Anthropic (Claude)

Anthropic builds the Claude model family — the primary and most deeply integrated provider for OpenClaw. Claude models power the core agent loop, tool calling, thinking/reasoning, and vision capabilities that make OpenClaw tick.

Anthropic builds the Claude model family — the primary and most deeply integrated provider for OpenClaw. Claude models power the core agent loop, tool calling, thinking/reasoning, and vision capabilities that make OpenClaw tick. The Claude lineup spans from the lightweight Haiku 3.5 ($0.80/MTok input) up to the flagship Opus 4.6 ($5/MTok input, $25/MTok output). Sonnet models sit in the sweet spot for most OpenClaw users — strong reasoning at $3/MTok input. All models share a 200K context window, and Anthropic's prompt caching system can cut repeat-context costs by up to 90% (cache reads cost just 10% of base input price). Authentication is flexible: use a standard API key for pay-as-you-go billing, or connect via setup-token OAuth if you have a Claude Max/Pro subscription. The OAuth path is particularly popular for heavy users who want predictable monthly costs instead of per-token billing. Anthropic also supports batch API for async workloads at 50% discount, and a new Fast Mode for Opus 4.6 that trades 6x pricing for significantly faster output. For OpenClaw specifically, Anthropic is the default and recommended provider. The native Anthropic Messages API integration is the most battle-tested path, with full support for streaming, tool use, vision, extended thinking, and prompt caching. If you're unsure which provider to start with, start here.

Tags: frontier, claude, api-key, oauth, prompt-caching

Use Cases

  • Primary OpenClaw agent model — powering daily personal assistant workflows with tool use, vision, and extended thinking
  • Code generation and review via Claude Code integration (ACP harness)
  • Document analysis using vision capabilities — screenshots, PDFs, diagrams
  • Complex multi-step reasoning tasks with adaptive thinking mode
  • Cost-optimized batch processing using Batch API for data enrichment pipelines
  • Prompt-cached conversational workflows where system context is large but stable

Tips

  • Use Sonnet 4.5 or 4.6 as your default model — it's the best price/performance ratio for most OpenClaw workloads.
  • Enable prompt caching for system prompts and SOUL.md/AGENTS.md content that stays constant across turns. This can save 50-90% on input costs.
  • For cost-conscious setups, use Haiku 3.5 for heartbeats, cron jobs, and simple classification tasks. Reserve Sonnet/Opus for complex work.
  • Use the Batch API (50% discount) for non-time-sensitive enrichment tasks, data processing, or bulk analysis.
  • Set thinking mode to 'adaptive' to let the model decide when extended reasoning is needed — avoids wasting reasoning tokens on simple requests.
  • Consider Claude Max subscription ($100/mo) + setup-token OAuth if you're consistently spending more than $100/mo on API calls.

Known Issues & Gotchas

  • Rate limits can be aggressive on new API accounts — Tier 1 starts at just 50 RPM. You need to build usage history to unlock higher tiers.
  • Prompt caching has a minimum of 1,024 tokens for the cached block (2,048 for Haiku). Smaller prompts won't benefit.
  • The 5-minute cache TTL is short — if your requests are spaced further apart, cache misses will be common. Consider the 1-hour cache at 2x write cost for less frequent usage.
  • Output tokens are 3-5x more expensive than input tokens across all Claude models. Long-form generation can get costly fast.
  • Extended thinking (reasoning) tokens are billed as output tokens — budget accordingly for complex reasoning tasks.
  • Fast Mode for Opus 4.6 is 6x standard pricing ($30/MTok input, $150/MTok output). Easy to accidentally burn budget.
  • Data residency (US-only inference) adds a 1.1x multiplier on all token categories for Opus 4.6+.
  • Anthropic does not offer embeddings — you'll need a separate provider (Mistral, OpenAI, or local) for memory/RAG.

Alternatives

  • OpenAI (GPT)
  • Amazon Bedrock
  • OpenRouter
  • Ollama (Local)

Community Feedback

Have you tested OpenClaw with Anthropic? I think it's incredible. I have just developed with Claude this week an app to run it on the cloud.

— Reddit r/Anthropic

All the OpenClaw bros are having a meltdown after Anthropic clarified subscription usage rules — but as of February 2025, you can still use Claude accounts to run OpenClaw.

— Reddit r/ClaudeAI

My main tip is to do lots of small tasks instead of doing few large tasks. Small tasks take way less tokens and are usually less buggy.

— Reddit r/ClaudeAI

From December 25 to December 31, Anthropic temporarily doubled usage limits. Starting January 1, usage limits were sharply reduced.

— Reddit r/ClaudeAI

Configuration Examples

Basic Anthropic API key setup

providers:
  anthropic:
    apiKey: sk-ant-api03-xxxxx
    model: anthropic/claude-sonnet-4-6

Claude Max subscription (OAuth setup-token)

providers:
  anthropic:
    setupToken: true
    # Run: openclaw configure --provider anthropic
    # Follow OAuth flow to link your Claude subscription
    model: anthropic/claude-opus-4-6

Cost-optimized multi-model setup

providers:
  anthropic:
    apiKey: sk-ant-api03-xxxxx
    model: anthropic/claude-sonnet-4-5
    # Use Haiku for lightweight tasks
    # Override per-session with /model haiku
thinking: adaptive
reasoningEffort: medium