# Claude Opus 5 — API, capabilities & pricing | Y-API

> Claude Opus 5 is positioned by OpenRouter as Anthropic’s model for demanding reasoning, software engineering and extended agent work. The reference entry lists text, image and file input with text output.

This is the markdown representation of https://y-api.bestvirtualgoods.com/models/anthropic/claude-opus-5. Generated by `scripts/generate-seo-assets.mjs` from the same copy the page renders — do not edit by hand.

Model ID: `anthropic/claude-opus-5`

Sources reviewed: 2026-10-04. Y-API catalog snapshot: 2026-10-04.

## Choosing this model

Selection advice by Y-API. The checks below are suggested evaluations, not published test results.

### Where to start

Consider it as a second-pass reviewer for a consequential architecture change or difficult bug. Give it the original requirements, a proposed diff and concrete failure scenarios to challenge.

### What to watch for

A premium model can still miss a defect or invent an explanation. Validate findings against code and tests. File inputs listed by OpenRouter do not prove that Y-API exposes Anthropic’s native document handling.

## Model specifications

These are OpenRouter model-level specifications, not a Y-API compatibility test. A particular route may accept fewer input formats, parameters or tokens. Verify the features you need with a small request; a successful text response does not validate vision or tool calling.

| Field | Value |
| --- | --- |
| Context window | 1,000,000 tokens |
| Input | Text, Image, File |
| Output | Text |
| Listed on OpenRouter | 2026-07-24 |
| Parameters listed by OpenRouter | `include_reasoning`, `max_completion_tokens`, `max_tokens`, `reasoning`, `reasoning_effort`, `response_format`, `stop`, `structured_outputs`, `temperature`, `tool_choice`, `tools`, `verbosity` |

## Estimate your cost

| Price basis | Input / 1M tokens | Output / 1M tokens |
| --- | --- | --- |
| Account credit | $5.00 | $25.00 |
| Cash equivalent | $0.50 | $2.50 |

$1 paid adds $10 of credit. Cash equivalent = credit consumed ÷ 10; this is not the model publisher’s list price.

Input tokens / request: 1000. Output tokens / request: 500. Number of requests: 1000.

Estimated credit consumed: $17.50. Estimated cash equivalent: $1.75.

Illustrative token budget, not measured usage or a quote. Includes input and output; excludes separate media charges, cache discounts and retries. Include billed reasoning tokens in your output budget where applicable. Actual billing follows usage returned by the service.

### Same token budget, different models

| Model | Estimated credit consumed | Estimated cash equivalent |
| --- | --- | --- |
| [Claude Opus 5](https://y-api.bestvirtualgoods.com/models/anthropic/claude-opus-5) | $17.50 | $1.75 |
| [Claude Sonnet 5](https://y-api.bestvirtualgoods.com/models/anthropic/claude-sonnet-5) | $7.00 | $0.70 |
| [GPT-5.6 Sol](https://y-api.bestvirtualgoods.com/models/openai/gpt-5.6-sol) | $20.00 | $2.00 |

## Use the API

These minimal, text-only requests use the exact Y-API model ID. They do not demonstrate image, audio, video, file or tool support. The output limit also needs room for reasoning; an empty answer with finish_reason=length can mean the budget was exhausted.

Set the TOKEN environment variable to a key from your console. Run this on your server or locally; never expose a key in browser code or a public repository.

### A task to try

Review this cache policy: private account responses use Cache-Control: public, max-age=300. Explain the risk and propose headers and regression tests.

```bash
curl --fail-with-body --silent --show-error --max-time 120 \
  'https://api.y-api.bestvirtualgoods.com/v1/chat/completions' \
  -H "Authorization: Bearer ${TOKEN:?Set TOKEN first}" \
  -H 'Content-Type: application/json' \
  --data-binary @- <<'JSON'
{
  "model": "anthropic/claude-opus-5",
  "messages": [
    {
      "role": "user",
      "content": "Review this cache policy: private account responses use Cache-Control: public, max-age=300. Explain the risk and propose headers and regression tests."
    }
  ],
  "max_tokens": 4096
}
JSON
```

```python
import json
import os
import sys
import urllib.error
import urllib.request

payload = {
  "model": "anthropic/claude-opus-5",
  "messages": [
    {
      "role": "user",
      "content": "Review this cache policy: private account responses use Cache-Control: public, max-age=300. Explain the risk and propose headers and regression tests."
    }
  ],
  "max_tokens": 4096
}

request = urllib.request.Request(
    "https://api.y-api.bestvirtualgoods.com/v1/chat/completions",
    data=json.dumps(payload).encode("utf-8"),
    headers={
        "Authorization": "Bearer " + os.environ["TOKEN"],
        "Content-Type": "application/json",
    },
    method="POST",
)
try:
    with urllib.request.urlopen(request, timeout=120) as response:
        result = json.load(response)
    print(json.dumps(result, ensure_ascii=False, indent=2))
except urllib.error.HTTPError as error:
    print(error.read().decode("utf-8"), file=sys.stderr)
    raise SystemExit(1)
```

### How to evaluate the result

The review should identify cross-user data leakage, propose an appropriate private or no-store policy and test authenticated responses. Avoid accepting generic security advice without a failure mechanism.

## Before you choose

### Does Opus justify its higher cost than Sonnet?

Only a task-level comparison can establish that. Compare defects caught, accepted fixes, retries and total billed tokens. Reserve a more expensive reviewer for cases where it measurably changes the outcome.

## Sources & scope

Technical facts come from the cited model page and, where available, its linked publisher card. A card describes that checkpoint; it is not proof of the weights a gateway serves. Prices come only from the Y-API catalog. We do not claim measured latency, uptime or benchmark scores for this endpoint.

- [OpenRouter model page & specifications](https://openrouter.ai/anthropic/claude-opus-5)
- [Y-API catalog & prices (JSON)](https://y-api.bestvirtualgoods.com/models.json)

## Models to compare

Compare these alternatives on the same inputs. Their descriptions explain different roles; a lower price does not establish equivalent quality.

### [Claude Sonnet 5](https://y-api.bestvirtualgoods.com/models/anthropic/claude-sonnet-5)

Claude Sonnet 5 is Anthropic’s Sonnet-class model for coding and professional work. The reviewed reference describes adaptive thinking and an updated tokenizer, so migration involves more than changing a display name.

### [GPT-5.6 Sol](https://y-api.bestvirtualgoods.com/models/openai/gpt-5.6-sol)

GPT-5.6 Sol is the flagship entry of the GPT-5.6 family in OpenRouter’s catalog. Its stated focus is complex reasoning, command-line coding and multi-step problem solving, with text, image and file inputs listed in the reference.

## Links

- HTML version of this page: https://y-api.bestvirtualgoods.com/models/anthropic/claude-opus-5
- Site index for agents: https://y-api.bestvirtualgoods.com/llms.txt
- Full reference (single file): https://y-api.bestvirtualgoods.com/llms-full.txt
- OpenAPI 3.1 spec: https://y-api.bestvirtualgoods.com/openapi.json
- Model catalog (JSON, no key needed): https://y-api.bestvirtualgoods.com/models.json
- API base URL: `https://api.y-api.bestvirtualgoods.com/v1`
- Contact: support@bestvirtualgoods.com
- Model catalog: https://y-api.bestvirtualgoods.com/models
- Integration guide: https://y-api.bestvirtualgoods.com/docs