harness-sdk: Skill for Claude Code

.agents/skills/strands/skills/scaffold-agent/SKILL.md

scaffold-agent is a skill for Claude Code from strands-agents/harness-sdk. It costs 54 tokens per session (159 once invoked), scanned A, original, Apache-2.0.

A guide for starting a new Strands agent or adding Strands to an existing Python or TypeScript project. It focuses on creating the smallest runnable setup that matches the project's language, package manager, model provider, and conventions.

In plain words
What is it for?
Use it to initialize a Strands project, choose between its higher-level harness and lower-level software kit, or add a basic agent to an existing codebase.
Why use it?
It prevents an initial setup from growing unnecessary tools, storage, deployment, or infrastructure. When model credentials are unavailable, it provides a way to check the setup without making a paid model request.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: installed under .agents/ (shared by several agents).

This is strands-agents/harness-sdk's own configuration. It tells Claude Code how to work on harness-sdk 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 harness-sdk configures →

Part of the strands plugin — 5 skills, 1 MCP server shipped together

About the project

Strands Agents is an open-source SDK for building and running AI agents in Python and TypeScript. Developers use it to create agents with model providers, tools, lifecycle controls, memory, sessions, streaming, tracing, and evaluations, and the catalogue includes add-ons for its agent-building workflow.

strands-agents/harness-sdk · 8,607 stars · on GitHub · strandsagents.com

Reuse

Borrowing it

Nothing to install: this file belongs to strands-agents/harness-sdk. 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/strands-agents/harness-sdk/main/.agents/skills/strands/skills/scaffold-agent/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/strands-agents/harness-sdk

Made for: Claude Code.

Or install strands, the plugin that ships this one along with the rest of its 5 skills, 1 MCP server.

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 scaffold-agent

README.md
[![agentmods](https://agentmods.dev/badge/skills/strands-agents/harness-sdk/scaffold-agent/github.svg)](https://agentmods.dev/skills/strands-agents/harness-sdk/scaffold-agent)
Your own site
<a href="https://agentmods.dev/skills/strands-agents/harness-sdk/scaffold-agent"><img src="https://agentmods.dev/badge/skills/strands-agents/harness-sdk/scaffold-agent/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 scaffold-agent

Your own site · 80×15
<a href="https://agentmods.dev/skills/strands-agents/harness-sdk/scaffold-agent"><img src="https://agentmods.dev/badge/skills/strands-agents/harness-sdk/scaffold-agent.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 54 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 159 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 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 5.1 $0.00054 $0.00159
Opus 5.5 $0.00022 $0.00064
Sonnet 5.5 $0.00011 $0.00032
Haiku 4.5 $0.00005 $0.00016

Measured today against content hash 67e800500101, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-02, from the pricing page.

Security

Grade A, and why

scaffold-agent 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 today.

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.

.agents/skills/strands/skills/scaffold-agent/SKILL.md · 11 lines

What it actually says

Scaffold a Strands agent

Read the shared Strands skill and the scaffold guide completely, then create the smallest runnable agent that matches the project's language, package manager, model provider, and existing conventions.

Do not add tools, persistence, deployment, or infrastructure unless the requested first behavior needs them. Run the entrypoint when credentials are available; otherwise validate imports, types, and configuration without making a billable model call.

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. today First seen · 11 lines · 54 tokens per session scan A 67e800500101

Subscribe to this mod's changes

scaffold-agent is a skill published in the GitHub repository strands-agents/harness-sdk (8,607 stars, last pushed today), licensed Apache-2.0. It adds 54 tokens to every session and 159 once invoked, about $0.0002 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 2026-10-02.

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