agentmods.dev

create-atomic-schema

create-atomic-schema is a skill for Claude Code from Eigenwise/atomic-agents. It costs 89 tokens per session (1,492 once invoked), scanned A, original, MIT.

A guide for defining the typed input and output data that an Atomic Agents agent or tool accepts and returns. It covers field descriptions, documentation, validation rules, and error forms.

In plain words
What is it for?
Use it to create or change an Atomic Agents schema, add fields, define validation, or separate successful and failed results.
Why use it?
It removes guesswork when setting the contract between an agent or tool and the code that calls it. Clear schemas also help the framework validate data and describe expected output to the language model.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the atomic-agents plugin — 7 skills, 2 agents shipped together

not rated 6.3krepo +5 8d ago A scan SkillSpector: pass 89 tokens original MIT

Good fit Use it to create or change an Atomic Agents schema, add fields, define validation, or separate successful and failed results.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/eigenwise/atomic-agents/create-atomic-schema
View source ↗ Eigenwise/atomic-agents eigenwise.github.io
About the project

Atomic Agents is a lightweight, modular framework for assembling AI agents and applications from single-purpose components such as agents, tools, and context providers. It is for developers building maintainable agentic AI pipelines with reusable, composable parts and structured outputs. The catalogue entries provide agent skills, instructions, settings, and related development workflows for the framework.

Eigenwise/atomic-agents · 6,319 stars · on GitHub · eigenwise.github.io

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.

Any agent
npx skills add Eigenwise/atomic-agents --skill create-atomic-schema
Clone the repo
git clone --depth 1 https://github.com/Eigenwise/atomic-agents

Made for: Claude Code.

Or install atomic-agents, the plugin that ships this one along with the rest of its 7 skills, 2 agents.

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 create-atomic-schema

README.md
[![agentmods](https://agentmods.dev/badge/skills/eigenwise/atomic-agents/create-atomic-schema/github.svg)](https://agentmods.dev/skills/eigenwise/atomic-agents/create-atomic-schema)
Your own site
<a href="https://agentmods.dev/skills/eigenwise/atomic-agents/create-atomic-schema"><img src="https://agentmods.dev/badge/skills/eigenwise/atomic-agents/create-atomic-schema/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 create-atomic-schema

Your own site · 80×15
<a href="https://agentmods.dev/skills/eigenwise/atomic-agents/create-atomic-schema"><img src="https://agentmods.dev/badge/skills/eigenwise/atomic-agents/create-atomic-schema.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 89 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,492 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. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 $0.00089 $0.01492
Opus 5.5 $0.00036 $0.00597
Sonnet 5.5 $0.00018 $0.00298
Haiku 4.5 $0.00009 $0.00149

Measured 2mo ago against content hash f4a77c1e6101, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

create-atomic-schema 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 2mo 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.

claude-plugin/atomic-agents/skills/create-atomic-schema/SKILL.md · 138 lines

How it starts

The opening of the file, as written. The whole thing — 138 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Create an Atomic Agents Schema

Author a BaseIOSchema pair (input and/or output) that becomes the contract between an agent or tool and its caller. The framework enforces docstrings on every subclass, and Instructor flows field descriptions into the LLM prompt — so the schema is part of the prompt, not just typing.

For deep material (validators, discriminated unions, error envelopes), the authority is ../framework/references/schemas.md. This skill is the action-oriented path: clarify → write → validate.

When this fires vs the umbrella framework skill

  • This skill: the user is creating or modifying a specific schema — e.g. "design the output schema for the planner agent", "add a field to WeatherInput", "split the result into success and failure variants".
  • framework skill: the user is asking about Atomic Agents in general or doing something other than authoring schemas.

Phase 1 — Clarify

Ask only what is not already obvious from context. Bundle into one message; do not interrogate one-at-a-time.

  1. Caller — is this for an AtomicAgent, a BaseTool, both (an agent that emits a tool-input schema), or a nested sub-schema?
  2. Direction — input only, output only, or a paired Input/Output?
  3. Fields — what fields does the caller need, with which types? (Required vs optional, defaults, constraints.)
  4. Failure modes — can this legitimately fail? If yes, plan a typed error variant rather than raising. See ../framework/references/schemas.md → "Error-schema pattern".

If the user is mid-conversation about an existing schema, skip questions answered in context.

Phase 2 — Write

Place schema(s) where they will be imported from. Conventional locations:

  • <project>/agents/<agent_name>/schemas.py — agent-owned schemas
  • <project>/tools/<tool_name>_tool.py — tool I/O lives next to the tool
  • <project>/schemas/<topic>.py — schemas shared across multiple components

Required ingredients on every schema

  • Subclass BaseIOSchema (not BaseModel).
  • A non-empty class docstring — the framework raises at import otherwise. Write it for the LLM, because Instructor uses it as the schema's description.
  • Every Field(...) carries a description= written for the LLM.
  • Use Literal[...] for closed sets before reaching for Enum — flatter JSON Schema, easier for Instructor.

Read the full file on GitHub · 138 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. 2mo ago First seen · 138 lines · 89 tokens per session scan A f4a77c1e6101

Subscribe to this mod's changes

create-atomic-schema is a skill published in the GitHub repository Eigenwise/atomic-agents (6,319 stars, last pushed 8d ago), licensed MIT. It adds 89 tokens to every session and 1,492 once invoked, about $0.0004 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.

Building agentsaiartificial-intelligencelarge-language-modellarge-language-modelsllmsopenai
Related

create-atomic-schema compared with skills from other repositories

create-atomic-schema next to 6 skills from other repositories
ModTypeStarsLast pushLicenceScanTokensWorks with
create-atomic-schemaEigenwise/atomic-agentsSkill6.3k8d agoMITA89Claude Code
alfworld-device-operatorzjunlp/SkillNetSkill1.4k4d agoMITA93Claude Code, Codex
alfworld-inventory-managementzjunlp/SkillNetSkill1.4k4d agoMITA70Claude Code, Codex
alfworld-object-locatorzjunlp/SkillNetSkill1.4k4d agoMITA66Claude Code, Codex
scienceworld-measurement-takerzjunlp/SkillNetSkill1.4k4d agoMITA81Claude Code, Codex
scienceworld-threshold-evaluatorzjunlp/SkillNetSkill1.4k4d agoMITA69Claude Code, Codex
webshop-attribute-verifierzjunlp/SkillNetSkill1.4k4d agoMITA119Claude Code, Codex