md

openspec-sync-specs is a skill for Claude Code from mckinsey/agents-at-scale-ark. It costs 38 tokens per session (1,025 once invoked), scanned A, a copy of openspec-sync-specs, Apache-2.0.

A command for applying changes from an OpenSpec draft specification to the project's main specifications without closing the change.

In plain words
What is it for?
Use it when a planned change has updated requirements that should be merged into the project's main specifications.
Why use it?
It keeps the main specifications up to date while allowing the related implementation work to continue.

Skill for Claude Code

Written for Claude Code: installed under .claude/. Also seen: names the AskUserQuestion tool.

This is mckinsey/agents-at-scale-ark's own configuration. It tells Claude Code how to work on agents-at-scale-ark itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything agents-at-scale-ark configures →

Reuse

Borrowing it

Nothing to install: this file belongs to mckinsey/agents-at-scale-ark. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/mckinsey/agents-at-scale-ark/main/.claude/skills/openspec-sync-specs/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/mckinsey/agents-at-scale-ark

Made for: Claude Code.

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-sync-specs

README.md
[![agentmods](https://agentmods.dev/badge/skills/mckinsey/agents-at-scale-ark/openspec-sync-specs/github.svg)](https://agentmods.dev/skills/mckinsey/agents-at-scale-ark/openspec-sync-specs)
Your own site
<a href="https://agentmods.dev/skills/mckinsey/agents-at-scale-ark/openspec-sync-specs"><img src="https://agentmods.dev/badge/skills/mckinsey/agents-at-scale-ark/openspec-sync-specs/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.

agentmods 80×15 button for openspec-sync-specs

Your own site · 80×15
<a href="https://agentmods.dev/skills/mckinsey/agents-at-scale-ark/openspec-sync-specs"><img src="https://agentmods.dev/badge/skills/mckinsey/agents-at-scale-ark/openspec-sync-specs.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 38 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,025 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin 86% copy Near-identical to another mod 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 5.1 $0.00038 $0.01025
Opus 5 $0.00019 $0.00513
Sonnet 5 $0.00008 $0.00205
Haiku 4.5 $0.00004 $0.00103

Measured 7d ago against content hash ea77918baec6, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

openspec-sync-specs 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 7d 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

This is a copy

86% identical to openspec-sync-specs — 21 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.claude/skills/openspec-sync-specs/SKILL.md · 139 lines

How it starts

The opening of the file, as written. The whole thing — 139 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Sync delta specs from a change to main specs.

This is an agent-driven operation - you will read delta specs and directly edit main specs to apply the changes. This allows intelligent merging (e.g., adding a scenario without copying the entire requirement).

Input: Optionally specify a change name. If omitted, check if it can be inferred from conversation context. If vague or ambiguous you MUST prompt for available changes.

Steps

  1. If no change name provided, prompt for selection

    Run openspec list --json to get available changes. Use the AskUserQuestion tool to let the user select.

    Show changes that have delta specs (under specs/ directory).

    IMPORTANT: Do NOT guess or auto-select a change. Always let the user choose.

  2. Find delta specs

    Look for delta spec files in openspec/changes/<name>/specs/*/spec.md.

    Each delta spec file contains sections like:

    • ## ADDED Requirements - New requirements to add
    • ## MODIFIED Requirements - Changes to existing requirements
    • ## REMOVED Requirements - Requirements to remove
    • ## RENAMED Requirements - Requirements to rename (FROM:/TO: format)

    If no delta specs found, inform user and stop.

  3. For each delta spec, apply changes to main specs

    For each capability with a delta spec at openspec/changes/<name>/specs/<capability>/spec.md:

    a. Read the delta spec to understand the intended changes

    b. Read the main spec at openspec/specs/<capability>/spec.md (may not exist yet)

    c. Apply changes intelligently:

    ADDED Requirements:

    • If requirement doesn't exist in main spec → add it
    • If requirement already exists → update it to match (treat as implicit MODIFIED)

    MODIFIED Requirements:

    • Find the requirement in main spec
    • Apply the changes - this can be:
      • Adding new scenarios (don't need to copy existing ones)
      • Modifying existing scenarios
      • Changing the requirement description
    • Preserve scenarios/content not mentioned in the delta

    REMOVED Requirements:

    • Remove the entire requirement block from main spec

    RENAMED Requirements:

    • Find the FROM requirement, rename to TO

    d. Create new main spec if capability doesn't exist yet:

    • Create openspec/specs/<capability>/spec.md
    • Add Purpose section (can be brief, mark as TBD)
    • Add Requirements section with the ADDED requirements
  4. Show summary

    After applying all changes, summarize:

    • Which capabilities were updated
    • What changes were made (requirements added/modified/removed/renamed)

Delta Spec Format Reference

## ADDED Requirements

### Requirement: New Feature
The system SHALL do something new.

#### Scenario: Basic case
- **WHEN** user does X
- **THEN** system does Y

## MODIFIED Requirements

### Requirement: Existing Feature
#### Scenario: New scenario to add
- **WHEN** user does A
- **THEN** system does B

## REMOVED Requirements

### Requirement: Deprecated Feature

## RENAMED Requirements

- FROM: `### Requirement: Old Name`
- TO: `### Requirement: New Name`

Key Principle: Intelligent Merging

Unlike programmatic merging, you can apply partial updates:

  • To add a scenario, just include that scenario under MODIFIED - don't copy existing scenarios
  • The delta represents intent, not a wholesale replacement
  • Use your judgment to merge changes sensibly

Output On Success

## Specs Synced: <change-name>

Updated main specs:

**<capability-1>**:
- Added requirement: "New Feature"
- Modified requirement: "Existing Feature" (added 1 scenario)

**<capability-2>**:
- Created new spec file
- Added requirement: "Another Feature"

Main specs are now updated. The change remains active - archive when implementation is complete.

Guardrails

  • Read both delta and main specs before making changes
  • Preserve existing content not mentioned in delta
  • If something is unclear, ask for clarification
  • Show what you're changing as you go
  • The operation should be idempotent - running twice should give same result

Read the full file on GitHub · 139 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. 7d ago First seen · 139 lines · 38 tokens per session scan A ea77918baec6

Subscribe to this mod's changes

openspec-sync-specs is a skill published in the GitHub repository mckinsey/agents-at-scale-ark (422 stars, last pushed today), licensed Apache-2.0. It adds 38 tokens to every session and 1,025 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 86% identical to openspec-sync-specs, differing in 21 lines, and is treated as a copy.

Related

Other skills, from other repositories

container-manager-kubernetes-operations

Full operational Kubernetes surface via the container-manager-mcp MCP server — workloads (pods/rollouts/StatefulSets/DaemonSets/ReplicaSets/Jobs/CronJobs), config (ConfigMaps/Secrets/Namespaces/CRDs/patch), networking (Ingress/native Services/NetworkPolicy/DNS), storage (PV/PVC/StorageClass/snapshots/CSI), RBAC…

Knuckles-Team/container-manager-mcp · 189 tokens

k8s-ops

Opinionated multi-step Kubernetes workflows on top of the k8s-mcp server. Encodes tool-sequencing logic and failure-mode decision trees for deploying from a repo, debugging pods/rollouts, performing safe restarts, and auditing cluster posture. Use when the user asks to deploy, diagnose, restart, roll out, or audit…

jingyanjiang/k8s-mcp · 77 tokens

kubernetes-mesh-provisioner

Kubernetes Mesh Provisioner atomic skill. Stands up an RKE2 cluster (server + agents) with Cilium CNI and the NVIDIA GPU device plugin, the Kubernetes parallel of swarm-mesh-provisioner. Idempotent — re-runnable.

Knuckles-Team/container-manager-mcp · 60 tokens

cost-optimization

Optimize cloud costs across AWS, Azure, GCP, and OCI through resource rightsizing, tagging strategies, reserved instances, and spending analysis. Use when reducing cloud expenses, analyzing infrastructure costs, or implementing cost governance policies.

wshobson/agents · 48 tokens

network-rca

Kubernetes network root cause analysis skill powered by Kubeshark MCP. Use this skill whenever the user wants to investigate past incidents, perform retrospective traffic analysis, take or manage traffic snapshots, extract PCAPs, dissect L7 API calls from historical captures, compare traffic patterns over time, detect…

kubeshark/kubeshark · 163 tokens

linkerd-patterns

Implement Linkerd service mesh patterns for lightweight, security-focused service mesh deployments. Use when setting up Linkerd, configuring traffic policies, or implementing zero-trust networking with minimal overhead.

wshobson/agents · 41 tokens