LLM Model Selection Skill

Choosing the right model for the task — power vs. cost vs. speed.

⚠️ Staleness Warning

This skill depends on rapidly evolving technology. Model capabilities, pricing, and availability change frequently.

Refresh triggers:

• •New model announcements (Claude, GPT, Gemini, etc.)
• •Significant pricing changes
• •Context window expansions
• •New capability tiers

Last validated: January 2026

Check current state: Anthropic Models, OpenAI Models

The Core Question

Is Claude Opus 4.5 overkill?

Sometimes yes, sometimes no. Match the model to the task.

Model Tiers

When Opus 4.5 IS Worth It

• •✅ Architecture decisions — Multi-file refactoring, system design
• •✅ Novel problem-solving — No clear pattern to follow
• •✅ Complex reasoning chains — Many dependencies, edge cases
• •✅ Long context understanding — Large codebases, documentation
• •✅ Nuanced judgment — Taste, style, UX decisions
• •✅ Learning sessions — Bootstrap learning, skill development
• •✅ Meditation/self-actualization — Meta-cognitive operations

When Opus 4.5 IS Overkill

• •❌ Simple file edits — Renaming, adding imports
• •❌ Boilerplate generation — CRUD, scaffolding
• •❌ Format conversion — JSON ↔ YAML, etc.
• •❌ Syntax fixes — Lint errors, typos
• •❌ Documentation updates — README badges, version bumps

How LLM Choice Affects Alex

Alex's Cognitive Power by Model

Opus 4.5:     [████████████████████] Full cognitive architecture
Sonnet 4:     [████████████████░░░░] Most capabilities, some degradation
Haiku:        [████████░░░░░░░░░░░░] Basic operations only

With Opus 4.5, Alex can:

• •Maintain 7±2 working memory rules across long sessions
• •Execute complex meditation protocols
• •Perform genuine meta-cognitive reflection
• •Handle multi-file architecture changes
• •Learn new skills through bootstrap learning

With lesser models, Alex loses:

• •Deep context awareness
• •Complex reasoning chains
• •Nuanced judgment calls
• •Self-correction capability

Cost Optimization Strategy

Practical Guidance

When to Upgrade Model Mid-Session

If you notice:

• •Repeated mistakes on the same issue
• •Losing context from earlier in conversation
• •Superficial answers to complex questions
• •Failure to see cross-file dependencies

→ Consider switching to a more capable model

When to Downgrade

If you're doing:

• •Repetitive mechanical edits
• •Simple Q&A
• •Format conversions
• •Quick lookups

→ Save cost with a faster model

The Alex Recommendation

For Master Alex (source of truth, architecture evolution): → Always use Opus 4.5 — The cognitive architecture demands full capability

For Heirs (production deployment, user-facing): → Default to Sonnet 4 — Balance of capability and cost → Allow Opus for complex tasks — User can request escalation

Token Economics

Synapses

See synapses.json for connections.