pydantic-ai-harness
Extend Pydantic AI agents with capabilities from pydantic-ai-harness -- the Coder coding agent, file and shell tools in local or sandboxed workspaces (Modal, E2B, Sprites, smolvm), Code Mode, sub-agents and planning, memory and skills, context compaction, guardrails and spend limits, web research and browsers, hosted SaaS integrations, step persistence, and background agents on Render Workflows. Use when the user mentions pydantic-ai-harness or pydantic_ai_harness, imports a harness capability such as Coder, CodeMode, FileSystem, Shell, SubAgents, Memory, or ToolGuardrail, or wants a Pydantic AI agent that edits files, runs commands or agent-written Python, delegates, remembers, manages long context, stays within limits, or runs model and tool operations as chained Render task runs.
Install
With your agent
Install OMGSkills skill "pydantic/skills:pydantic-ai-harness" into this agent's normal skills directory: call the OMGSkills MCP get_install_plan tool for your agent and run the script it returns (it installs only the pinned commit and verifies SKILL.md), and stop if MCP or the pin is unavailable. Do not overwrite or change existing skills without asking me.
Manual command
git clone https://github.com/pydantic/skills /tmp/skills && ln -s /tmp/skills/skills/pydantic-ai-harness ~/.claude/skills/pydantic-ai-harnessFrom README
Building with Pydantic AI Harness Pydantic AI Harness is the official capability library for Pydantic AI. Core pydantic-ai ships the agent loop and the capabilities that need model or framework support (thinking, web search, MCP, tool search, workspaces, and provider-native compaction); the harness ships optional capabilities for longer, more involved work: a coding stack, sandboxes, delegation, memory, context management, and controls. Harness capabilities go in Agent(capabilities=[...]) and compose with each other and with core capabilities; a few supporting pieces, such as media stores and the ACP server entry point, are used directly instead. This skill covers pydantic-ai-harness. For the core framework -- agents, tools, structured output, hooks, workspaces, and testing -- use the building-pydantic-ai-agents skill.
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