⚠️ 待更新·2026-08-29核验 · 更新时间待核验 · 本文信息可能已过期，请以官方文档为准
更新时间：2026-08-29 · 核验状态：待更新 · 官方溯源待补
引言
Anthropic 通过官方 API 与 Partner（AWS Bedrock、Google Vertex）提供 Claude 访问。新用户在 console.anthropic.com 注册可获 $5 免费试用额度，足以评测各模型在长文本、代码、代理编排上的表现。
模型与端点
端点：https://api.anthropic.com/v1/messages。Headers：x-api-key、anthropic-version: 2023-06-01。
claude-3-5-sonnet-20241022 — 综合最强。claude-3-5-haiku-20241022 — 快、便宜。claude-3-opus-20240229 — 旗舰（较少推荐）。
调用示例
import anthropic
client = anthropic.Anthropic(api_key="sk-ant-...")
msg = client.messages.create(
model="claude-3-5-sonnet-20241022", max_tokens=1024,
messages=[{"role": "user", "content": "用三个要点解释 RAG 的核心步骤"}])
print(msg.content[0].text)
注意事项
试用额度仅新账号一次性发放；RPM 与上下文受档位约束（Sonnet 50 RPM）。$5 按 Sonnet 输入 $3/百万 token 计约百万 token 调用量。生产走正式计费。Claude 在 200K 上下文、工具调用、安全对齐上优秀。企业可走 Bedrock/Vertex 统一计费。
⚠️ Pending Update · 2026-08-29 Verification · Content may be outdated, please refer to official docs
Updated: 2026-08-29 · Status: Pending Verification
Introduction
Anthropic offers Claude through its official API and via partners (AWS Bedrock, Google Vertex, Google AI Studio). New accounts on console.anthropic.com receive a $5 free trial credit, enough to evaluate each model on long-context understanding, code generation, and agent orchestration before committing to a paid plan. Claude is particularly strong on three axes: 200K-token context windows, reliable tool use, and conservative safety alignment — which makes it a favorite for document analysis, coding agents, and regulated workloads where a refusal is preferable to a wrong answer. Claude also leads on agentic reliability: its tool-use format is strict and well-documented, and the model rarely produces malformed tool calls compared to more permissive models. For multi-step agent workflows where a single malformed call can derail an entire run, this reliability is often worth the premium, and the free trial is the right place to measure it against your specific tool definitions.
Models and Endpoint
Endpoint: https://api.anthropic.com/v1/messages. Required headers: x-api-key and anthropic-version: 2023-06-01.
claude-3-5-sonnet-20241022 — strongest all-around, the default choice.claude-3-5-haiku-20241022 — fast and cheap, good for high-volume classification.claude-3-opus-20240229 — legacy flagship, less recommended now that Sonnet exceeds it.
Call Example
import anthropic
client = anthropic.Anthropic(api_key="sk-ant-...")
msg = client.messages.create(
model="claude-3-5-sonnet-20241022", max_tokens=1024,
messages=[{"role": "user", "content": "Explain the core steps of RAG in three bullet points."}])
print(msg.content[0].text)
Caveats
The trial credit has three limits. First, it is granted once to new accounts only — there is no recurring free tier, so plan your evaluation to use the credit deliberately rather than frittering it on exploratory calls. Second, RPM and context length depend on model tier (Sonnet allows 50 RPM, Haiku more). Third, the $5 credit at Sonnet's $3 per million input tokens covers roughly a million tokens of input — enough for evaluation, not for sustained production. For production, switch to standard billing. Enterprises often prefer the Bedrock or Vertex partner channels, which bill through the cloud provider and simplify procurement, IAM, and compliance. A final note on prompt caching: Anthropic supports explicit prompt caching on the paid tier, which dramatically reduces cost for repetitive long-context workloads like document Q&A over a fixed corpus. The free trial does not support caching, so your trial-period cost numbers will overstate production cost for caching-friendly workloads — factor that into any business case you build from trial data, or you may under-estimate the migration's ROI. Treat the trial as a structured evaluation rather than open-ended exploration, because a deliberate plan extracts far more signal per dollar of credit than ad-hoc prompting.