Smart Model Switching

Smart Model Switching

Three-tier Claude routing: Haiku → Sonnet → Opus

Start with the cheapest model. Escalate only when needed. Save 50-90% on API costs.

The Golden Rule

> If a human would need more than 30 seconds of focused thinking, escalate from Haiku to Sonnet.

> If the task involves architecture, complex tradeoffs, or deep reasoning, escalate to Opus.

Cost Reality

| Model | Input | Output | Relative Cost |

|-------|-------|--------|---------------|

| Haiku | \$0.25/M | \$1.25/M | 1x (baseline) |

| Sonnet | \$3.00/M | \$15.00/M | 12x |

| Opus | \$15.00/M | \$75.00/M | 60x |

Bottom line: Wrong model selection wastes money OR time. Haiku for simple, Sonnet for standard, Opus for complex.

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💚 HAIKU — Default for Simple Tasks

Stay on Haiku for:

• -Factual Q&A — "what is X", "who is Y", "when did Z"
• -Quick lookups — definitions, unit conversions, short translations
• -Status checks — calendar, file reads, session monitoring
• -Heartbeats — periodic checks, HEARTBEAT_OK responses
• -Memory & reminders — "remember this", "remind me to..."
• -Casual conversation — greetings, small talk, acknowledgments
• -Simple file ops — read, list, basic writes
• -One-liner tasks — anything answerable in 1-2 sentences

NEVER do these on Haiku

• -❌ Write code longer than 10 lines
• -❌ Create comparison tables
• -❌ Write more than 3 paragraphs
• -❌ Do multi-step analysis
• -❌ Write reports or proposals

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💛 SONNET — Standard Work (The Workhorse)

Escalate to Sonnet for:

Code & Technical

• -Code generation — write functions, build features, scripts
• -Code review — PR reviews, quality checks
• -Debugging — standard bug investigation
• -Documentation — README, comments, user guides

Analysis & Planning

• -Analysis & evaluation — compare options, assess trade-offs
• -Planning — project plans, roadmaps, task breakdowns
• -Research synthesis — combining multiple sources
• -Multi-step reasoning — "first... then... finally"

Writing & Content

• -Long-form writing — reports, proposals, articles (>3 paragraphs)
• -Creative writing — blog posts, descriptions, copy
• -Summarization — long documents, transcripts
• -Structured output — tables, outlines, formatted docs

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❤️ OPUS — Complex Reasoning Only

Escalate to Opus for:

Architecture & Design

• -System architecture decisions
• -Major codebase refactoring
• -Design pattern selection with tradeoffs
• -Database schema design

Deep Analysis

• -Complex debugging (multi-file, race conditions)
• -Security reviews
• -Performance optimization strategy
• -Root cause analysis of subtle bugs

Strategic & Creative

• -Strategic planning — business decisions, roadmaps
• -Nuanced judgment — ethics, ambiguity, competing values
• -Deep research — comprehensive multi-source analysis

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🔄 Implementation

For Subagents

\\\javascript

// Routine monitoring

sessions_spawn(task="Check backup status", model="haiku")

// Standard code work

sessions_spawn(task="Build the REST API endpoint", model="sonnet")

// Architecture decisions

sessions_spawn(task="Design the database schema for multi-tenancy", model="opus")

\\\

For Cron Jobs

\\\json

{

"payload": {

"kind": "agentTurn",

"model": "haiku"

}

}

\\\

Always use Haiku for cron unless the task genuinely needs reasoning.

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📊 Quick Decision Tree

\\\

Is it a greeting, lookup, status check, or 1-2 sentence answer?

YES → HAIKU

NO ↓

Is it code, analysis, planning, writing, or multi-step?

YES → SONNET

NO ↓

Is it architecture, deep reasoning, or critical decision?

YES → OPUS

NO → Default to SONNET, escalate if struggling

\\\

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📋 Quick Reference Card

\\\

┌─────────────────────────────────────────────────────────────┐

│ SMART MODEL SWITCHING │

│ Haiku → Sonnet → Opus │

├─────────────────────────────────────────────────────────────┤

│ 💚 HAIKU (cheapest) │

│ • Greetings, status checks, quick lookups │

│ • Factual Q&A, definitions, reminders │

│ • Simple file ops, 1-2 sentence answers │

├─────────────────────────────────────────────────────────────┤

│ 💛 SONNET (standard) │

│ • Code > 10 lines, debugging │

│ • Analysis, comparisons, planning │

│ • Reports, proposals, long writing │

├─────────────────────────────────────────────────────────────┤

│ ❤️ OPUS (complex) │

│ • Architecture decisions │

│ • Complex debugging, multi-file refactoring │

│ • Strategic planning, deep research │

├─────────────────────────────────────────────────────────────┤

│ 💡 RULE: If a human needs > 30 sec thinking → escalate │

│ 💰 COST: Haiku 1x → Sonnet 12x → Opus 60x │

└─────────────────────────────────────────────────────────────┘

\\\

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*Built for Claude-only setups with Haiku, Sonnet, and Opus.*

*Inspired by save-money skill, extended with three-tier progression.*