⚡ 2026 Developer Toolkit

Claude Toolkit

19 curated agent templates for Claude Code, Cursor, Copilot, and MCP. Includes live Prompt Caching ROI Calculator, official 2026 Anthropic pricing models, and .ant.yaml generator.

Executive Summary: The Claude Toolkit provides ready-to-use configuration files for enterprise AI code generation. It covers Anthropic's latest frontier models (Claude Sonnet 5, Claude 3.7 Sonnet, Claude Opus 5, Claude 3.5 Haiku) with built-in prompt caching mathematics that cut recurring multi-turn token costs by up to 90%.

⚡ Anthropic Prompt Caching & Token Cost ROI CalculatorVendor Verified

Calculate multi-turn agent token cost reduction using Anthropic's 90% cache read discount.

Cached Prompt / Context45,000 tokens
CLAUDE.md, System Prompts, Tool Specs, Monorepo Context
Turns per Session20 turns
Break-even is achieved on Turn 2
Output Tokens / Turn800 tokens
Code completions, patch blocks, response text
Monthly Sessions500 runs
Developer CLI invocations or automated agent jobs
Standard Uncached Cost
$980
Per month without cache headers
Cached Architecture Cost
$221.75
With Anthropic prompt_caching
Estimated Monthly Savings
$758.25
77.4% Cost Reduction
Break-Even Turn
Turn #2
Immediate profit on 2nd turn

🛠️ Interactive Config BuilderUpdated

⌨️ Claude Code & ant CLI5🌐 Anthropic API & Prompt Caching4🖱️ Cursor2🤖 GitHub Copilot1✦ Gemini CLI & Antigravity2🏄 Windsurf (Cascade)1🦘 Roo Code & Cline2⚡ Zed AI Editor1🔌 MCP Server Ecosystem1
✅ 100% Free to use✅ Zero telemetry or sign-up✅ Aligned to 2026 official vendor docs
⌨️ Claude Code & ant CLI🌐 Anthropic API & Prompt Caching🖱️ Cursor🤖 GitHub Copilot✦ Gemini CLI & Antigravity🏄 Windsurf (Cascade)🦘 Roo Code & Cline⚡ Zed AI Editor🔌 MCP Server Ecosystem
⌨️

Claude Code & ant CLI

Source: docs.anthropic.com (2026)
5 configs

Anthropic's CLI execution environment. Configured with 5-minute & 1-hour prompt caching controls, 'Monitor' tools, and the new `ant` YAML CLI setup. Supporting Claude Sonnet 5, 3.7 Sonnet, and Opus 5.

.ant.yaml
▾
Configuration file for the `ant` CLI tool. Manages fast environments, agent versions, and prompt cache ttl.
CLAUDE.md
▾
Project memory — read at every session start. Keep under 200 lines. Optimized for the 1M token context limit.
.claude/settings.json
▾
Permissions, hooks, and behavior control. Project-level (committed to git). Use settings.local.json for personal overrides (gitignored).
.claude/agents/security-reviewer.md
▾
Custom sub-agent — specialized AI persona invoked for security auditing. Configured with Claude Sonnet 5.
.claude/.mcp.json
▾
MCP server config for Claude Code sessions. Defines which MCP servers are available. Project-scoped (committed) or global (~/.claude/.mcp.json).
🌐

Anthropic API & Prompt Caching

Source: Anthropic Messages API Docs (2026)
4 configs

Production integration snippet utilizing Anthropic Prompt Caching with cache_control checkpoints, 128k output limits, and extended thinking.

src/agents/client.ts
▾
Anthropic client snippet with prompt caching breakpoints and extended thinking configuration.
src/agents/conversation-compaction.ts
▾
Anthropic Messages API Conversation Compaction (September 14, 2026 beta). Auto-compresses message history to prevent context overflow.
.claude/managed-agents-policy.json
▾
Managed Agents 'auto' permission policy configuration (September 10, 2026 release).
claude-enterprise-soe-aoe.yaml
▾
Enterprise Claude SOE (Standard Operating Environment) and AOE (AI Operations Engineering) configuration.
🖱️

Cursor

Source: cursor.com/docs, cursor.directory
2 configs

AI-native code editor. Uses .cursor/rules/ folder with .mdc files (Markdown Context) for modular, glob-filtered rules.

.cursor/rules/project-context.mdc
▾
Always-on project context. Tells Cursor what your stack is, so it generates code matching your exact setup.
.cursor/rules/typescript-standards.mdc
▾
Scoped to TypeScript/TSX files only via glob pattern. Enforces type safety rules.
🤖

GitHub Copilot

Source: docs.github.com, code.visualstudio.com
1 configs

GitHub's AI pair programmer in VS Code. Uses .github/copilot-instructions.md for project-wide rules and .github/instructions/ for path-specific overrides.

.github/copilot-instructions.md
▾
Project-wide Copilot instructions — automatically applied to all suggestions and chat interactions. Commit to git for team-wide standards.
✦

Gemini CLI & Antigravity

Source: geminicli.com, Google DeepMind docs
2 configs

Google's AI coding tools. Gemini CLI for terminal workflows, Antigravity for IDE agent sessions. Both read GEMINI.md for context.

GEMINI.md
▾
Project context file — equivalent to CLAUDE.md. Read at session start. Place at project root or ~/.gemini/GEMINI.md for global rules.
.gemini/settings.json
▾
Project-level Gemini settings. Controls model, permissions, and behavior. ⚠️ Warning: If you use both Gemini CLI and Antigravity, they share ~/.gemini/GEMINI.md — be careful of config pollution.
🏄

Windsurf (Cascade)

Source: windsurf docs, dev.to
1 configs

Agentic IDE powered by Cascade. Uses .windsurfrules (legacy) or .windsurf/rules/ folder for modular configs. Keep rules under 6,000 characters to avoid truncation.

.windsurfrules
▾
Legacy single-file rules — simple and effective. Place at project root. For larger projects, migrate to .windsurf/rules/ folder.
🦘

Roo Code & Cline

Source: github.com/RooVetGit/Roo-Code docs
2 configs

Autonomous coding agent extensions for VS Code. Uses .clinerules or .roomode/ rules for custom agent personas (Architect, Code, Debugger, Security).

.clinerules
▾
Global rule instructions read by Roo Code and Cline on session start.
.roomodes
▾
Custom mode definitions for Roo Code custom personas.
⚡

Zed AI Editor

Source: zed.dev/docs/ai
1 configs

High-performance GPU-accelerated code editor with native Anthropic Claude integration and custom prompt presets.

.zed/settings.json
▾
Project settings for Zed AI sessions. Configures model, assistant context, and inline transformation prompts.
🔌

MCP Server Ecosystem

Source: modelcontextprotocol.io
1 configs

Production Model Context Protocol (MCP) server configurations for Claude Desktop, Claude Code, and Cursor.

claude_desktop_config.json
▾
Standard MCP server setup for web search, persistent memory, and browser testing.

📊 Cross-Tool Cheat Sheet

FeatureClaude Code (ant CLI)CursorManaged Agents APIWindsurf
Primary Config.ant.yaml / CLAUDE.md.cursor/rules/*.mdcsrc/agents/client.ts.windsurfrules
Sandboxing Modelocal / dockerlocal sandboxCloud Native (Managed)local sandbox
Scoped rules.claude/skills/globs in .mdcAgent Instructions.windsurf/rules/
API HeadersNativeNativeprompt-caching-2024-07-31Native
Sub-agents.claude/agents/—Advisor Tool APIs—
MCP config.claude/.mcp.json.cursor/mcp.jsonPre-packaged Toolsmcp_config.json

2026 Enterprise AI Engineering Shift

AI coding workflows have evolved from basic inline completions into multi-agent autonomous engineering loops. Using Anthropic's cache_control: { type: "ephemeral" } and the new .ant.yaml CLI harness, teams can retain 1-million-token contexts across entire monorepos without prohibitive token overhead.

Whether targeting Claude Sonnet 5, Claude 3.7 Sonnet, or Claude Opus 5, prompt caching achieves break-even ROI on the second turn of any agent session. Modular .cursor/rules/*.mdc files and CLAUDE.md files guarantee strict architectural constraints and prevent regressions during high-speed refactoring sprints.

This toolkit provides 19 production-grade templates. All templates are completely free, open-source, and run entirely client-side in your browser.

Frequently Asked Questions

What is the Claude Toolkit?

Claude Toolkit is a free, comprehensive developer suite featuring copy-paste configuration templates (CLAUDE.md, .ant.yaml, .cursorrules, copilot-instructions.md), an interactive CLAUDE.md generator, and an Anthropic Prompt Caching & Token Cost Calculator.

How does Anthropic Prompt Caching work and how much does it save?

Anthropic Prompt Caching allows developers to cache frequently used context, system instructions, and tool definitions for 5 minutes or 1 hour. Subsequent requests read cached tokens at a 90% discount ($0.20/M tokens on Claude Sonnet 5 instead of $2.00/M), cutting multi-turn agent execution costs by up to 90%.

Which Claude models are supported?

Claude Toolkit natively supports Anthropic's frontier lineup: Claude Sonnet 5 (1M context, 128K output, permanent $2/$10 pricing), Claude 3.7 Sonnet (Extended Thinking up to 64K tokens), Claude Opus 5 (deep long-horizon reasoning), and Claude 3.5 Haiku (sub-second tool calling).

Does the toolkit support September 2026 Conversation Compaction & Managed Agents?

Yes, Claude Toolkit includes ready-to-use snippets for the Messages API Conversation Compaction beta (compact-2026-09-04) and Anthropic Managed Agents auto permission policy configurations.

Is the Claude Toolkit free to use?

Yes, 100% free with no sign-up or installation required. All configs, calculations, and templates run locally in your browser.