Anthropic's mid-tier Claude model, which Anthropic describes as its best combination of speed and intelligence. It succeeds Sonnet 5 at the same $2 / $10 rate, with a 1M-token context and half the cache-read price, and sits below Opus 5.5.
Pick it if
you want Claude at half of Opus 5.5's per-token price
you resend long prompts; cache hits bill at 5% of input
your prompts need a 1M-token window at the standard rate
Skip it if
Haiku 5.5 handles your high-volume classification or routing more cheaply
your code forces tool use or sets temperature; both return errors
Gemini 4 Argon is Google's flagship reasoning model, built for complex software engineering, with a 1M-token context shared by input and output. Its introductory $2 / $10 rate undercuts Gemini 3.1 Pro on output until it doubles to $4 / $20 on 2026-12-01.
Pick it if
want Google's flagship reasoning model with low, medium or high thinking
need video, audio or PDF input alongside images in one context
send long prompts: no long-context surcharge and $0.10 cached input
Skip it if
you plan heavy volume after 2026-12-01, when rates double to $4 / $20
Gemini 3.8 Flash at $0.75 / $3.75 already covers your workload
FAQ
Which is better, Claude Sonnet 5.5 or Gemini 4 Argon?
On Terminal-Bench 4.0, as each maker reports it, Claude Sonnet 5.5 scores 70.6% and Gemini 4 Argon 57.4%. These are each maker's own numbers, not a controlled head-to-head; the spec table lists every benchmark both publish.
Which is cheaper, Claude Sonnet 5.5 or Gemini 4 Argon?
Claude Sonnet 5.5 and Gemini 4 Argon list the same input and output prices. On a coding-agent session (2M tokens in, 60,000 out) Claude Sonnet 5.5 costs $4.60 and Gemini 4 Argon $4.60.
Can I switch between Claude Sonnet 5.5 and Gemini 4 Argon mid-task?
Yes. In an Octomind session, /model octohub:claude-sonnet-5-5 and /model octohub:gemini-4-argon switch models without losing the conversation, so you can draft on one and review on the other.
Try either model
Switch between models inside the same Octomind session.