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Token Optimization: Running OpenClaw Efficiently with Kimi K2.5

February 17, 2026· 8 min read

By Irfad Imtiaz, Director of Technology at My Legal Academy


Running OpenClaw costs money — AI providers charge by the token. But there's a massive difference between spending $300/month and $30/month, and most of that difference comes down to smart model selection.

This article covers token optimization: how to run OpenClaw efficiently, which models to use for which tasks, and how Kimi K2.5 offers an excellent option for cost-conscious deployments.

TL;DR: Use Claude Opus for complex tasks and a cheaper model (Sonnet, Flash, or Kimi) for routine messages. The hybrid approach cuts costs 60-80% without noticeable quality loss. Most law firms can run OpenClaw for $25-80/month.


Understanding AI Costs

AI models charge by "token" — roughly, a word or piece of a word. A typical conversation might use 500-2,000 tokens.

Current pricing (February 2026):

Provider Model Input Output Notes
Anthropic Claude Opus 4.5 $15/M $75/M Best quality, expensive
Anthropic Claude Sonnet 4.5 $3/M $15/M Good balance
OpenAI GPT-4 Turbo $10/M $30/M Strong competitor
Google Gemini 1.5 Pro $7/M $21/M Good, cheaper
Google Gemini Flash $0.35/M $1.05/M Fast, very cheap
Moonshot Kimi K2.5 $0.60/M $2/M Strong, very cheap

M = million tokens

What This Means in Practice

A typical law firm running OpenClaw might use:

Monthly costs at different usage levels (without Antigravity):

Model Light Medium Heavy
Claude Opus 4.5 $150-300 $400-700 $1,000+
Claude Sonnet 4.5 $30-60 $80-150 $200-400
Kimi K2.5 $5-15 $20-40 $60-100
Gemini Flash $2-5 $8-15 $20-40

The difference is dramatic. But is cheaper worse?


Quality vs. Cost: The Real Trade-off

Here's what I've found testing different models for law firm intake:

Claude Opus 4.5 (Best Quality)

Strengths:

Best for:

Claude Sonnet 4.5 (Good Balance)

Strengths:

Best for:

Kimi K2.5 (Budget Option)

Kimi K2.5 is from Moonshot AI, a Chinese company. It's surprisingly capable for its price point.

Strengths:

Weaknesses:

Best for:

Gemini Flash (Cheapest)

Strengths:

Weaknesses:

Best for:


The Hybrid Approach

The smartest optimization isn't picking one model — it's using different models for different tasks.

Configuration

In OpenClaw, you can configure which model handles which tasks:

## Model Routing

Client-facing conversations: Claude Opus 4.5
- All WhatsApp messages
- Email responses
- Website chat

Background tasks: Kimi K2.5 or Gemini Flash
- Heartbeat monitoring
- Email summarization
- Internal alerts
- Data extraction

How to Set This Up

  1. In OpenClaw settings, go to AI Configuration
  2. Set your default model (e.g., Claude Sonnet for balance)
  3. Override for specific tasks:
    • New lead conversation → Claude Opus
    • Heartbeat tasks → Gemini Flash
    • Document summarization → Kimi K2.5

This approach typically cuts costs 60-70% while maintaining quality where it matters.


Kimi K2.5: A Closer Look

Kimi deserves special attention because it offers the best cost-to-quality ratio for many use cases.

Setting Up Kimi

  1. Create an account at Moonshot AI or Kimi's platform
  2. Get API access (international access available)
  3. Generate an API key
  4. In OpenClaw, add Kimi as an AI provider:
    • Provider: Moonshot/Kimi
    • API Key: [your key]
    • Model: kimi-k2.5

When to Use Kimi

Good use cases:

Avoid for:

Kimi Quality Tips

If using Kimi, optimize your SOUL.md for clarity:

## For Kimi Optimization

Use extremely clear, structured instructions:
- Numbered steps work better than prose
- Explicit "do X, then do Y, then do Z"
- Avoid ambiguity
- Include example responses

Kimi follows rules well but doesn't improvise as elegantly as Claude.

Reducing Token Usage

Beyond model selection, you can reduce tokens used:

1. Shorter SOUL.md

Every conversation includes your SOUL.md in context. A 5,000-word SOUL.md costs tokens on every message.

Optimization: Trim unnecessary sections. Remove redundant instructions. Use concise language.

Before: "When you encounter a situation where..." (10 words) After: "If..." (1 word)

2. Efficient Conversation History

OpenClaw includes recent conversation history in each request. Long conversations = more tokens.

Configuration:

## Context Settings

Include last 5 messages in context (not full history)
Summarize conversations longer than 10 exchanges
Clear context on new topics

3. Compressed Responses

Configure OpenClaw to give shorter responses:

## Response Style

Keep responses concise:
- 1-3 sentences for simple acknowledgments
- 2-5 sentences for explanations
- Avoid unnecessary pleasantries
- Get to the point

4. Batch Heartbeat Tasks

Instead of separate API calls for each Heartbeat check:

Before: Check email → Check calendar → Check leads (3 API calls) After: Single prompt: "Check email, calendar, and leads. Report findings." (1 API call)


Cost Monitoring

Track your costs to avoid surprises:

In OpenClaw

Enable usage tracking in Settings:

Alert Thresholds

Configure alerts:

Alert if:
- Daily tokens > 500,000
- Weekly cost projection > $100
- Single conversation > 10,000 tokens (indicates problem)

Monthly Review

Review monthly usage patterns:


Choosing Your AI Provider

Different providers offer different trade-offs. Here's how to decide:

OpenRouter gives you access to multiple models through one account:

Cost: $25-100/month typical for law firms

Option 2: Anthropic Direct

For firms that want the best quality and enterprise features:

Cost: $50-300/month typical

Option 3: Kimi/Moonshot

For cost-sensitive firms willing to accept slightly lower quality:

Cost: $15-50/month typical

Option 4: Self-Hosted Models

Advanced option: run open-source models on your own infrastructure. Tools like Ollama let you run LLaMA or Mistral locally.

Pros: No per-token costs, full data control Cons: Requires technical expertise, quality limitations

Most firms won't need this, but it exists.


Practical Recommendations

If Money Is No Object

Use Claude Opus 4.5 for everything through Antigravity (while free) or paid Anthropic API. Quality is worth it.

If Budget-Conscious

Hybrid approach:

Expect 60-70% cost reduction vs. Opus-only.

If Extremely Cost-Sensitive

Kimi K2.5 for most tasks, Claude only for complex situations. Optimize SOUL.md for Kimi's strengths.

Expect 80%+ cost reduction vs. Opus-only.

My Recommendation

Start with: Claude Sonnet 4.5 via OpenRouter as your default model.

Upgrade to Opus for complex intake conversations (sensitive family law, high-value PI cases).

Consider Kimi if you're processing 200+ conversations daily and want to minimize costs.

Monitor your usage for the first month, then adjust based on your specific patterns.


Series Navigation

This is Article 9 of The Zero-Terminal OpenClaw Framework.

  1. What Is OpenClaw? — The complete introduction
  2. OpenClaw vs ChatGPT vs Copilot — Which AI for your firm
  3. The Easiest OpenClaw Setup — Zero-terminal deployment with Antigravity
  4. Deploy in 15 Minutes — Railway template walkthrough (manual method)
  5. Connect Your Channels — WhatsApp, email, Slack
  6. SOUL.md Mastery — Legal compliance templates
  7. 20 Automations Every Firm Needs — Practical use cases
  8. The MCP Playbook — CRM and tool integrations
  9. Token Optimization — You are here
  10. Security Done Right — Attorney-client privilege

← Previous: The MCP Playbook

Next →: Security Done Right

Frequently Asked Questions

Is Kimi K2.5 good enough for legal work?

For routine tasks yes. Kimi handles structured intake, document summarization, and notifications well. For nuanced conversations requiring empathy (family law, emotional situations), Claude Opus is noticeably better.

How much does AI actually cost per conversation?

At Claude Opus rates, roughly $0.10-0.15 per conversation. With Kimi, about $0.002 per conversation. With Antigravity free preview? Zero.

What happens when Antigravity ends?

Three options: pay for Antigravity, switch to direct Anthropic API ($100-500/month for most firms), or use hybrid approach with Kimi for routine tasks and Claude only for complex conversations ($30-100/month).

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