Source: https://ailoot.ai/models/en/claude-opus-4-20250514-thinking/
Canonical: https://ailoot.ai/models/en/claude-opus-4-20250514-thinking/
Language: en

# claude-opus-4-20250514-thinking

[Markdown](https://ailoot.ai/models/en/claude-opus-4-20250514-thinking/index.md) · [JSON](https://ailoot.ai/models/en/claude-opus-4-20250514-thinking/facts.json)

## [claude-opus-4-20250514-thinking](https://ailoot.ai/models/en/claude-opus-4-20250514-thinking/)

Claude Opus 4 Thinking uses the original Opus 4’s extended-thinking mode for complex software changes, sustained agent workflows and research. It can reason between supported tool steps and connect evidence across a demanding task before producing a text result.

- [**Ailoot Ultra · OpenAI Chat** `POST /v1/chat/completions` `claude-opus-4-20250514-thinking`](https://ailoot.ai/models/en/claude-opus-4-20250514-thinking/#method-0)

About the model

This description covers the model’s capabilities. Available in Ailoot inputs, outputs and options are listed for the selected method below.

Claude Opus 4 Thinking applies extended reasoning to the original Claude Opus 4 model. Anthropic positions this generation for difficult programming work, research, writing and tasks that require maintaining direction across many steps. The Thinking designation concerns how the model approaches a response; it does not turn the original Opus 4 into a later Opus edition.

#### Reasoning across a demanding task

Claude Opus 4 combines a standard response mode with an extended-thinking mode. In extended thinking, it can spend more time examining a problem before answering. The manufacturer describes sustained work on complex tasks as a central strength, especially when a task requires connecting a sequence of findings rather than solving isolated prompts.

For a research question, provide the materials to compare, the decision they should support and the conditions that matter. Ask for an evidence-based synthesis that separates findings, assumptions and open questions. For a writing task, include the audience, source material, required structure and the claims the result must explain. These are practical applications of the model’s documented research and writing capabilities, rather than promises of a particular outcome.

#### Changes across a codebase

Anthropic emphasises complex code understanding, editing, debugging and changes spanning multiple files. Give the model the relevant modules, interface contracts, expected behaviour and existing tests or error output. Define the scope of the requested change and ask it to explain the dependencies that make the proposed edits necessary.

A useful engineering result connects three things: the cause of the problem, a consistent implementation and a way to check the resulting behaviour. For a refactor, state which public interfaces and observable behaviours must remain stable. For a feature, describe the user flow and its failure cases. This makes the model’s sustained reasoning useful to the project rather than merely producing a longer answer.

#### Tools, parallel work and continuity

The original Claude 4 generation adds reasoning between tool calls in Anthropic’s documented extended-thinking workflow. It can examine a tool result, reconsider its approach and choose a subsequent action. The manufacturer also describes parallel tool use and improved continuity when an application supplies local files that the model can read and update.

An agent using these capabilities needs its application to provide the tools, execute requested actions and return their results. Memory files likewise belong to the application environment; they are not an unlimited store carried automatically between unrelated conversations. When designing a workflow, return relevant observations to the model and keep the task’s goal and acceptance criteria available.

#### Visual analysis and text output

Claude Opus 4 also supports visual analysis. Screenshots, charts and diagrams can supply evidence alongside text, while the model’s answer remains textual. Use clearly readable images and identify the relationships you want explained. Include source values when the task depends on exact counts or measurements, since visual interpretation can be approximate.

For an Ailoot API task, specify the final artifact you need: a multi-file change proposal, a technical investigation, a research synthesis or a carefully structured document. Add the evidence and constraints that let the model choose an approach. The manufacturer’s extended-thinking summaries provide an explanation alongside the result, but a summary is not a verbatim record of all reasoning. Inspect the delivered code or analysis against the task’s requirements, including any assumptions that still need evidence.

Practical task

### Plan a coordinated order refactor

Technical example in English

```
Plan a coordinated order refactor

Review this proposed refactor. Module A emits {order_id, total_cents}; module B stores those fields; module C displays total_cents / 100. A developer proposes renaming only A to amount_cents. Identify affected contracts and propose a coordinated migration that preserves existing consumers, with checks for old and new records.
```

#### Expected result

```
A dependency map in text, a staged migration proposal and compatibility checks for each consumer.
```

#### Check the result

```
Confirm the proposal covers B and C and does not silently reinterpret cents as whole currency units.
```

**Ailoot Ultra · OpenAI Chat** `POST /v1/chat/completions` `claude-opus-4-20250514-thinking`

[`claude-opus-4-20250514-thinking`](https://ailoot.ai/models/en/#m=claude-opus-4-20250514-thinking&route=Ultra&caller=claude-opus-4-20250514-thinking&fmt=chat)

Anthropic /`claude-opus-4-20250514-thinking`

### Overview

Claude Opus 4 Thinking uses the original Opus 4’s extended-thinking mode for complex software changes, sustained agent workflows and research. It can reason between supported tool steps and connect evidence across a demanding task before producing a text result.

Accepted inputs

Text

Results

Text

### Available in Ailoot · inputs & methods

**Ailoot Ultra · OpenAI Chat** `POST /v1/chat/completions`

Input types

`text`

Output types

`text`

Output format

json or SSE

| Field | Type | Requirement | Values & limits | Default |
| --- | --- | --- | --- | --- |
| Field`model` | Type`string` | RequirementRequired | Values & limits claude-opus-4-20250514-thinking | Default— |
| Field`messages` | Type`message[]` | RequirementRequired | Values & limits Minimum items: 1 | Default— |
| Field`messages[].role` | Type`string` | RequirementRequired | Values & limits Examples: system, user, assistant, tool, function Conditions: These roles are explicitly represented by Source compatibility types; the exact model role set remains model-specific. Model-specific | Default— |
| Field`messages[].content` | Type`string\|content_part[]\|null` | RequirementOptional | Values & limits | Default— |
| Field`messages[].tool_calls` | Type`tool_call[]` | RequirementOptional | Values & limits | Default— |
| Field`messages[].tool_call_id` | Type`string` | RequirementOptional | Values & limits Applies when: role=tool; use actual returned ID | Default— |
| Field`messages[].name` | Type`string` | RequirementOptional | Values & limits | Default— |
| Field`messages[].reasoning_content` | Type`string` | RequirementOptional | Values & limits Applies when: Round-trip actual returned reasoning where this model uses it | Default— |
| Field`messages[].reasoning_details` | Type`object\|array` | RequirementOptional | Values & limits Model-specific | Default— |
| Field`max_tokens` | Type`integer` | RequirementOptional | Values & limits Minimum: 1 Model-specific | Default— |
| Field`max_completion_tokens` | Type`integer` | RequirementOptional | Values & limits Minimum: 1 Model-specific | Default— |
| Field`stream` | Type`boolean` | RequirementOptional | Values & limits | Defaultfalse |
| Field`stream_options.include_usage` | Type`boolean` | RequirementOptional | Values & limits Model-specific | Default— |
| Field`temperature` | Type`number` | RequirementOptional | Values & limits Model-specific | Default— |
| Field`top_p` | Type`number` | RequirementOptional | Values & limits Model-specific | Default— |
| Field`stop` | Type`string\|string[]` | RequirementOptional | Values & limits Model-specific | Default— |
| Field`tools` | Type`function_tool[]` | RequirementOptional | Values & limits Model-specific | Default— |
| Field`tools[].type` | Type`string` | RequirementOptional | Values & limits function Model-specific | Default— |
| Field`tools[].function.name` | Type`string` | RequirementRequired | Values & limits Applies when: function tool supplied | Default— |
| Field`tools[].function.description` | Type`string` | RequirementOptional | Values & limits | Default— |
| Field`tools[].function.parameters` | Type`JSON_schema` | RequirementOptional | Values & limits | Default— |
| Field`tool_choice` | Type`string\|object` | RequirementOptional | Values & limits Model-specific | Default— |
| Field`parallel_tool_calls` | Type`boolean` | RequirementOptional | Values & limits Model-specific | Default— |
| Field`response_format` | Type`object` | RequirementOptional | Values & limits Model-specific | Default— |
| Field`reasoning_effort` | Type`string` | RequirementOptional | Values & limits Model-specific | Default— |
| Field`reasoning` | Type`object` | RequirementOptional | Values & limits Model-specific | Default— |
| Field`service_tier` | Type`string` | RequirementOptional | Values & limits Model-specific | Default— |
| Field`instructions` | Type`string` | RequirementOptional | Values & limits Compatibility field | Default— |
| Field`functions` | Type`function[]` | RequirementOptional | Values & limits Model-specific | Default— |
| Field`function_call` | Type`string\|object` | RequirementOptional | Values & limits Model-specific | Default— |
| Field`prompt_cache_options` | Type`object` | RequirementOptional | Values & limits Model-specific | Default— |
| Field`modalities` | Type`string[]` | RequirementOptional | Values & limits text | Default— |
| Field`provider` | Type`object` | RequirementOptional | Values & limits Conditions: provider.options is rejected on this Ultra text route | Default— |
| Field`cache_control.ttl` | Type`string` | RequirementOptional | Values & limits Conditions: 1h is rejected in actual prompt-cache locations | Default— |

Input material combinations

**Text** · UTF8 text

`messages[].content`

Method parameters and lifecycle

| Parameter | Contract |
| --- | --- |
| Parameter`content_type` | Contractapplication/json |
| Parameter`required` | Contractmodel, messages |
| Parameter`material_types` | Contracttext |
| Parameter`messages` | Contractmessage array with role/content shape |
| Parameter`file_material` | Contractactual UTF-8 document inserted as literal text; no file ID inferred |
| Parameter`optional_controls` | Contractstream, temperature, top\_p, stop, max\_tokens, max\_completion\_tokens, reasoning, response\_format, tools, tool\_choice |
| Parameter`control_scope` | Contractmodel-specific; user function tools differ from hosted tools |
| Parameter`output_modalities` | Contracttext |
| Parameter`hosted_operations` | Contractfalse |
| Parameter`multimodal_input_binding` | Contractnull |

Lifecycle: `synchronous_or_streamed`

Send exact model ID with messages.

Context length is not an output cap.

A text file may supply literal text; image/audio/file-object inputs need exact binding.

### Pricing

Tariff references do not add request options. Supported parameters are listed for the selected method.

Fast mode

Not specified When fast mode is selected

Flex mode

Not specified When flex mode is selected

Maximum reasoning effort

Not specified When maximum reasoning effort uses the default adjustment

#### Ailoot rates

#### Prices by configuration

| Configuration | Rate schedule | Charge |
| --- | --- | --- |
| ConfigurationBase token rates | Rate scheduleBase rate | Charge Input · Input tokens **$0.03** / 1K tokens Output · Output tokens **$0.15** / 1K tokens Input · Cache read **$0.0006** / 1K tokens Input · Cache write **$0.0075** / 1K tokens Input · Cache write, 1 hour **—** / 1K tokens |

Ailoot reserves an estimated amount before a request. After the result, it settles the final charge from measured usage. Streaming settlement uses the final usage record. [How reservation and settlement work →](https://ailoot.ai/docs/en/billing/reserve/)

### Example requests

#### Ailoot Ultra · OpenAI Chat

curlPython SDKPython stream

```bash
set -eu
: "${AILOOT_API_KEY:?Set your Ailoot API key}"
python3 - <<'PY_REQUEST'
import json,os
from pathlib import Path
p=json.loads('{"model": "claude-opus-4-20250514-thinking", "messages": [{"role": "user", "content": "Explain the difference between an observation and a hypothesis in three sentences."}]}')

Path("request.json").write_text(json.dumps(p,ensure_ascii=False))
PY_REQUEST
curl --fail-with-body --silent --show-error https://api.ailoot.ai/v1/chat/completions \
  -H "Authorization: Bearer $AILOOT_API_KEY" -H 'Content-Type: application/json' \
  --data-binary @request.json -D response-headers.txt -o result.json
python3 - <<'PY_RESULT'
import json
from pathlib import Path
r=json.loads(Path("result.json").read_text())
for x in r.get("choices",[]):
    if x.get("message",{}).get("content"): print(x["message"]["content"])
PY_RESULT
```

```python
from openai import OpenAI
import os

if not os.environ.get("AILOOT_API_KEY", "").strip(): raise SystemExit("Set AILOOT_API_KEY before making a request")
client=OpenAI(base_url="https://api.ailoot.ai/v1",api_key=os.environ["AILOOT_API_KEY"],max_retries=0)
result=client.chat.completions.create(model='claude-opus-4-20250514-thinking',messages=[{"role":"user","content":"Explain observations and hypotheses in three sentences."}])
import base64, json
from pathlib import Path

def save_result(data, stem="result"):
    # Keep every field, including usage, IDs, reasoning and tool requests.
    Path(stem + ".json").write_text(json.dumps(data, ensure_ascii=False, indent=2), encoding="utf-8")
    print(json.dumps(data, ensure_ascii=False, indent=2))
    def save_blob(encoded, suffix, label):
        raw = base64.b64decode(encoded, altchars=b"-_", validate=True)
        ext = "png" if raw.startswith(b"\x89PNG\r\n\x1a\n") else "jpg" if raw.startswith(b"\xff\xd8") else "webp" if raw[:4] == b"RIFF" and raw[8:12] == b"WEBP" else suffix
        file = Path(stem + "-" + label + "." + ext)
        file.write_bytes(raw)
        print("Saved", file)
    for index, block in enumerate(data.get("content") or []):
        print("Content", index, json.dumps(block, ensure_ascii=False))
    for choice in data.get("choices") or []:
        print("Choice", choice.get("index"), json.dumps(choice.get("message", choice.get("delta", {})), ensure_ascii=False))
    for index, item in enumerate(data.get("output") or []):
        print("Output", index, json.dumps(item, ensure_ascii=False))
        if item.get("type") == "image_generation_call" and item.get("result"):
            save_blob(item["result"], item.get("output_format") or "bin", "output-" + str(index))
    for ci, candidate in enumerate(data.get("candidates") or []):
        for pi, part in enumerate((candidate.get("content") or {}).get("parts") or []):
            print("Candidate/part", ci, pi, json.dumps(part, ensure_ascii=False))
            blob = part.get("inlineData") or part.get("inline_data")
            if blob and blob.get("data"):
                mime = blob.get("mimeType") or blob.get("mime_type")
                suffix = {"image/png":"png", "image/jpeg":"jpg", "image/webp":"webp", "audio/wav":"wav", "audio/mpeg":"mp3", "video/mp4":"mp4"}.get(mime, "bin")
                save_blob(blob["data"], suffix, "candidate-" + str(ci) + "-part-" + str(pi))

save_result(result.to_dict(mode="json"))
```

```python
from openai import OpenAI
import os
from pathlib import Path

if not os.environ.get("AILOOT_API_KEY", "").strip(): raise SystemExit("Set AILOOT_API_KEY before making a request")
client=OpenAI(base_url="https://api.ailoot.ai/v1",api_key=os.environ["AILOOT_API_KEY"],max_retries=0)
import base64, json
from pathlib import Path

def save_result(data, stem="result"):
    # Keep every field, including usage, IDs, reasoning and tool requests.
    Path(stem + ".json").write_text(json.dumps(data, ensure_ascii=False, indent=2), encoding="utf-8")
    print(json.dumps(data, ensure_ascii=False, indent=2))
    def save_blob(encoded, suffix, label):
        raw = base64.b64decode(encoded, altchars=b"-_", validate=True)
        ext = "png" if raw.startswith(b"\x89PNG\r\n\x1a\n") else "jpg" if raw.startswith(b"\xff\xd8") else "webp" if raw[:4] == b"RIFF" and raw[8:12] == b"WEBP" else suffix
        file = Path(stem + "-" + label + "." + ext)
        file.write_bytes(raw)
        print("Saved", file)
    for index, block in enumerate(data.get("content") or []):
        print("Content", index, json.dumps(block, ensure_ascii=False))
    for choice in data.get("choices") or []:
        print("Choice", choice.get("index"), json.dumps(choice.get("message", choice.get("delta", {})), ensure_ascii=False))
    for index, item in enumerate(data.get("output") or []):
        print("Output", index, json.dumps(item, ensure_ascii=False))
        if item.get("type") == "image_generation_call" and item.get("result"):
            save_blob(item["result"], item.get("output_format") or "bin", "output-" + str(index))
    for ci, candidate in enumerate(data.get("candidates") or []):
        for pi, part in enumerate((candidate.get("content") or {}).get("parts") or []):
            print("Candidate/part", ci, pi, json.dumps(part, ensure_ascii=False))
            blob = part.get("inlineData") or part.get("inline_data")
            if blob and blob.get("data"):
                mime = blob.get("mimeType") or blob.get("mime_type")
                suffix = {"image/png":"png", "image/jpeg":"jpg", "image/webp":"webp", "audio/wav":"wav", "audio/mpeg":"mp3", "video/mp4":"mp4"}.get(mime, "bin")
                save_blob(blob["data"], suffix, "candidate-" + str(ci) + "-part-" + str(pi))

with client.chat.completions.stream(model='claude-opus-4-20250514-thinking',messages=[{"role":"user","content":"Explain observations and hypotheses in three sentences."}]) as stream:
    with Path("stream-events.jsonl").open("w",encoding="utf-8") as log:
        for event in stream:
            payload=event.to_dict(mode="json")
            log.write(json.dumps(payload,ensure_ascii=False)+"\n"); log.flush()
            print(json.dumps(payload,ensure_ascii=False))
    final=stream.get_final_completion()
    save_result(final.to_dict(mode="json"),"stream-result")
```

### Receive and save results

#### Ailoot Ultra · OpenAI Chat

json or SSE

##### Keep all completed results

Keep every complete returned response, file and content part.

Keep every choice and its content/tool calls/reasoning. In SSE assemble deltas by choice/tool index, retain the final finish reason and usage.

##### If the original response needs checking

Keep request/response IDs and headers. No generic text job retrieval URL is supplied.

Response fields

| Field | Type |
| --- | --- |
| Field`choices[].index` | Typeinteger |
| Field`choices[].message.content` | Typestring\|null |
| Field`choices[].message.tool_calls` | Typetool\_call\[\] |
| Field`choices[].message.reasoning_content` | Typestring |
| Field`choices[].message.reasoning_details` | Typeobject\|array |
| Field`choices[].finish_reason` | Typestring\|null |
| Field`usage` | Typeobject |

Errors and next steps

| Response | Condition | Next step |
| --- | --- | --- |
| Response400 · `invalid_request_error` | ConditionInvalid required fields, material representation or parameter value | Next stepCorrect the indicated fields before a new creation request. |

### Aliases

#### Model aliases

**Ailoot Ultra** [`claude-opus-4-20250514-thinking`](https://ailoot.ai/models/en/#m=claude-opus-4-20250514-thinking&route=Ultra&caller=claude-opus-4-20250514-thinking&fmt=chat)

#### Method path aliases

Use the method paths shown above.

#### Related caller IDs

[`claude-opus-4-20250514-thinking`](https://ailoot.ai/models/en/#m=claude-opus-4-20250514-thinking&route=Ultra&caller=claude-opus-4-20250514-thinking&fmt=chat)

FAQ · claude-opus-4-20250514-thinking

What inputs and results are available?

`POST /v1/chat/completions` · `claude-opus-4-20250514-thinking`: `text` → `text`

Which fields does the request use?

`POST /v1/chat/completions` · `claude-opus-4-20250514-thinking`: `model`, `messages`, `stream`, `modalities`, `provider`

What limits apply?

`POST /v1/chat/completions` · `claude-opus-4-20250514-thinking`: `messages.min_items`: `1`

Connect Ailoot to Claude Code, OpenCode, Hermes or your own app.

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Ailoot combines established operating experience, a large client base, stable service and ongoing KPI control.





The company and its project portfolio: millions of customers; monthly sales in the billions.





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