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.
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.
npx skills add Eigenwise/atomic-agents --skill frameworkgit clone --depth 1 https://github.com/Eigenwise/atomic-agentsWrote 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.
[](https://agentmods.dev/skills/eigenwise/atomic-agents/framework)<a href="https://agentmods.dev/skills/eigenwise/atomic-agents/framework"><img src="https://agentmods.dev/badge/skills/eigenwise/atomic-agents/framework/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.
<a href="https://agentmods.dev/skills/eigenwise/atomic-agents/framework"><img src="https://agentmods.dev/badge/skills/eigenwise/atomic-agents/framework.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00074 | $0.02258 |
| Opus 5.5 | $0.00030 | $0.00903 |
| Sonnet 5.5 | $0.00015 | $0.00452 |
| Haiku 4.5 | $0.00007 | $0.00226 |
Grade A, and why
framework 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.
How it starts
The opening of the file, as written. The whole thing — 156 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Atomic Agents Framework
Atomic Agents is a lightweight Python framework for building LLM applications with typed, structured input and output. It layers on top of Instructor and Pydantic so every interaction between user, agent, tool, and context is a validated schema.
This skill orients Claude on the framework and routes to focused reference files as the task requires.
Core abstractions
| Concept | Class | Role |
|---|---|---|
| Schema | BaseIOSchema |
Typed input/output contract — every agent/tool I/O is one |
| Agent | AtomicAgent[In, Out] |
LLM-backed transformer from input schema to output schema |
| Config | AgentConfig |
Wires client, model, history, prompt, roles, API params |
| Prompt | SystemPromptGenerator |
Three-section prompt: background, steps, output_instructions |
| History | ChatHistory |
Conversation state, serializable, token-counted |
| Tool | BaseTool[In, Out] |
Deterministic capability the agent can invoke |
| Context | BaseDynamicContextProvider |
Dynamic section injected into the system prompt at runtime |
All communication between these uses BaseIOSchema subclasses with docstring-required descriptions.
Canonical imports
from atomic_agents import (
AtomicAgent, AgentConfig,
BasicChatInputSchema, BasicChatOutputSchema,
BaseIOSchema, BaseTool, BaseToolConfig,
)
from atomic_agents.context import (
ChatHistory, Message,
SystemPromptGenerator, BaseDynamicContextProvider,
)
# Optional: MCP interop
from atomic_agents.connectors.mcp import fetch_mcp_tools, MCPTransportType
Do not use legacy paths like atomic_agents.lib.base.* or atomic_agents.agents.base_agent — those were retired. Import from the top-level package where possible.
Minimum viable agent
import os, instructor, openai
from atomic_agents import AtomicAgent, AgentConfig, BasicChatInputSchema, BasicChatOutputSchema
from atomic_agents.context import ChatHistory
client = instructor.from_openai(openai.OpenAI(api_key=os.environ["OPENAI_API_KEY"]))
agent = AtomicAgent[BasicChatInputSchema, BasicChatOutputSchema](
config=AgentConfig(
client=client,
model="gpt-5-mini",
history=ChatHistory(),
)
)
reply = agent.run(BasicChatInputSchema(chat_message="Hello"))
print(reply.chat_message)
What ships with it
11 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.
- references/agents.md 5.4 KB
- references/context-providers.md 5.3 KB
- references/hooks.md 5.7 KB
- references/memory.md 6.9 KB
- references/orchestration.md 5.3 KB
- references/project-structure.md 4.3 KB
- references/prompts.md 3.1 KB
- references/providers.md 6.6 KB
- references/schemas.md 5.9 KB
- references/testing.md 4.9 KB
- references/tools.md 8.5 KB
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.
- 2mo ago First seen · 156 lines · 74 tokens per session scan A 79dc389da4f8
framework is a skill published in the GitHub repository Eigenwise/atomic-agents (6,319 stars, last pushed 8d ago), licensed MIT. It adds 74 tokens to every session and 2,258 once invoked, about $0.0003 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.
framework compared with skills from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| frameworkEigenwise/atomic-agents | Skill | 6.3k | 8d ago | MIT | A | 74 | Claude Code |
| alfworld-device-operatorzjunlp/SkillNet | Skill | 1.4k | 4d ago | MIT | A | 93 | Claude Code, Codex |
| alfworld-inventory-managementzjunlp/SkillNet | Skill | 1.4k | 4d ago | MIT | A | 70 | Claude Code, Codex |
| alfworld-object-locatorzjunlp/SkillNet | Skill | 1.4k | 4d ago | MIT | A | 66 | Claude Code, Codex |
| scienceworld-measurement-takerzjunlp/SkillNet | Skill | 1.4k | 4d ago | MIT | A | 81 | Claude Code, Codex |
| scienceworld-threshold-evaluatorzjunlp/SkillNet | Skill | 1.4k | 4d ago | MIT | A | 69 | Claude Code, Codex |
| webshop-attribute-verifierzjunlp/SkillNet | Skill | 1.4k | 4d ago | MIT | A | 119 | Claude Code, Codex |