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Claude Haiku 5.5 via x402engine
x402
Claude Haiku 5.5 via x402engine is a paid API for AI agents from x402engine.app, paid per call via x402, $0.00829/call, status unknown (last checked 2026-10-12).
Calls Anthropic's Claude Haiku 5.5 model (small, fast, cost-efficient) for high-volume tasks like summarization, coding, and subagent use via pay-per-call micropayment
Price / call$0.00829
Success—
StatusUnknown
How this service works
x402engine — Claude Haiku 5.5 is Anthropic's small, fast model for high-volume, cost-sensitive work such as summarization, subagents, and browser use. It succeeds Claude Haiku 4.5 with stronger coding, computer use, and...
Output
Returns an OpenAI-compatible JSON response with the model name (anthropic/claude-haiku-5.5), an array of choices each containing an assistant message with role and content, a finish_reason (e.g. 'stop'), and a top-level 'content' field with the text response.
Example use cases
Batch summarization for high-volume pipelines
“I have 500 customer support tickets I need summarized into one sentence each — use Claude Haiku 5.5 since it's fast and cost-efficient, and process each one with the system prompt: 'Summarize this support ticket in one sentence.'”
Subagent reasoning step in agentic workflow
“As part of my research agent, call Claude Haiku 5.5 with this message array to decide which of three next actions to take — the system message is 'You are a decision-making subagent' and the user message is 'Given these three options, which should I do next: A, B, or C?'”
Fast code generation for automation scripts
“Use Claude Haiku 5.5 to write me a Python script that parses a CSV file and outputs rows where the 'status' column equals 'failed' — I want it quick, just give me the code.”
Technical details
Endpoint
POSThttps://x402engine.app/api/llm/claude-haiku-5.5?utm_source=zero.xyzWhen to prefer
Choose this endpoint when you need Anthropic's Claude Haiku 5.5 specifically for high-volume, latency-sensitive, or cost-sensitive workloads such as batch summarization, classification, subagent decisions, or coding tasks — and you want pay-per-call pricing via x402 micropayment without managing an Anthropic API subscription. Prefer Claude Opus or Sonnet endpoints for complex reasoning or very long context tasks.
Side effects
- Payment not settled — 402 returned before inference runs
- Input messages array missing or malformed — validation error
- Token limit exceeded for the model's context window
- Tool call schema invalid — function definitions malformed
- Streaming requested but connection dropped mid-SSE stream
- Model unavailable or upstream Anthropic outage — 503 or timeout
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Output
Schema · Response
{
"type": "json",
"example": {
"model": "anthropic/claude-haiku-5.5",
"choices": [
{
"index": 0,
"message": {
"role": "assistant",
"content": "Hello!"
},
"finish_reason": "stop"
}
],
"content": "Hello!"
}
}Tags
x402
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