overview changedagents-and-tools/tool-use/overview
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Lines+17added
Lines−18removed
From line
16
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First seen
14 Aug 2026
this site's first read of the page
Recorded edits23to this page, all time
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from line 16, old and new numbered
/
from line 16
1616 -H "content-type: application/json" \
1717 -d '{
1818 "model": "claude-opus-5-5",
19 "max_tokens": 1024,
19 "max_tokens": 4096,
2020 "tools": [{"type": "web_search_20260209", "name": "web_search"}],
21 "messages": [{"role": "user", "content": "What'\''s the latest on the Mars rover?"}]
21 "messages": [{"role": "user", "content": "What is the latest on the Mars rover?"}]
2222 }'
2323 ```
2424
from line 25
2525 ```bash CLI
2626 ant messages create \
2727 --model claude-opus-5-5 \
28 --max-tokens 1024 \
28 --max-tokens 4096 \
2929 --tool '{type: web_search_20260209, name: web_search}' \
3030 --message '{role: user, content: "What is the latest on the Mars rover?"}'
3131 ```
from line 34
3434 client = anthropic.Anthropic()
3535 response = client.messages.create(
3636 model="claude-opus-5-5",
37 max_tokens=1024,
37 max_tokens=4096,
3838 tools=[{"type": "web_search_20260209", "name": "web_search"}],
39 messages=[{"role": "user", "content": "What's the latest on the Mars rover?"}],
39 messages=[{"role": "user", "content": "What is the latest on the Mars rover?"}],
4040 )
4141 print(response.content)
4242 ```
from line 45
4545 const client = new Anthropic();
4646 const response = await client.messages.create({
4747 model: "claude-opus-5-5",
48 max_tokens: 1024,
48 max_tokens: 4096,
4949 tools: [{ type: "web_search_20260209", name: "web_search" }],
50 messages: [{ role: "user", content: "What's the latest on the Mars rover?" }]
50 messages: [{ role: "user", content: "What is the latest on the Mars rover?" }]
5151 });
5252 console.log(response.content);
5353 ```
from line 58
5858 var parameters = new MessageCreateParams
5959 {
6060 Model = Model.ClaudeOpus5_5,
61 MaxTokens = 1024,
61 MaxTokens = 4096,
6262 Tools = [new ToolUnion(new WebSearchTool20260209())],
63 Messages = [new UserMessageParam { Content = "What's the latest on the Mars rover?" }]
63 Messages = [new UserMessageParam { Content = "What is the latest on the Mars rover?" }]
6464 };
6565
6666 var message = await client.Messages.Create(parameters);
from line 72
7272
7373 response, err := client.Messages.New(context.TODO(), anthropic.MessageNewParams{
7474 Model: anthropic.ModelClaudeOpus5_5,
75 MaxTokens: 1024,
75 MaxTokens: 4096,
7676 Tools: []anthropic.ToolUnionParam{
7777 {OfWebSearchTool20260209: &anthropic.WebSearchTool20260209Param{}},
7878 },
7979 Messages: []anthropic.MessageParam{
80 anthropic.NewUserMessage(anthropic.NewTextBlock("What's the latest on the Mars rover?")),
80 anthropic.NewUserMessage(anthropic.NewTextBlock("What is the latest on the Mars rover?")),
8181 },
8282 })
8383 if err != nil {
from line 94
9494
9595 MessageCreateParams params = MessageCreateParams.builder()
9696 .model(Model.CLAUDE_OPUS_5_5)
97 .maxTokens(1024L)
97 .maxTokens(4096L)
9898 .addTool(WebSearchTool20260209.builder().build())
99 .addUserMessage("What's the latest on the Mars rover?")
99 .addUserMessage("What is the latest on the Mars rover?")
100100 .build();
101101
102102 Message response = client.messages().create(params);
from line 109
109109
110110 $message = $client->messages->create(
111111 model: 'claude-opus-5-5',
112 maxTokens: 1024,
112 maxTokens: 4096,
113113 tools: [
114114 ['type' => 'web_search_20260209', 'name' => 'web_search'],
115115 ],
116116 messages: [
117 ['role' => 'user', 'content' => "What's the latest on the Mars rover?"],
117 ['role' => 'user', 'content' => 'What is the latest on the Mars rover?'],
118118 ],
119119 );
120120
from line 126
126126
127127 message = client.messages.create(
128128 model: Anthropic::Model::CLAUDE_OPUS_5_5,
129 max_tokens: 1024,
129 max_tokens: 4096,
130130 tools: [{ type: "web_search_20260209", name: "web_search" }],
131 messages: [{ role: "user", content: "What's the latest on the Mars rover?" }]
131 messages: [{ role: "user", content: "What is the latest on the Mars rover?" }]
132132 )
133133 puts message.content
134134 ```
from line 779
779779| Claude Sonnet 4 ([retired, except on Claude Models on Google Cloud (Google managed) and Bedrock](https://platform.claude.com/docs/en/about-claude/model-deprecations)) | 313 tokens | 315 tokens |
780780| Claude Haiku 5.5 | 286 tokens | 406 tokens |
781781| Claude Haiku 4.5 | 496 tokens | 588 tokens |
782| Claude Haiku 3.5 ([retired, except on Claude Models on Google Cloud (Google managed)](https://platform.claude.com/docs/en/about-claude/model-deprecations)) | 264 tokens | 355 tokens |
783782
784783* **auto, none:** The count when tool\_choice is auto or none.
785784* **any, tool:** The count when tool\_choice is any or tool.
No line in this hunk matches that.