Review this fictional payment-webhook policy: every failed POST is retried three times, no idempotency key is stored, and the balance is debited before the response is sent. Identify duplicate-charge risks, propose minimal changes and three acceptance tests. Use only these facts; do not assume access to code, tools or production systems.
Claude Opus 5 API: Pricing, Playground and Examples
Explore Claude Opus 5 API pricing and request formats for project planning, technical research and complex code review, with usage and reasoning guidance.
Claude Opus 5 API pricing and billing
Official price
- Input
- $5.0000 /M
- Output
- $25.0000 /M
- Cache input
- $0.5000 /M
- Cache write (5m)
- $6.2500 /M
- Cache write (1h)
- $10.0000 /M
API Hop price Save 45%
- Input
- $2.7500 /M
- Output
- $13.7500 /M
- Cache input
- $0.2750 /M
- Cache write (5m)
- $3.4375 /M
- Cache write (1h)
- $5.5000 /M
Reference price - not independently verified. Check the publisher's current rates, billing units and applicable terms before comparing costs.
Claude Opus 5 online chat tool
Model settings
It includes completed, reusable turns from this conversation in your next request, so you can ask follow-up questions without repeating the context.
What happens when it is off?Only your new message and any system prompt are sent. Existing messages stay visible; turning memory back on includes eligible earlier turns again.
Is this long-term memory?No. This is conversation context, not memory across separate conversations. Failed, stopped, truncated, or non-reusable replies are excluded. More history can use more input tokens and increase cost.
Advanced parameters
Conversation

How can I help you today?
No response data yet Claude Opus 5 prompt examples
These are evaluation prompts for Claude Opus 5, not recorded model outputs. They analyze only supplied text; they do not execute code, inspect production systems or prove long-context performance. Check quoted evidence and acceptance criteria, then review response metadata and usage before production use.
Analyze this synthetic trace: [L1] 10:00:00 request A accepted; [L2] 10:00:01 worker started A; [L3] 10:00:31 client timeout; [L4] 10:00:33 worker completed A; [L5] 10:00:35 client submitted A again. Separate observations from hypotheses, cite line IDs, list missing evidence and propose two checks. Do not claim to have inspected a real system or executed a fix.
A fictional two-person team runs 2,000 reports daily. Completion within 30 minutes is acceptable. It has a database but no queue service; jobs must recover after restart and avoid duplicate delivery. Compare a database-backed batch with a dedicated queue. Give a decision table, a conditional recommendation, three unknowns and one condition that reverses your choice. Do not invent benchmarks, costs or tested guarantees.
What is Claude Opus 5?
Claude Opus 5 model focus and core capabilities
Claude Opus 5 is an Anthropic model for demanding software engineering, knowledge work, and multi-step problem-solving. Its focus on proactive collaboration and checking its own work makes it a candidate for investigations that need more than a quick draft. It is a distinct model from Opus 5.5; a newer family overview does not describe this version.
Claude Opus 5 online tools and API on API Hop
API Hop provides a text Playground, unified Chat Completions, and Claude Messages for Claude Opus 5. Test a bounded task online before integrating it into an application. Native image understanding and tool use require appropriate interfaces and execution environments; this chat tool does not upload files, browse the web, or operate your systems.
Claude Opus 5 capabilities and domain strengths
Opus 5 is relevant when an answer must connect requirements, evidence, and next steps. Give it an explicit scope and a definition of success so proactive suggestions remain useful rather than becoming unapproved work.
Root-cause analysis and substantial software changes
Use Claude Opus 5 to examine a failing behavior alongside related code, caller expectations, and logs. Ask it to separate the visible symptom from a possible underlying cause, then propose the smallest change and the test that would confirm it.
For repository-wide work, supply dependency boundaries and behavior that must remain unchanged. The Playground only returns text: file access, compilation, test execution, and review of the final diff belong in your development environment.
Professional material and evidence-preserving synthesis
A useful document analysis preserves who said what, which statements conflict, and which decisions remain open. Give each source a stable label and ask for a decision record instead of immediately requesting a smooth combined narrative.
Opus 5 can be evaluated on technical proposals, research notes, and project briefs using this approach. Keep quotations and numerical claims traceable to supplied material; a plausible explanation does not resolve missing evidence or confer professional authority.
Visual understanding and interactive implementation drafts
Opus 5 supports native text and image inputs with text output. This creates opportunities for interface interpretation and document analysis when the selected integration actually accepts image content.
Here, describe layouts, states, and data in text, then request a component plan or code draft. A pasted image URL does not prove that the image was inspected. Validate generated interfaces in a browser, including mobile layout, asset loading, and keyboard behavior.
Proactive planning with explicit approval boundaries
For a complex task, ask the model to identify missing information, rank dependencies, and suggest an observable next step. In a pilot brief, available staff, approved sources, excluded features, and stop conditions are more useful than an unconstrained ambition.
Keep proposed actions separate from authorized actions. Do not let a plan silently create a budget, deadline, policy, or commitment; ask it to mark estimates and unresolved choices so a responsible person can approve them.
How to evaluate Claude Opus 5 for your workload
Coding, knowledge work, and automation benchmarks provide task-selection signals, not a API Hop latency or success-rate guarantee. Evaluate this exact model and protocol rather than borrowing results from Opus 5.5 or another Claude version.
| Task input | Checks | Pass criteria | Metrics to record |
|---|---|---|---|
| A proposal review with conflicting project notes and a bounded deliverable | Check source attribution, commitments, missing decisions, and each handoff | Required constraints are preserved; claims are supported and unperformed actions are not reported as complete | Unsupported claims, lost attribution, rework, duration, token usage |
Evaluate engineering outcomes, not persuasive explanations
Build a small set of known defects with relevant files and expected behavior. Score whether the proposed change addresses the root cause, preserves working cases, and supplies useful regression coverage rather than counting the length of the explanation.
Tool-enabled coding evaluations include a harness that can inspect files and run checks. A single text answer has no equivalent execution feedback; require actual test results before accepting a claimed repair.
Measure useful knowledge-work completion
Test a proposal review, conflicting project notes, and a bounded project brief. Count unsupported claims, lost source attribution, invented commitments, and missing decisions. These measures reveal whether an attractive draft is usable in your workflow.
For multi-step work, check every handoff as well as the final document. A good plan is not proof of successful retrieval, analysis, or delivery; the application must provide and verify those operations.
Compare quality, duration, and usage together
Keep inputs, acceptance criteria, and output requirements consistent. Record useful-answer quality, rework, time to first text, total duration, and actual token usage across several samples before choosing an operating configuration.
Long context, retained history, and a larger output allowance can increase usage. Where thinking is produced, allow space for the final text and inspect the completion state; faster arrival of a partial response is not the same as faster completion of a correct task.
Claude Opus 5 compared with Claude and GPT models
Compare Opus 5 with relevant catalog choices on the same work. The table describes evaluation questions, not unverified rankings or a promise that one model wins every task.
| Task | Claude Opus 5 | Catalog alternatives | How to validate |
|---|---|---|---|
| Difficult code investigation | Root-cause review candidate | Claude Opus 4.8, GPT-5.6 Sol | Run the regression and check side effects |
| Professional source synthesis | Evidence-preserving analysis candidate | Claude Fable 5, GPT-5.6 Sol | Check attribution and unresolved claims |
| Bounded workflow planning | Proactive planning candidate | Claude Sonnet 5, Claude Fable 5 | Check scope, dependencies, and approvals |
| Routine text processing | Measure whether added depth is useful | Claude Sonnet 5, Claude Opus 4.8 | Compare quality, usage, and total duration |
When to prioritize testing Claude Opus 5
Include Opus 5 in evaluations where difficult debugging, competing requirements, or ambiguous professional material make shallow answers costly. Provide enough evidence to judge the proposed reasoning and require it to identify what would change its recommendation.
For a short extraction or rewrite, additional analysis may not improve the outcome. Compare against Sonnet 5 or your existing Opus 4.8 workflow using the same rubric before changing models or increasing the budget.
Choose models by task on API Hop
Compare Claude Fable 5 and GPT-5.6 Sol for demanding analysis, and use the Claude version pages to evaluate migration-sensitive tasks. Shared Chat Completions can simplify request reuse, while Claude Messages retains a different native response contract.
Use current account prices and your measured results to assign workflow steps. Model names do not establish latency, cost, or reliability, and a successful minimal request does not verify every optional parameter or tool configuration.
Why use Claude Opus 5 through API Hop?
Usage-based billing and model cost optimization
Charges follow current API Hop rates and actual usage. Top up on demand.
Unified AI models and data APIs, with multi-model access in one place
One API key connects multiple AI models and data services, reducing integration costs and letting you switch with one click. Business applications need both AI and data.
Call logs and application access controls, with clarity on every call
Every API call is recorded in your dashboard. Create separate API keys for different applications.
Evaluate outputs against your task
Use the documented model ID and supported parameters through API Hop. Evaluate outputs against your own acceptance criteria, then inspect usage records and response metadata before production use. A model name or example does not guarantee each result.
How to use Claude Opus 5 on API Hop
After creating an API key in the console, follow the documentation to get started with Claude Opus 5.
Prepare your account and test online
Sign in, confirm your balance, and create an API key.
Try it in the Playground
Explore the model's capabilities in the Playground to find the best way to use it.
Integrate Claude Opus 5 into your business
Follow our developer documentation to integrate Claude Opus 5 into your business.
Future model upgrades
To switch to a newer model, first confirm that its exact ID is returned by the model catalog for your API key. If it supports the same endpoint and request fields, update the model ID, then test response formats, streaming, output limits and billing before sending production traffic. For asynchronous image or video tasks, also verify job submission, status polling and result retrieval.
Claude Opus 5 API FAQ
Is Claude Opus 5 the same API model as Opus 4.8?
No. The API model name for Claude Opus 5 is claude-opus-5; the API model name for Claude Opus 4.8 is claude-opus-4-8. They are different models, so do not mix up their model parameters.
Why is thinking empty or the answer incomplete?
Native Opus 5 uses adaptive thinking by default and can omit thinking text. Empty thinking alone is not a failure. Disabling thinking requires the configuration supported by this model. For an incomplete answer, check the completion state and output allowance, leaving enough room for thinking and final text.
How should I troubleshoot authentication, balance, or access errors?
Follow the API error documentation to diagnose the issue.
Can I use OpenAI Responses for Claude Opus 5?
OpenAI Responses is not supported. Claude has its own Claude Messages format; see the documentation for details.
Can I force a tool call or edit a native Messages conversation?
Native Opus 5 supports forced tool_choice types any or tool with adaptive thinking. Follow the documentation for the interface you use. Take care when replaying preserved thinking after editing earlier messages. Keep native assistant content blocks and their signatures intact during tool continuations.
Is conversation memory permanent?
No. The API does not automatically retain conversation context for subsequent requests. Manage the history yourself and include the required context in each request. Long-term memory must be implemented by your application.
Related text APIs
Claude Opus 5 API examples and supported parameters
Claude Opus 5 API quickstart
claude-opus-5model is required; these examples use the current page model ID. Check model access for your API key with GET /v1/models.
Chat CompletionsPOST /v1/chat-completions
curl -X POST "https://api.apihop.ai/v1/chat-completions" \
-H "Authorization: Bearer <API_KEY>" \
-H "Content-Type: application/json" \
-d '{"model":"claude-opus-5","messages":[{"role":"user","content":"Hello, introduce yourself in one sentence."}],"stream":false}'MessagesPOST /anthropic/v1/messages
Messages requires max_tokens. The allowance in this example is editable, not an upstream default or a model limit. Thinking may consume it before any answer text; adjust it for your task and check output costs.
curl -X POST "https://api.apihop.ai/anthropic/v1/messages" \
-H "Authorization: Bearer <API_KEY>" \
-H "Content-Type: application/json" \
-H 'anthropic-version: 2023-06-01' \
-d '{"model":"claude-opus-5","max_tokens":4096,"messages":[{"role":"user","content":"Hello, introduce yourself in one sentence."}],"stream":false}'Family and protocol reference
Claude Messages
Full API documentationNative Claude Messages-compatible API. This endpoint uses Anthropic Messages request and response shapes, including tool calls and Anthropic SSE events.
https://api.apihop.ai/anthropic/v1/messages