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March 20, 202610 min readClaw Mart Team

Best AI Models for OpenClaw: Which Provider to Use?

Best AI Models for OpenClaw: Which Provider to Use?

Best AI Models for OpenClaw: Which Provider to Use?

Look, I'll save you the three weeks of trial and error I went through: the AI model you plug into OpenClaw matters more than almost any other decision you'll make when building your agent. Pick the wrong one and you'll watch your agent burn through tokens, loop endlessly, and produce garbage. Pick the right one and suddenly you've got something that actually works — reliably, affordably, and without you babysitting every step.

I've tested essentially every major model provider inside OpenClaw at this point, across dozens of skill configurations and use cases. This is the honest breakdown of what works, what doesn't, and why.

Why the Model Choice Matters So Much in OpenClaw

Most people new to OpenClaw treat the model selection like picking a paint color — cosmetic, reversible, not that important. That's wrong. The model is the engine. OpenClaw's architecture is designed to give your agent structure, memory, tool access, and planning scaffolding, but the underlying model is what actually reasons through each step, decides which tool to call, interprets the results, and figures out what to do next.

Here's the thing: not all models are created equal when it comes to agentic work. A model that's great at writing a blog post or answering trivia might be absolutely terrible at the kind of structured, multi-step, tool-calling reasoning that OpenClaw demands. I've seen models that score well on generic benchmarks completely fall apart when asked to execute a five-step OpenClaw skill with two tool calls and a conditional branch.

The differences show up in specific, predictable ways:

  • Tool call formatting: Some models reliably output clean, parseable tool calls. Others randomly inject markdown, forget required parameters, or hallucinate tool names that don't exist.
  • Instruction adherence over long contexts: Your OpenClaw system prompt plus skill definitions plus conversation history can get long. Some models "forget" their instructions by step four.
  • Reasoning under ambiguity: When a tool returns unexpected data, does the model adapt intelligently or does it loop, panic, or hallucinate?
  • Cost per task completion: A model that takes 15 steps (and 15 API calls) to do what another model does in 4 steps isn't just slower — it's nearly 4x more expensive.

The Tier List: Models Ranked for OpenClaw

After months of testing, here's where things actually stand. I'm ranking these specifically for OpenClaw agentic performance, not general chatbot quality.

Tier 1: The Reliable Workhorses

Anthropic Claude 3.5 Sonnet (and Claude 3.7 Sonnet)

This is the one. If you're just getting started with OpenClaw and you want the highest probability of things working correctly on the first try, use Claude 3.5 Sonnet. Full stop.

Why? Claude handles structured tool calling better than anything else I've tested. It follows system prompts with almost eerie consistency, even deep into multi-step agent runs. It rarely hallucinates tool parameters. When it encounters an error from a tool response, it usually does the intelligent thing: it re-reads the error, adjusts its approach, and retries with corrected parameters.

In OpenClaw specifically, Claude 3.5 Sonnet nails the XML-style tool formatting that many skills rely on. Here's what a typical tool call looks like when Claude is powering your agent:

<tool_call>
  <name>web_search</name>
  <parameters>
    <query>latest quarterly earnings AAPL 2026</query>
    <max_results>5</max_results>
  </parameters>
</tool_call>

Clean. Parseable. No random commentary injected into the middle of the XML. No "Sure! I'd be happy to search for that!" preamble before the tool call. It just does the thing.

Claude 3.7 Sonnet with extended thinking is even better for complex, multi-step skills where the agent needs to plan several moves ahead, but it's more expensive and slower. For most OpenClaw use cases, 3.5 Sonnet hits the sweet spot.

The downside: Rate limits. If you're running multiple agents or high-frequency skills, you'll hit Anthropic's rate limits faster than you'd like. For production-scale deployments, you'll need to either negotiate higher limits or implement queuing.

OpenAI GPT-4o

Solid second choice. GPT-4o is good at tool calling (OpenAI pioneered the function-calling format, after all), handles long contexts well, and is fast. It's slightly more verbose than Claude — it likes to "think out loud" more, which burns extra tokens — but it gets the job done.

Where GPT-4o falls behind Claude in OpenClaw: instruction following over long runs. Around step 8-10 of a complex skill chain, I've noticed GPT-4o starts to drift. It'll subtly reinterpret its goal, skip a tool it should have called, or summarize when it should have been precise. Claude stays locked in.

GPT-4o's tool calling format in OpenClaw looks like this:

{
  "name": "web_search",
  "arguments": {
    "query": "latest quarterly earnings AAPL 2026",
    "max_results": 5
  }
}

Both formats work perfectly in OpenClaw — the platform handles the translation. You're choosing based on model quality, not compatibility.

Tier 2: Specialized Use Cases

OpenAI o1 / o1-pro

The o1 family is fascinating for OpenClaw but niche. These models are dramatically better at complex reasoning — if your skill involves multi-step logic, mathematical computation, code generation, or anything that benefits from "thinking longer before answering," o1 outperforms everything else.

The catch: it's slow and expensive. An o1-pro call in an agent loop can take 30-60 seconds and cost 10-20x what a Sonnet call costs. For an agent that needs 8 steps to complete a task, you might be looking at 5+ minutes and several dollars per run.

My recommendation: use o1 as a "planner" model within OpenClaw. Set it as the model for your planning step, then use Claude or GPT-4o for execution steps. OpenClaw's skill configuration makes this straightforward:

skill: research_report
planner:
  model: openai/o1
  task: "Create a step-by-step research plan"
executor:
  model: anthropic/claude-3.5-sonnet
  task: "Execute each research step using available tools"
synthesizer:
  model: anthropic/claude-3.5-sonnet
  task: "Compile findings into a coherent report"

This hybrid approach gives you o1's superior planning without paying o1 prices for every single tool call and synthesis step.

Google Gemini 1.5 Pro

Gemini's massive context window (up to 2M tokens) makes it interesting for OpenClaw skills that need to process large documents, long conversation histories, or extensive tool outputs. If your agent needs to ingest a 200-page PDF and then answer questions about it while using tools, Gemini can hold all of that in context without chunking or retrieval.

In practice, though, Gemini's tool calling is less reliable than Claude or GPT-4o. I've seen it output malformed JSON about 15-20% of the time in complex skill chains, which causes parsing failures and agent loops. It's getting better with each update, but right now I'd only recommend it for specific large-context use cases, not as your default.

Tier 3: Open Source (Proceed with Caution)

Llama 3.1 405B, Qwen 2.5 72B, Command R+

I want to love open-source models for OpenClaw. I really do. The cost savings would be incredible, and the ability to self-host means no rate limits ever.

Reality check: they're not there yet for reliable agentic work. I've tested Llama 3.1 405B (via Together AI and locally via vLLM) extensively in OpenClaw, and the failure modes are frustrating:

  • Tool calls are malformed roughly 30-40% of the time
  • The model frequently ignores available tools and tries to answer from memory instead
  • Multi-step planning degrades rapidly after 3-4 steps
  • Instruction adherence in system prompts is inconsistent

Qwen 2.5 72B is actually the best of the open-source bunch for tool use — it was specifically trained with tool-calling data — but it still can't match Claude or GPT-4o for reliability.

If you're committed to open source, here's my advice: use it for simple, single-tool skills only. Don't try to build complex multi-step agents on open-source models right now. You'll waste more time debugging than you'll save on API costs.

Practical Setup: Configuring Your Model in OpenClaw

Here's how to actually set this up. OpenClaw makes model swapping relatively painless, which is one of its best features.

Your basic provider configuration:

# openclaw.config.yaml
providers:
  anthropic:
    api_key: ${ANTHROPIC_API_KEY}
    default_model: claude-3-5-sonnet-20241022
    max_retries: 3
    timeout: 60

  openai:
    api_key: ${OPENAI_API_KEY}
    default_model: gpt-4o
    max_retries: 3
    timeout: 45

For individual skills, you override the model at the skill level:

# skills/research_agent.yaml
name: deep_research
model: anthropic/claude-3-5-sonnet-20241022
temperature: 0.1
max_tokens: 4096
tools:
  - web_search
  - url_reader
  - note_taker
system_prompt: |
  You are a research agent. Your job is to thoroughly research the given topic using your available tools. Always cite your sources. Do not fabricate information.

Notice the temperature setting. For agentic work in OpenClaw, I keep temperature between 0.0 and 0.2. Higher temperatures introduce randomness that kills reliability. You want your agent to be boring and consistent, not creative and unpredictable.

The Cost Reality

Let me give you real numbers from actual OpenClaw runs, because this is where people get burned.

Simple skill (3-5 steps, one tool):

  • Claude 3.5 Sonnet: ~$0.02-0.05 per run
  • GPT-4o: ~$0.03-0.08 per run
  • o1: ~$0.15-0.40 per run

Complex skill (10-15 steps, multiple tools, planning + execution):

  • Claude 3.5 Sonnet: ~$0.15-0.35 per run
  • GPT-4o: ~$0.20-0.50 per run
  • o1 (all steps): ~$2.00-5.00+ per run

Hybrid approach (o1 for planning, Claude for execution):

  • ~$0.40-0.80 per run

The hybrid approach is roughly 70% cheaper than using o1 for everything, with maybe a 10% quality decrease. That's almost always worth it.

Debugging Model-Specific Issues

Here's the stuff nobody tells you. When your OpenClaw agent fails, the model is usually the culprit, and each model fails in characteristic ways.

Claude failure mode: Gets overly cautious. Sometimes refuses to call a tool because it decides the task might involve sensitive information. Fix: be explicit in your system prompt that the agent has permission to use all available tools.

GPT-4o failure mode: Drifts off-task and starts "helping" in ways you didn't ask for. You ask it to extract data from a webpage and it decides to also summarize, analyze, and provide recommendations. Fix: add explicit "Do ONLY what is requested. Do not add additional analysis or commentary" to your system prompt.

o1 failure mode: Overthinks simple tasks. You ask it to call a search tool and it writes a three-paragraph internal monologue about search strategy before making the call, burning tokens and time. Fix: use o1 only for steps that actually require deep reasoning.

Open source failure mode: Outputs tool calls embedded in conversational text instead of in the structured format OpenClaw expects. The model says "I'll search for that now" and then puts the tool call inside a markdown code block instead of using the proper format. Fix: very aggressive system prompt engineering with explicit examples of the exact output format required. Even then, expect ~30% failure rates.

My Actual Recommendation

If you're just starting out with OpenClaw and want to minimize frustration, here's exactly what I'd do:

  1. Start with Claude 3.5 Sonnet as your default model. It has the best reliability-to-cost ratio for agentic work, and OpenClaw's tool-calling architecture works exceptionally well with Claude's structured output.

  2. Set temperature to 0.1 for all agentic skills. Bump to 0.3-0.5 only for creative output tasks.

  3. Use the hybrid approach for complex skills. o1 for planning, Claude for execution. The config example above shows you how.

  4. Don't go open source until you're experienced with OpenClaw and have a specific cost-driven reason. The debugging time will eat any savings.

  5. If you don't want to configure all of this from scratch, honestly, just grab Felix's OpenClaw Starter Pack on Claw Mart. It's $29 and comes with pre-configured skills that already have the optimal model settings, temperature tuning, and system prompts dialed in. I spent weeks figuring out the right configurations through trial and error — Felix packaged up what works and saved you that headache. The research agent skill alone in that pack is worth the price because the system prompts and tool configurations are already battle-tested. You can always modify them later once you understand why each setting is what it is.

  6. Monitor your costs from day one. Set budget limits in your provider configuration and use OpenClaw's built-in logging to track token usage per skill. Costs sneak up on you fast when you're iterating.

What's Next

The model landscape changes fast. Claude 4 is presumably on the horizon. GPT-5 is coming. Open-source models are improving rapidly — Llama 4 might actually be good enough for basic agentic work.

But right now, today, the practical answer is Claude 3.5 Sonnet for most OpenClaw work, GPT-4o as your backup, and o1 for complex planning steps. That combination will get you 80% of the way to reliable agents without burning through your API budget.

Stop overthinking the model choice. Pick Claude, build your first skill, ship it, and iterate from there. The best model is the one you actually build something with.

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