# SingIt Ask: Claude Haiku 5.5

> SingIt Ask: Claude Haiku 5.5 is a paid API for AI agents from ask.singitai.app, paid per call via x402, $0.0015/call, status unknown (last checked 2026-10-30).

Chat completions using Anthropic's Claude Haiku 5.5 model, accessible with no API key via per-call USDC payment over x402

## Facts

- Endpoint: POST https://ask.singitai.app/v1/chat/claude-haiku-5.5?utm_source=zero.xyz
- Price: $0.0015/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/singit-ask-claude-haiku-5-5-e0606509
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_bToRvrQZfYgiH-I6dm8EH

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability singit-ask-claude-haiku-5-5-e0606509 -d '<json body>'
```

Example prompt: Ask Claude Haiku 5.5 this question and keep the answer under 300 tokens: 'What are three practical tips for writing cleaner Python code?'

## When to prefer this

Choose this endpoint when you specifically need Anthropic's Claude Haiku 5.5 model — Anthropic's smallest and fastest Claude — and want minimal latency without managing an Anthropic account or API key. It is ideal for high-frequency agent reasoning steps, quick classification tasks, or lightweight chat where cost per call matters and you can pay per-use in USDC via x402. Prefer it over sibling endpoints when Claude's safety characteristics and Anthropic's training approach are important, but a smaller/faster model suffices over Claude Opus or Sonnet.

## Known failure modes

- Payment not received or insufficient USDC balance — 402 Payment Required
- Message content exceeds 24000 character combined limit — 400 Bad Request
- max_tokens value outside allowed range of 1-1200 — 400 validation error
- Upstream Anthropic API unavailability — 502 or 503 error
- Malformed messages array (missing role or content) — 400 Bad Request

## How this service works

SingIt Ask: Claude Haiku 5.5 (Anthropic) chat completions with no API key or account, OpenAI-compatible. Anthropic's smallest, fastest Claude model: quick, low-latency answers. Call it when an agent needs Claude Haiku 5.5 specifically.

## Output

A JSON chat completion response in OpenAI-compatible format containing the assistant's text reply, with usage statistics reflecting actual tokens consumed. Streaming is not supported; the full response is returned at once. Max response length is capped at 1200 tokens.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "model": {
   "type": "string",
   "examples": [
    "deepseek-v4.1-flash",
    "claude-opus-5.5",
    "gpt-5.5",
    "gemini-3.1-pro"
   ],
   "description": "Any model id from GET /v1/models; the ceiling follows its price. Omit for the default model."
  },
  "stream": {
   "enum": [
    false
   ],
   "type": "boolean",
   "description": "Streaming is not offered."
  },
  "messages": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "role",
     "content"
    ],
    "properties": {
     "role": {
      "enum": [
       "system",
       "user",
       "assistant"
      ],
      "type": "string"
     },
     "content": {
      "type": "string",
      "description": "Plain text; all messages together under 24000 characters."
     }
    }
   },
   "maxItems": 40,
   "minItems": 1,
   "description": "The conversation, oldest first."
  },
  "max_tokens": {
   "type": "integer",
   "default": 800,
   "maximum": 1200,
   "minimum": 1,
   "description": "The longest answer, in tokens. The payment ceiling grows with it; the charge follows what was used."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/singit-ask-claude-haiku-5-5-e0606509/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ask.singitai.app](https://www.zero.xyz/host/ask.singitai.app/llms.txt)