Claude Opus 4.8
Sharper Agentic Judgement · 4x Fewer Code Flaws
Sharper, more reliable judgement on agentic tasks, 4x fewer code flaws than Opus 4.7, Online-Mind2Web 84%, native 1M context — at the same price as Opus 4.7 ($5/$25 per MTok)
Key Highlights
4x less likely than Opus 4.7 to allow flaws in code — a step-change in production code reliability
84% task success on computer-use / browser-agent workloads, with sharper, more reliable agentic judgement
Highest score recorded and the first model to break 10% overall on the all-pass standard
$5 input / $25 output per MTok — identical to Opus 4.7, no price increase
Coding Leap: Reliability You Can Ship
From long-horizon autonomy to complex tool calls, Opus 4.8 makes agentic code work dramatically more dependable — far fewer defects to catch downstream
4x Fewer Code Flaws vs 4.7
Opus 4.8 is 4x less likely than Opus 4.7 to allow flaws in code, meaning fewer review cycles and fewer regressions reaching production
CursorBench Across Every Effort Level
Exceeds all prior Opus models on CursorBench across every effort level — more headroom whether you optimize for latency or depth
Sharper Agentic Judgement
Sharper and more reliable when performing agentic tasks: better decisions about when to act, when to verify, and when to ask
Super-Agent: End-to-End Completion
On the Super-Agent benchmark, Opus 4.8 is the only model to complete every case end-to-end without dropping the task
Online-Mind2Web 84%
84% success on computer-use / browser-agent tasks — reads dense UI, navigates, and acts reliably across multi-step flows
⭐ Improved Honesty
Improved honesty means fewer confident-but-wrong claims about its own work — it flags uncertainty instead of papering over it
Strong Multimodal & Long-Context Handling
Opus 4.8 pairs strong multimodal understanding with better long-context handling across native 1M context — send images directly via API, no parameter switch needed
Computer-use Agents Reading Dense Screenshots
Strong multimodal grounding lets agents read UI detail and act reliably, contributing to the 84% Online-Mind2Web result
Long-Context Stability
Better long-context handling across native 1M context — large repos, long transcripts, and multi-document tasks stay coherent
Document & Chart Understanding
Reads charts, tables, and document layouts as part of multimodal reasoning, extracting structure and detail in one pass
Legal Agent Benchmark Leadership
Highest score recorded and first to break 10% on the all-pass standard — evidence of reliable judgement on demanding domain tasks
Platform Capabilities
Effort Tier: xhigh
The xhigh tier between high and max offers a finer-grained reasoning-depth vs latency trade-off. Carried forward into Opus 4.8
/ultrareview Deep Code Review
Claude Code command for an independent review session that runs through changes end-to-end, finding bugs and design issues
Adaptive Thinking
Adaptive thinking lets Claude self-allocate reasoning depth across long tasks instead of a fixed token budget
Fast Mode Default
Opus 4.8 is now the Claude Code Fast Mode default (replacing 4.7), bringing sharper judgement to everyday fast iterations
Migration Guide (⭐ Key)
Upgrading from Opus 4.7 to Opus 4.8 is a drop-in replacement (change model ID to claude-opus-4-8) — here is what to keep in mind
1. Drop-in Model ID Swap
Change the model id from claude-opus-4-7 to claude-opus-4-8 — no other config change required
2. Expect Sharper Judgement
Opus 4.8 brings sharper agentic judgement and improved honesty; re-validate prompts and harnesses to take advantage of the more reliable decisions
3. Use Adaptive Thinking
Use thinking={type:"adaptive"} with the effort parameter; the legacy thinking={type:"enabled", budget_tokens:N} form remains deprecated
4. 1M Context & Fast Mode
Native 1M context carries over; Opus 4.8 is now the Fast Mode default. A 1M-context variant id (claude-opus-4-8[1m]) is also available
client.messages.create(
model="claude-opus-4-7",
thinking={"type": "enabled", "budget_tokens": 10000}
)
client.messages.create(
model="claude-opus-4-8",
thinking={"type": "adaptive"},
effort="xhigh" # available since 4.7
)
vs GPT-5.4 / Gemini 3.1 Pro
Same-tier flagship comparison (Anthropic has not published a full SWE-bench Pro figure for the newest Opus — the headline gains are agentic reliability and 4x fewer code flaws)
| Metric | Opus 4.8 | GPT-5.4 | Gemini 3.1 Pro |
|---|---|---|---|
| Code reliability | 4x fewer flaws vs 4.7 | See OpenAI | See Google |
| Input $ / MTok | $5 | See OpenAI | See Google |
| Output $ / MTok | $25 | See OpenAI | See Google |
| Context window | Native 1M | 272K / 1M beta | 1M |
| Computer-use (Online-Mind2Web) | 84% | — | — |
Get Opus 4.8 via QCode.cc
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Same Price $5/$25
QCode.cc bills at Anthropic's official rates with no multiplier markup
Full Support for New Parameters
Full pass-through of xhigh effort, adaptive thinking, and other Opus 4.8 parameters
Drop-in Switch 4.7 to 4.8
Change model ID from claude-opus-4-7 to claude-opus-4-8, no other config changes needed
China-Direct with Failover
Multi-node smart routing + circuit breakers, avoiding instability of direct official API access from within China
Try Opus 4.8 Now
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