Claude Sonnet 4.6 in OpenClaw: Upgrade Guide and What's Better

Claude Sonnet 4.6 Is Now Natively Supported in OpenClaw

OpenClaw v2026.2.17 added native support for anthropic/claude-sonnet-4-6 across aliases, defaults, and the model catalog. If you're running an older OpenClaw version or manually configured your model string, this guide explains how to upgrade and what you gain.

What's New With Sonnet 4.6 Support

The update isn't just adding a string to a list. The v2026.2.17 release includes:

• Native alias support — You can now reference Sonnet 4.6 via the alias anthropic/claude-sonnet-4-6 and it resolves correctly across all OpenClaw model paths.
• Forward-compat fallback — If your upstream provider catalog doesn't yet expose Sonnet 4.6, OpenClaw falls back gracefully to Sonnet 4.5 rather than erroring out. This means you can configure Sonnet 4.6 safely even before all your providers fully support it.
• GitHub Copilot catalog — Sonnet 4.6 and 4.5 were added to the GitHub Copilot model catalog inside OpenClaw. If you use Copilot as an AI provider, both models are now available.
• Cloud Code Assist compatibility — Tool schema cleaning was updated for Google's Cloud Code Assist, so Claude tool calls work reliably with the newer models via that provider route.

How to Switch to Claude Sonnet 4.6

If you're already running OpenClaw with Claude, switching to Sonnet 4.6 is straightforward:

# Via CLI
openclaw config set model.primary anthropic/claude-sonnet-4-6

# Or in your config file
model:
  primary: anthropic/claude-sonnet-4-6
  fallbacks:
    - anthropic/claude-sonnet-4-5

The fallback chain is important — if Sonnet 4.6 is unavailable or rate-limited, OpenClaw automatically tries Sonnet 4.5. This is especially useful if you use multiple Anthropic API keys with different rate limits.

Should You Upgrade?

Sonnet 4.6 is Anthropic's current recommended model for most agentic tasks. Compared to Sonnet 4.5:

• Better tool use — More reliable function calling and JSON output, which matters for cron jobs and multi-step workflows
• Improved context handling — Better at maintaining coherent context across long conversations
• Stronger reasoning — Noticeably better at complex analytical tasks and multi-step planning
• Same pricing tier — Sonnet 4.6 is in the same price bracket as Sonnet 4.5

For most OpenClaw users, upgrading to Sonnet 4.6 is a no-brainer — same cost, meaningfully better quality.

1M Context Window: The Bigger Opportunity

Alongside the Sonnet 4.6 update, OpenClaw v2026.2.17 also added opt-in support for the 1M context window beta. You can enable it per-model:

model:
  primary: anthropic/claude-sonnet-4-6
  params:
    context1m: true

This maps to the anthropic-beta: context-1m-2025-08-07 header. It's opt-in because not all use cases benefit from it, and it does affect token costs for very long sessions. We cover this in detail in our 1M context window guide.

Multi-Provider Setup: Mixing Models

One underused OpenClaw feature is per-session model overrides. You can run different models for different channels or tasks:

# Use Sonnet 4.6 for main conversations
model:
  primary: anthropic/claude-sonnet-4-6

# Use Haiku for cron jobs (faster, cheaper)
cron:
  model:
    primary: anthropic/claude-haiku-4-5

This kind of fine-grained model routing requires knowing the OpenClaw config schema well — it's one of the areas where expert setup pays off.

Checking Your Current Model

Not sure what model you're currently running? Use the OpenClaw status command:

openclaw status

As of v2026.2.17, cached token counts now appear in /status output, so you can also see how much of your context is being cached — which affects both performance and cost.