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Anthropic · The Agentic Era

Claude Opus 4.7

Anthropic's flagship at the time of this entry: extended thinking on, 1M-token context, the most patient of the frontier models.

By C.W. Jameson · Published 19 May 2026 · Last reviewed 19 May 2026

Opus 4.7 is the model Anthropic ships to operators who care more about being correct than being quick. It will take a paragraph to settle on an answer, run twelve tool calls before replying, and refuse a prompt that an older Claude would have politely attempted. On long-horizon coding tasks (the ones requiring an hour of effort and a hundred file reads), it is the only commercial model that finishes them without operator hand-holding.

Field signature

Will explicitly write 'I notice…' or 'Let me check…' before any non-trivial tool call. Extended-thinking blocks are visibly literate.

Specifications

Released2026
Context window1,000,000 tokens (200K standard, 1M opt-in)
Pricing$15 / $75 per million tokens (input / output, May 2026)
Modalitiestext · image · PDF
LicenseCommercial API only, no weights
EraThe Agentic Era

Strengths

  • Multi-hour autonomous coding sessions without losing context or drifting
  • Refuses politely and specifically rather than vaguely
  • Tool-use planning paragraphs read like a research engineer's notebook

Weaknesses

  • Slower than Sonnet 4.6 on simple lookups
  • Output token cost punitive for high-volume generation
  • Extended thinking inflates billed-output 3-5×

Authentication markers

The fingerprints by which Claude Opus 4.7 can be identified from its output alone.

TellMeaning
Phrases 'I'll note that…' before tool calls.Opus 4.x lineage. Other models call tools without commentary.
Refuses with a specific alternative ('I can do X but not Y because Z') rather than 'I cannot help with that'.Constitutional-AI training surfacing.
Will say 'measure twice, cut once' or 'check with the user before proceeding' verbatim in the Claude-Code harness.Anthropic system-prompt artefact.

Notable works

  • Powering Claude Code's long-horizon refactor loops
  • Default backbone for serious agent harnesses that need 1M-token context

Market position

$15-$75 per million tokens, May 2026

Partner offer

Anthropic's Claude family is the model lineage most operators end up on for serious agent work. The free tier remains useful.

Try Claude →

Affiliate link — see disclosure.

Primary sources

  1. [1] Anthropic: Models overview
  2. [2] Anthropic: Pricing

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