Claude Haiku 4.5·续

Claude Haiku 4.5·续

curl https://api.cloudflare.com/client/v4/accounts/$CLOUDFLARE_ACCOUNT_ID/ai/v1/messages \
  --header "Authorization: Bearer $CLOUDFLARE_API_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "model": "anthropic/claude-haiku-4.5",
  "max_tokens": 1024,
  "messages": [
    {
      "content": "Explain the concept of recursion with a simple example.",
      "role": "user"
    }
  ],
  "stream": true
}'

# Recursion Explained

**Recursion** is when a function calls itself to solve smaller instances of the same problem until it reaches a simple base case.

## Key Components

1. **Base Case**: The condition that stops the recursion
2. **Recursive Case**: The function calling itself with a simpler input

## Simple Example: Factorial

Calculate 5! (5 × 4 × 3 × 2 × 1)

```python
def factorial(n):
    # Base case: stop here
    if n == 1:
        return 1

    # Recursive case: break problem into smaller piece
    return n * factorial(n - 1)

print(factorial(5))  # Output: 120
```

### How It Works

```
factorial(5)
→ 5 * factorial(4)
  → 4 * factorial(3)
    → 3 * factorial(2)
      → 2 * factorial(1)
        → return 1  [BASE CASE]
      → return 2 * 1 = 2
    → return 3 * 2 = 6
  → return 4 * 6 = 24
→ return 5 * 24 = 120
```

## Real-World Analogy

It's like opening Russian nesting dolls:
- Open a doll → find a smaller doll inside
- Open that doll → find an even smaller one
- Keep going until you reach the tiniest doll (base case)
- Now work backwards: you've reached the smallest piece

## Why Use Recursion?

✅ **Good for**: Problems with naturally recursive structure (trees, nested data, divide-and-conquer)  
⚠️ **Caution**: Can be slow and cause stack overflow if not careful

Recursion is elegant but always ensure you have a clear base case!

[
  {
    "message": {
      "content": [],
      "id": "msg_01KvQp2GZvMb9V166tjgWh8q",
      "model": "claude-haiku-4-5-20251001",
      "role": "assistant",
      "stop_details": null,
      "stop_reason": null,
      "stop_sequence": null,
      "type": "message",
      "usage": {
        "cache_creation": {
          "ephemeral_1h_input_tokens": 0,
          "ephemeral_5m_input_tokens": 0
        },
        "cache_creation_input_tokens": 0,
        "cache_read_input_tokens": 0,
        "inference_geo": "not_available",
        "input_tokens": 19,
        "output_tokens": 2,
        "service_tier": "standard"
      }
    },
    "type": "message_start"
  },
  {
    "content_block": {
      "text": "",
      "type": "text"
    },
    "index": 0,
    "type": "content_block_start"
  },
  "... 19 more chunks omitted ...",
  {
    "type": "message_stop"
  }
]

</details>

<summary>Web Search — Letting Claude use Anthropic's server-side web search tool to answer with current information</summary>

const response = await env.AI.run(
  'anthropic/claude-haiku-4.5',
  {
    max_tokens: 4096,
    messages: [
      {
        content:
          'What were the top news stories about Cloudflare this week? Summarise in three bullets.',
        role: 'user',
      },
    ],
    tools: [{ max_uses: 3, name: 'web_search', type: 'web_search_20250305' }],
  },
)
console.log(response)

curl https://api.cloudflare.com/client/v4/accounts/$CLOUDFLARE_ACCOUNT_ID/ai/v1/messages \
  --header "Authorization: Bearer $CLOUDFLARE_API_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "model": "anthropic/claude-haiku-4.5",
  "max_tokens": 4096,
  "messages": [
    {
      "content": "What were the top news stories about Cloudflare this week? Summarise in three bullets.",
      "role": "user"
    }
  ],
  "tools": [
    {
      "max_uses": 3,
      "name": "web_search",
      "type": "web_search_20250305"
    }
  ]
}'

Let me search for more recent news from this week specifically.

{
  "id": "msg_01NgyYq84DqRm9gyaizK2pMV",
  "type": "message",
  "role": "assistant",
  "content": [
    {
      "type": "server_tool_use",
      "id": "srvtoolu_01R5mdFCHNmfZ1M66S6yRNnU",
      "name": "web_search",
      "input": {
        "query": "Cloudflare news this week 2026"
      }
    },
    {
      "type": "web_search_tool_result",
      "tool_use_id": "srvtoolu_01R5mdFCHNmfZ1M66S6yRNnU",
      "content": [
        {
          "type": "web_search_result",
          "title": "Agents Week 2026 Updates and Announcements | Cloudflare",
          "url": "https://www.cloudflare.com/agents-week/updates/",
          "encrypted_content": "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",
          "page_age": "May 18, 2026"
        },
        {
          "type": "web_search_result",
          "title": "Cloudflare Status",
          "url": "https://www.cloudflarestatus.com/",
          "encrypted_content": "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
... response truncated ...

</details>

Parameters

▶messages[]

arrayrequired

max_tokens

numberrequiredexclusiveMinimum: 0

system

string

temperature

numberminimum: 0maximum: 1

top_p

numberminimum: 0maximum: 1

top_k

numberexclusiveMinimum: 0

stream

boolean

▶metadata{}

object

string

type

stringconst: message

role

stringconst: assistant

▶content[]

array

model

string

stop_reason

string

▶usage{}

object

API Schemas (Raw)

Input Open Download

Output Open Download

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description: Claude Haiku 5.5 is a fast, cost-efficient model for high-volume, latency-sensitive tasks such as classification, extraction, routing, and subagent work. title: Claude Haiku 5.5 image: https://developers.cloudflare.com/og-docs.png

Documentation Index
Fetch the complete documentation index at: https://developers.cloudflare.com/llms.txt
Use this file to discover all available pages before exploring further.

Claude Haiku 4.5·续

Claude Haiku 4.5·续

Parameters

API Schemas (Raw)

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