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Claude Opus 5 Priority

Priority

Anthropic · 200K context · 32K max output. Priority routing and higher cache efficiency for coding agents; billed at the priority rate.

claude-opus-5-max
Use this model

Specifications

Model id
claude-opus-5-max
Vendor
Anthropic
Tier
Priority
Context window
200K tokens
Max output
32K tokens
Capabilities
Streaming, Tool calls, Vision, Reasoning, Structured outputs, Prompt caching
Endpoints
/v1/chat/completions, /v1/responses, /v1/messages

Pricing

USD per 1M tokens, excl. VAT. Identical for API and chat.

TokensPriority rate
Input$4.50
Output$22.50
Cached input$0.45

Call it

Both endpoint families, with this model id filled in. Set HALFBILL_API_KEY and run.

OpenAI-compatible (cURL)
curl https://api.halfbill.uk/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $HALFBILL_API_KEY" \
  -d '{
    "model": "claude-opus-5-max",
    "messages": [{"role": "user", "content": "Say hello in one line."}]
  }'

Frequently asked questions

Is this the same Claude Opus 5 Priority as Anthropic's?

Yes. Requests to "claude-opus-5-max" are served by the same model. Halfbill is an independent service and is not affiliated with Anthropic; we bill at our own prices.

What does Claude Opus 5 Priority cost on Halfbill?

$4.50 per 1M input tokens and $22.50 per 1M output tokens at the priority rate, $0.45 per 1M cached input tokens. USD, excl. VAT.

Which endpoints can I use?

The OpenAI-compatible /v1/chat/completions and /v1/responses endpoints and the Anthropic-compatible /v1/messages endpoint at https://api.halfbill.uk, with the model id "claude-opus-5-max".

How large is the context window?

200K tokens of context and up to 32K output tokens per request, as listed in the catalog.

Does it work in Claude Code and Cursor?

Yes. Set ANTHROPIC_BASE_URL=https://api.halfbill.uk and ANTHROPIC_AUTH_TOKEN to your Halfbill key for Claude Code, or override the OpenAI base URL to https://api.halfbill.uk/v1 in Cursor and add "claude-opus-5-max" as a custom model.

What does Priority mean?

Priority routing and higher cache efficiency for coding agents; billed at the priority rate. The standard-tier variant of this model is available at half the list price.

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Context
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Max output
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  • Reasoning
  • Structured outputs
  • Prompt caching
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$7.50/ 1M in
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Vendor
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Context
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Max output
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  • Tool calls
  • Vision
  • Reasoning
  • Structured outputs
  • Prompt caching
Halfbill price
$3.75/ 1M in
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$18.75/ 1M out
list $37.50
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Halfbill is an independent service and is not affiliated with, endorsed by, or sponsored by OpenAI or Anthropic. Model names are trademarks of their respective owners.