moonshot API

What it is. The Moonshot AI (Kimi) API serves the Kimi K-series at api.moonshot.ai, exposing OpenAI-compatible Chat Completions and Responses plus an Anthropic-compatible Messages endpoint. Why it matters. It is the developer path to Kimi K3’s 1M-token input and output context — the database’s only full-window output ceiling. Key characteristics. Separate reasoning_content and content stream deltas; K3 uses reasoning_effort (low/high/max) while K2.x uses thinking; JSON mode / structured output, automatic context caching, file upload (text/image/video). What a professional should know. Temperature and top_p are fixed for K3 and K2.x (not tunable), and rate limits/regions are published behind a JS-rendered page that could not be extracted into structured data.

The Moonshot AI (Kimi) API serves the Kimi K-series at api.moonshot.ai. It exposes OpenAI-compatible Chat Completions (/v1/chat/completions), OpenAI Responses (/v1/responses) and an Anthropic-compatible Messages endpoint (/anthropic/v1/messages), plus files, batches, tokenizer and web-search tools.

Streaming is SSE with separate reasoning_content and content deltas. kimi-k3 uses top-level reasoning_effort (low/high/max, default max); K2.x models use the thinking parameter. JSON mode / structured output, automatic context caching and file upload (text/image/video) are supported. Temperature and top_p are fixed for K3 and K2.x. Serving regions are not stated in the fetched docs.

Why it matters

The Kimi API matters as the long-context-generation path: Kimi K3’s 1M-token output ceiling — unique in the database — is only reachable through this API, making it the reference surface for long-form generation and whole-repo rewriting. The cost trade-off is the premium: $3.00/$15.00 per 1M tokens for kimi-k3, the highest input/output pricing among the non-Doubao flagships. China AI Hub analysis indicates the API’s structural role is the long-output specialist, with fixed sampling parameters (temperature/top_p) as the notable constraint for teams that normally tune generation.

Labels used above: Official fact (from the Kimi API overview and Chat Completions spec), Vendor-reported claim (pricing and capability statements by Moonshot AI), and China AI Hub analysis (our synthesis, always introduced as such).