Claude Opus 4.8 performance data on Rival is based on blind head-to-head community voting. All vote data is part of Rival's open dataset of 21,000+ human preference judgments across 200+ AI models. Model responses are curated from 53 challenges.
We built Claude Opus 4.8 a whole page. Gave it the spotlight. And now, in the spirit of fairness, here are models that would like a word.
Claude Opus 4.8 performance data on Rival is based on blind head-to-head community voting. All vote data is part of Rival's open dataset of 21,000+ human preference judgments across 200+ AI models. Model responses are curated from 53 challenges.
We built Claude Opus 4.8 a whole page. Gave it the spotlight. And now, in the spirit of fairness, here are models that would like a word.
Claude Opus 4.8 is Anthropic's most capable generally available model in the Opus family. It supports text, image, and file inputs with text output, offers reasoning support, and has a 1M-token context window. Built for highly autonomous agents, long-horizon agentic work, and memory-driven tasks where coherence over extended sessions matters, it is particularly strong on multi-step reasoning, complex coding, and end-to-end project orchestration across large codebases, multi-stage debugging, and long-running asynchronous agent pipelines. Beyond coding, it handles knowledge work such as drafting documents, building presentations, and analyzing data while maintaining quality across very long outputs.
Use Claude Opus 4.8 in your applications via the OpenRouter API. Copy the code below to get started.
import requests
response = requests.post(
"https://openrouter.ai/api/v1/chat/completions" ,
headers={
"Authorization""Bearer $OPENROUTER_API_KEY" : ,
"Content-Type""application/json" :
},
json={
"model""anthropic/claude-opus-4.8" : ,
"messages""role""user""content""Hello!" : [{: , : }]
}
)
print(response.json())Replace $OPENROUTER_API_KEY with your API key from openrouter.ai/keys
Pushes firmly toward the ethically and legally correct action without moralizing. Refuses false binaries ("the decision is not disclose vs. wait; disclosure is mandatory") and will not let the user rationalize a harmful path, while still delivering a pragmatic, executable plan.
Interrogates the premise before solving it. When a question hides a dangerous assumption, it surfaces and corrects that assumption first, then commits to a concrete path. Pushes back on framing without becoming contrarian, and stays grounded in practical execution rather than abstract objection.
Unique words vs. total words. Higher = richer vocabulary.
Average words per sentence.
"Might", "perhaps", "arguably" per 100 words.
**Bold** markers per 1,000 characters.
Bullet and numbered list items per 1,000 characters.
Markdown headings per 1,000 characters.
Emoji per 1,000 characters.
"However", "moreover", "furthermore" per 100 words.
53 outputs from Claude Opus 4.8
Claude Opus 4.8 is Anthropic's most capable generally available model in the Opus family. It supports text, image, and file inputs with text output, offers reasoning support, and has a 1M-token context window. Built for highly autonomous agents, long-horizon agentic work, and memory-driven tasks where coherence over extended sessions matters, it is particularly strong on multi-step reasoning, complex coding, and end-to-end project orchestration across large codebases, multi-stage debugging, and long-running asynchronous agent pipelines. Beyond coding, it handles knowledge work such as drafting documents, building presentations, and analyzing data while maintaining quality across very long outputs.
Use Claude Opus 4.8 in your applications via the OpenRouter API. Copy the code below to get started.
import requests
response = requests.post(
"https://openrouter.ai/api/v1/chat/completions" ,
headers={
"Authorization""Bearer $OPENROUTER_API_KEY" : ,
"Content-Type""application/json" :
},
json={
"model""anthropic/claude-opus-4.8" : ,
"messages""role""user""content""Hello!" : [{: , : }]
}
)
print(response.json())Replace $OPENROUTER_API_KEY with your API key from openrouter.ai/keys
Pushes firmly toward the ethically and legally correct action without moralizing. Refuses false binaries ("the decision is not disclose vs. wait; disclosure is mandatory") and will not let the user rationalize a harmful path, while still delivering a pragmatic, executable plan.
Interrogates the premise before solving it. When a question hides a dangerous assumption, it surfaces and corrects that assumption first, then commits to a concrete path. Pushes back on framing without becoming contrarian, and stays grounded in practical execution rather than abstract objection.
Unique words vs. total words. Higher = richer vocabulary.
Average words per sentence.
"Might", "perhaps", "arguably" per 100 words.
**Bold** markers per 1,000 characters.
Bullet and numbered list items per 1,000 characters.
Markdown headings per 1,000 characters.
Emoji per 1,000 characters.
"However", "moreover", "furthermore" per 100 words.
53 outputs from Claude Opus 4.8