Smart Model Routing for IronClaw

Status: Implemented Author: Microwave Date: 2026-02-19

What

Automatic model selection based on request complexity. The router analyzes each user message and selects an appropriate model tier (flash/standard/pro/frontier), then maps that tier to a configured model.

Why

1. Cost optimization — Simple requests ("hi", "what time is it") don't need expensive models
2. User experience — Simple requests return faster with lightweight models
3. NEAR AI native — Default backend uses NEAR AI inference where costs vary by model
4. Zero-config value — Users benefit immediately without configuration
5. Not just power users — Everyone gets smart defaults, power users can override

How

Architecture

User Message
     │
     ▼
┌──────────────────┐
│ Pattern Overrides │  ← Fast-path for obvious cases (greetings, security audits)
└────────┬─────────┘
         │ no match
         ▼
┌──────────────────┐
│ Complexity Scorer │  ← 13-dimension analysis
└────────┬─────────┘
         │ score 0-100
         ▼
┌──────────────────┐
│   Tier Mapping   │  ← 0-15: flash, 16-40: standard, 41-65: pro, 66+: frontier
└────────┬─────────┘
         │ tier
         ▼
┌──────────────────┐
│  Model Selection │  ← Currently: cheap provider (Flash/Standard/Pro) vs primary (Frontier)
└────────┬─────────┘    Target: per-tier model mapping via config
         │
         ▼
    LLM Provider

Complexity Scorer (13 Dimensions)

Each dimension produces a 0-100 score. Weighted sum determines total.

Multi-dimensional boost: +30% when 3+ dimensions score above threshold.

Tier Boundaries

Pattern Overrides

Fast-path rules that bypass scoring for obvious cases:

# Force flash tier
- "^(hi|hello|hey|thanks|ok|sure|yes|no)$"
- "^what.*(time|date|day)"

# Force frontier tier
- "security.*(audit|review|scan)"
- "vulnerabilit(y|ies).*(review|scan|check|audit)"

# Force pro tier
- "deploy.*(mainnet|production)"

Configuration

Note: The current implementation supports smart routing via NEARAI_CHEAP_MODEL and SMART_ROUTING_CASCADE env vars, plus domain_keywords on SmartRoutingConfig. The full llm.routing YAML schema below is the target design — not all knobs are wired yet.

Default (zero-config):

llm:
  routing:
    enabled: true  # default

Power user overrides (target schema):

llm:
  routing:
    enabled: true
    tiers:
      flash: "claude-3-5-haiku-latest"
      standard: "claude-sonnet-4-5-latest"
      pro: "claude-sonnet-4-5-latest"
      frontier: "claude-opus-4-5-latest"
    thinking:
      pro: "low"
      frontier: "medium"
    overrides:
      - pattern: "my-custom-pattern"
        tier: "pro"
    domain_keywords:  # Custom keywords for your domain
      - "mycompany"
      - "myproduct"
      - "internal-tool"

If domain_keywords is not set, uses DEFAULT_DOMAIN_KEYWORDS which covers common web3/infra terms.

Disable routing (pin model):

llm:
  routing:
    enabled: false
  model: "claude-opus-4-5"

Bring your own keys:

llm:
  backend: anthropic
  api_key: "sk-..."
  routing:
    enabled: true  # still works with external providers

Integration Points

1. RoutingProvider — New wrapper implementing LlmProvider trait (like FailoverProvider)
2. Scorer — Pure function, no I/O, fast (~1ms)
3. Config schema — Extend LlmConfig with routing section
4. Telemetry — Log routing decisions for observability

Model Agnosticism

Critical: No hardcoded model names in the router logic itself.

• Tier→model mappings come from config
• Default mappings use -latest patterns where supported
• NEAR AI backend handles actual model resolution
• Router only knows about tiers

Layers of Control

Implementation Plan

1. Port scorer to Rust (src/llm/smart_routing.rs)
2. Implement router wrapper (src/llm/smart_routing.rs)
3. Extend config schema (src/config.rs)
4. Wire into provider creation (src/llm/mod.rs)
5. Add telemetry/logging
6. Tests with real conversation samples
7. Codex + Gemini security review
8. Documentation updated (this spec)

Expected Outcomes

• 50-70% cost reduction for typical usage patterns
• Faster responses for simple requests
• Zero config required for default benefits
• Full control for power users who want it