Kimi API / Sep 24, 2026

Kimi K3 Prompt Cache Prefix Versioning for Long-Context API Budgets

Control Kimi K3 long-context spend with versioned prefixes, cache receipts, invalidation rules, output ceilings, and dated AIWave route evidence.

Keyword report: 2026-09-23Tier 1/2 developer focusSources checked Sep 24, 2026

This guide uses source checks from Sep 24, 2026. Provider and gateway prices can change; preserve the checked date with every forecast.

Why This Topic Matters Now

The Sep 23 report continued to show Kimi K3 and long-context intent. The distinct production problem is prefix lifecycle: a coding agent can reuse a large context efficiently only when the team knows which files produced the prefix, when the prefix became stale, and whether the gateway exposed a cached-input field. Without versioning, a lower token count can hide stale guidance rather than represent a reliable optimization.

This guide is a cache-governance pattern for Tier 1 and Tier 2 engineering teams. It keeps retrieval selection separate from prefix reuse, defines invalidation triggers, pins output ceilings, and records dated AIWave rate evidence beside provider documentation. The goal is not to promise a permanent cache behavior; it is to make each request explainable and each policy reversible.

Source Facts Checked Today

AIWave /api/pricing was checked from production on Sep 24, 2026 and returned HTTP 200, success=true, 73 live route rows, pricing_version a42d372ccf0b5dd13ecf71203521f9d2, auto_groups=['default'], group_ratio default=1 and vip=0.9. The public /api/v1/pricing endpoint returned HTTP 200 with 56 dated USD rows, pricing_version 83f77abde81ee3a096a672ed959ccc096f5d37a45c177ae8e03229456b5415a5, checked=2026-09-10, and updated_at=2026-09-18. Use the live response for route availability and the dated JSON for a forecast; they are not one interchangeable rate table.

The live AIWave route response checked on Sep 24, 2026 included kimi-k3 as an OpenAI-compatible route row. The live table establishes route availability metadata; it does not replace Kimi feature documentation or the dated gateway forecast.

The dated AIWave public pricing JSON checked in this run lists kimi-k3 at $4.50 input, $0.90 cache-hit input, and $22.50 output per 1M tokens, effective 2026-08-27. Keep cached input, uncached input, output, retrieval scope, and retries as separate ledger fields.

Kimi's API overview and pricing guide checked on Sep 24, 2026 document Kimi API usage and token-billing concepts. The provider pages are dynamic, so recheck them before publishing a direct-provider quote or changing a production cache promise; this article uses them as dated source links and policy context.

Planning Matrix

A source-dated planning matrix keeps the page useful for engineers and procurement reviewers. It turns a search query into an auditable route decision instead of a loose model preference.

Prefix eventCache policyReceipt evidence
Initial buildCreate from pinned files and policyfile versions and prefix hash
Stable reuseReuse only on matching versioncache fields and version
Code changeInvalidate affected prefixchanged files and reason
Policy changeInvalidate all dependent promptspolicy version and owner
Large outputKeep explicit ceilingfinish reason and output tokens
FallbackUse smaller context or approved routeattempt count and route ID

Implementation Pattern

The implementation pattern keeps credentials as placeholders, pins the AIWave base URL, records the model, and leaves room for route-specific controls. Production applications should move credentials into environment or secret storage.

from dataclasses import dataclass
from openai import OpenAI

client = OpenAI(
    api_key="YOUR_API_KEY_HERE",
    base_url="https://aiwave.live/v1",
)

@dataclass
class PrefixPolicy:
    model: str
    version: str
    max_files: int
    max_tokens: int

policy = PrefixPolicy(
    model="kimi-k3", version="repo-policy-v4", max_files=8, max_tokens=420
)
response = client.chat.completions.create(
    model=policy.model,
    messages=[{"role": "user", "content": "Review the selected redacted files."}],
    temperature=0.1,
    max_tokens=policy.max_tokens,
)
print({"prefix_version": policy.version, "max_files": policy.max_files,
       "finish": response.choices[0].finish_reason, "usage": response.usage})

Turn the Query Into a Contract

For a Kimi K3 prompt-cache prefix policy, define the request shape, model ID, data class, output ceiling, timeout, retry ceiling, owner, and source date before the first trial. A short contract gives engineering, security, and finance the same object to review when a provider changes a route or billing field.

Separate Live Routes From Dated Rates

The live AIWave pricing response answers which route rows and endpoint types are available at check time. The public pricing JSON is a dated USD snapshot for forecasting. Store both URLs, versions, checked dates, model IDs, and account-group context instead of presenting a volatile source as a permanent quote.

Use a Small Acceptance Set

A useful canary covers a normal request, a malformed request, a repeated prefix, a long output, a disconnect, and a deliberate stop condition. Record request ID, model ID, status, token usage, finish reason, retry count, and reviewer outcome. This turns a search result into evidence that can survive a route update.

Keep Data and Credentials Bounded

OpenAI-compatible clients reduce integration work, but they do not choose the right data boundary. Keep the credential server-side, use a visible placeholder in examples, redact fixtures, and attach a data-class decision to every route policy. Do not let a feature flag or model alias silently widen what crosses the API.

Make Recovery Observable

Retry only failures that are safe to retry and cap every fallback. Preserve the original request ID, mark the stop reason, and distinguish provider errors from client validation, policy rejection, and budget stops. Silent loops hide both reliability failures and billing variance.

Use AIWave's Evidence Layer

Use the Models docs, Chat Completions docs, dated Pricing JSON, and Status. Recheck the live route table before rollout, the dated pricing JSON before a budget review, the status page before a launch window, and the trust page before procurement. Keep each checked date visible in the record.

Release Gate

Promotion is ready when the provider source is dated, the AIWave route is rechecked, the acceptance set passes, the billing fields are understood, and a named owner can stop or reverse the change. If a field is unknown, label the work as a trial rather than production.

Source Links

Related AIWave Links