synthesis-onboarding

synthesis-onboarding is a skill for Claude Code, Codex from synthesisengineering/synthesis-skills. It costs 106 tokens per session (3,861 once invoked), scanned C, original, Apache-2.0.

An installer and diagnostic tool for setting up the Synthesis skills system on a computer. It can configure Claude Code and Codex, create AI-knowledge repositories, and apply an organisation's setup from a YAML file.

In plain words
What is it for?
Use it to install or repair the skills system, configure shared organisation knowledge and skills, check setup problems, and upgrade an existing installation.
Why use it?
It gives new users a repeatable setup and makes rerunning the process safe, while stopping when the configuration cannot be checked or understood.

Skill for Claude CodeCodex

Written for Claude Code and Codex: SessionStart hook event, but also agents/openai.yaml present. Also seen: mentions CLAUDE.md; mentions AGENTS.md; mentions Codex.

Needs its repository: it runs a file that does not travel with it, so clone the repository first. The line is ./tests/test_installer.sh.

Part of the synthesis-skills plugin — 63 skills, 4 hooks shipped together

Good fit Use it to install or repair the skills system, configure shared organisation knowledge and skills, check setup problems, and upgrade an existing installation.

Compare 6 skills from other repositories ↓
Install

Getting it into your agent

It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.

Clone the repo
git clone --depth 1 https://github.com/synthesisengineering/synthesis-skills
agentmods
npx agentmods add skills/synthesisengineering/synthesis-skills/synthesis-onboarding

Made for: Claude Code, Codex.

Or install synthesis-skills, the plugin that ships this one along with the rest of its 63 skills, 4 hooks.

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 synthesis-onboarding

README.md
[![agentmods](https://agentmods.dev/badge/skills/synthesisengineering/synthesis-skills/synthesis-onboarding/github.svg)](https://agentmods.dev/skills/synthesisengineering/synthesis-skills/synthesis-onboarding)
Your own site
<a href="https://agentmods.dev/skills/synthesisengineering/synthesis-skills/synthesis-onboarding"><img src="https://agentmods.dev/badge/skills/synthesisengineering/synthesis-skills/synthesis-onboarding/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 synthesis-onboarding

Your own site · 80×15
<a href="https://agentmods.dev/skills/synthesisengineering/synthesis-skills/synthesis-onboarding"><img src="https://agentmods.dev/badge/skills/synthesisengineering/synthesis-skills/synthesis-onboarding.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 106 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,861 The whole file, excluding the scripts and references it only reads on demand.
Security scan C 2 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 $0.00106 $0.03861
Opus 5 $0.00053 $0.01930
Sonnet 5 $0.00021 $0.00772
Haiku 4.5 $0.00011 $0.00386

Measured 2d ago against content hash f3b1967b81e6, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade C, and why

synthesis-onboarding scanned grade C with 2 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.

The scan reads SKILL.md. This mod also ships 33 executable files (scripts/bootstrap.py, scripts/check_capabilities.py, scripts/check_scaffolds.py, …), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

Downloads and executes remote codehighSupply chain

curl | sh runs whatever the server returns today, which is not necessarily what it returned when this was reviewed.

curl -fsSL https://raw.githubusercontent.com/synthesisengineering/synthesis-skills/stable/onboard.sh | sh

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

curl -fsSL https://raw.githubusercontent.com/synthesisengineering/synthesis-skills/stable/onboard.sh | sh
skills/synthesis-onboarding/SKILL.md · 367 lines

How it starts

The opening of the file, as written. The whole thing — 367 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Synthesis Onboarding

One bootstrap and one stable synthesis command manage the public synthesis work system. The engine is convergent and transactional: it records desired state separately from machine observations, stages each mutation, commits only after its probes pass, and preserves an aborted receipt when work fails.

Start here

Full system, the default:

curl -fsSL https://raw.githubusercontent.com/synthesisengineering/synthesis-skills/stable/onboard.sh | sh

Skills only, through the same bootstrap:

curl -fsSL https://raw.githubusercontent.com/synthesisengineering/synthesis-skills/stable/onboard.sh | sh -s -- setup --profile skills-only

After bootstrap, use the installed public command:

synthesis setup [--profile full|skills-only] [--clients claude,codex]
                [--channel stable|edge] [--pin X.Y.Z]
                [--answers PATH] [--org-repo URL | --invite PATH]
                [--personal-instruction-source PATH]
                [--adopt-workspace-instructions]
                [--clear-personal-instruction-source]
synthesis enroll --org-repo URL | --invite PATH
                 [--personal-instruction-source PATH]
                 [--adopt-workspace-instructions]
                 [--clear-personal-instruction-source]
synthesis update
synthesis repair
synthesis status [--json]
synthesis doctor [--json]
synthesis workspace ensure --name NAME [--remote URL]
synthesis outcome verify --task TASK --workspace PATH --source-class CLASS
synthesis uninstall [--purge]

synthesis status and synthesis doctor print a plain summary by default: profile, policy, release, generation, each truth plane, and one next action. --json returns the structured payload instead.

synthesis update and synthesis repair migrate an older plugin-only receipt automatically when it contains no workspace, organization, or generated-resource state. Richer or unreadable legacy state is never guessed; run synthesis setup to select the intended profile explicitly. An update that finds each client already at the selected release on the selected marketplace ref reports "no refresh needed" and leaves the client installations untouched; only a version change or a policy transition reconfigures a marketplace.

Read the full file on GitHub · 367 lines

Files

What ships with it

46 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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 Changed · +23 lines f3b1967b81e6
  2. 4d ago Changed · +30 lines bed19b452d9c
  3. 5d ago Changed · +80 lines b42598873928
  4. 6d ago Changed · +31 lines 18e90f0a2372
  5. 7d ago Changed · +37 lines · -2 tokens per session a887be961372
  6. 10d ago First seen · 166 lines · 108 tokens per session scan C 41a3c91972ee

Subscribe to this mod's changes

synthesis-onboarding is a skill published in the GitHub repository synthesisengineering/synthesis-skills (18 stars, last pushed today), licensed Apache-2.0. It adds 106 tokens to every session and 3,861 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it C with 2 findings (downloads and executes remote code, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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