compare/Claude Opus 5.5vsDecisions

Claude Opus 5.5 vs Decisions

Pricing, context window, capabilities, and release date — pulled from each provider's public docs. Both are available via the same AIgateway OpenAI-compatible endpoint; flip the model string to switch.

RUN BOTH LIVE

Paste a prompt. Watch them race.

Both models stream in parallel through your own AIgateway key. Tokens, latency, and cost update as they arrive.

Sign in to runLive streaming uses your own key. It's free to sign up.
 Claude Opus 5.5
anthropic/claude-opus-5.5
Decisions
openai/decisions
ProviderAnthropicOpenAI
FamilyClaude 4
Modalitytexttext
Context window1,000,000 tok1,050,000 tok
Max output128,000 tok32,768 tok
Released2026-09-232026-10-26
Input price$4.00 /1M$0.100 /1M
Output price$20.00 /1M$0.0000 /1M
Cache read——
Toolsyes—
Streamingyesyes
Visionyes—
JSON modeyes—
Reasoningyes—
Prompt caching——
Claude Opus 5.5
anthropic/claude-opus-5.5
Full spec →

Claude Opus 5.5 is Anthropic's model for long-running agentic coding and knowledge work. It combines a one million token context window with adaptive thinking that is always on, a 128K token maximum output, and a medium default effort level.

Strengths
  • General-purpose chat
  • Long context
  • Tool use
Decisions
openai/decisions
Full spec →

Decisions uses GPT-6 Luna to evaluate shared text or image evidence against typed questions. It returns probabilities, fixed choices, or rubric scores for low-latency classification, routing, and prioritization workflows.

Strengths
  • General-purpose chat
  • Long context
  • Tool use
SWITCH BETWEEN THEM

One key, both models, one line different.

# pip install aigateway-py openai
# aigateway-py: sub-accounts, evals, replays, jobs, webhook verify.
# openai SDK: chat/embeddings/images/audio — drop-in compat per our SDK's own guidance.
from openai import OpenAI

client = OpenAI(
    base_url="https://api.aigateway.sh/v1",
    api_key="sk-aig-...",
)

# Try Claude Opus 5.5
client.chat.completions.create(
    model="anthropic/claude-opus-5.5",
    messages=[{"role":"user","content":"hello"}],
)

# Try Decisions — same client, same key
client.chat.completions.create(
    model="openai/decisions",
    messages=[{"role":"user","content":"hello"}],
)
Get an AIgateway keyAdd a third model

Compare with another

Gemini 4 Argon vs Claude Opus 5.5
google/gemini-4-argon · anthropic/claude-opus-5.5
Gemini 4 Argon vs Decisions
google/gemini-4-argon · openai/decisions
Claude Opus 5.5 vs Claude Sonnet 5.5
anthropic/claude-opus-5.5 · anthropic/claude-sonnet-5.5
Claude Opus 5.5 vs Deepseek-V4.1-Flash-1017
anthropic/claude-opus-5.5 · deepseek/deepseek-v4.1-flash-1017
Claude Opus 5.5 vs Grok 4.7
anthropic/claude-opus-5.5 · xai/grok-4.7
Claude Opus 5.5 vs MiniMax M3.1 Flash
anthropic/claude-opus-5.5 · minimax/m3.1-flash
Claude Opus 5.5 vs Qwen3.8-Max
anthropic/claude-opus-5.5 · alibaba/qwen3.8-max
Claude Opus 5.5 vs GLM-5.3-Prime
anthropic/claude-opus-5.5 · zai-org/glm-5.3-prime
Claude Opus 5.5 vs Pareto
anthropic/claude-opus-5.5 · unbiased/pareto