⚡ Claude Streaming Simulator

Test SSE event handling • token-by-token • raw events

✍️ Simulator

⏱️ TTFT: 📈 tok/s: ⏳ total: # tokens: 0

📡 Raw SSE events

Events will appear here …

event: content_block_delta • data: {type, delta}

🐍 Python (anthropic SDK)

from anthropic import Anthropic client = Anthropic(api_key="sk-...") with client.messages.stream( model="claude-sonnet-4-20250514", max_tokens=1024, messages=[{"role": "user", "content": "Hello"}] ) as stream: for event in stream: if event.type == "content_block_delta": print(event.delta.text, end="", flush=True)

🟨 JavaScript (fetch + ReadableStream)

const response = await fetch("https://api.anthropic.com/v1/messages", { method: "POST", headers: { "Content-Type": "application/json", "x-api-key": "sk-..." }, body: JSON.stringify({ model: "claude-sonnet-4-20250514", max_tokens: 1024, stream: true, messages: [{ role: "user", content: "Hello" }] }) }); const reader = response.body.getReader(); const decoder = new TextDecoder(); while (true) { const { done, value } = await reader.read(); if (done) break; const chunk = decoder.decode(value, { stream: true }); // parse SSE events: event: content_block_delta\ndata: {...} console.log(chunk); }