Native Claude format

Anthropic's native Messages format interface, used for Claude series models. Compatible with /v1/messages.

Compatible with Anthropic Messages API. You can directly use the official anthropic SDK and set base_url to https://api.covanexus.com.

POST /v1/messages https://api.covanexus.com

Authorization

Body

Authorization

Authorization BearerAuth

Authorization Bearer <token>

Use Bearer Token authentication: Authorization: Bearer $COVA_NEXUS_API_KEY. Also compatible with Anthropic-style x-api-key: $COVA_NEXUS_API_KEY request header. anthropic-version: 2023-06-01 is required when using x-api-key.

in: header

Request Body

application/json

model* string

Model ID (e.g. claude-sonnet-4-5)

messages* array[object]

Conversation message list, each item contains role (user/assistant) and content

max_tokens* integer

Maximum number of generated Tokens

system? string | array[object]

System prompt

temperature? number

Sampling temperature

Default 1 | Range 0 ≤ value ≤ 1

top_p? number

Kernel sampling parameters

top_k? integer

Top-K sampling

stream? boolean

Whether to stream output (SSE event streaming)

Default false

stop_sequences? array[string]

stop sequence

tools? array[object]

List of available tools (tool calls)

tool_choice? object

Tool selection strategy

thinking? object

Extended thinking configuration (Claude model for supporting reasoning)

metadata? object

Custom metadata

Response Body

status code	Type
200	application/json
400	application/json
429	application/json

curl -X POST "https://api.covanexus.com/v1/messages" \
  -H "Authorization: Bearer $COVA_NEXUS_API_KEY" \
  -H "anthropic-version: 2023-06-01" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "claude-sonnet-4-5",
  "max_tokens": 1024,
  "messages": [
    {"role": "user", "content": "用一句话介绍你自己"}
  ]
}'

import Anthropic from "@anthropic-ai/sdk";

const client = new Anthropic({
  apiKey: "$COVA_NEXUS_API_KEY",
  baseURL: "https://api.covanexus.com"
});

const message = await client.messages.create({
  model: "claude-sonnet-4-5",
  max_tokens: 1024,
  messages: [
    { role: "user", content: "用一句话介绍你自己" }
  ]
});
console.log(message.content[0].text);

from anthropic import Anthropic

client = Anthropic(
    api_key="$COVA_NEXUS_API_KEY",
    base_url="https://api.covanexus.com"
)
message = client.messages.create(
    model="claude-sonnet-4-5",
    max_tokens=1024,
    messages=[
        {"role": "user", "content": "用一句话介绍你自己"}
    ]
)
print(message.content[0].text)

200

400

429

{
  "id": "msg_xxx",
  "type": "message",
  "role": "assistant",
  "model": "claude-sonnet-4-5",
  "content": [
    {
      "type": "text",
      "text": "string"
    }
  ],
  "stop_reason": "end_turn",
  "stop_sequence": null,
  "usage": {
    "input_tokens": 0,
    "output_tokens": 0,
    "cache_creation_input_tokens": 0,
    "cache_read_input_tokens": 0
  }
}

BearerAuth