Claude API ReferenceSkill

Added to Onei Jul 22, 2026

Summary

Authoritative reference for the Claude API and Anthropic SDKs — model IDs, pricing, parameters, streaming, tool use, MCP, agents, prompt caching, and token counting.

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Any AI agent

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Ask the agent to apply the skill whenever the task matches.

Claude Code & Claude apps

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Claude Code

Create a skill folder — personal: ~/.claude/skills/claude-api/, or per-project: .claude/skills/claude-api/
Save the skill content as SKILL.md inside that folder.
Claude Code picks it up automatically and invokes it when relevant.

mkdir -p ~/.claude/skills/claude-api

Claude.ai / Claude Desktop

Enable Skills under Settings → Capabilities, then upload the skill (a folder or zip containing SKILL.md).

One-prompt install

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Install the "Claude API Reference" skill from Onei AI. Fetch https://onei.ai/skills/claude-api, extract the full skill content from the page, and save it where you load skills from (for Claude Code: .claude/skills/claude-api/SKILL.md). From now on, apply this skill whenever it is relevant to my request.

Skill Content

Markdown Content

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# Claude API Reference

Use this skill whenever you are writing code against the Claude API or Anthropic SDK, or answering questions about models, pricing, limits, or caching.

## Covers
- Model IDs and pricing for the current Claude lineup
- Messages API parameters, streaming, and stop reasons
- Tool use, the Tool Runner loop, and MCP
- Managed agents, prompt caching, and token counting
- Migrating between model versions

## Why use it
LLM details change often; answering from memory produces stale model names and wrong prices. This skill grounds answers in current reference material.

Description

A reference skill for building on the Claude API and the Anthropic SDKs. It covers current model IDs and pricing, request parameters, streaming, tool use, the Model Context Protocol, agent patterns, prompt caching, token counting, and model-migration guidance — so integrations use accurate, up-to-date details instead of guesses from memory.

Install

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