Endpoints

Anthropic Messages API

An Anthropic-compatible /v1/messages endpoint so the Anthropic SDKs and Claude Code work out of the box.

POST /v1/messages

curl https://api.pendra.ai/v1/messages \
  -H "x-api-key: pdr_sk_..." \
  -H "anthropic-version: 2023-06-01" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "qwen3.6:27b",
    "max_tokens": 1024,
    "messages": [
      { "role": "user", "content": "Hello!" }
    ]
  }'

from anthropic import Anthropic

client = Anthropic(
    api_key="pdr_sk_...",
    base_url="https://api.pendra.ai",
)

msg = client.messages.create(
    model="qwen3.6:27b",
    max_tokens=1024,
    messages=[{"role": "user", "content": "Hello!"}],
)
print(msg.content[0].text)

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

const client = new Anthropic({
  apiKey: 'pdr_sk_...',
  baseURL: 'https://api.pendra.ai',
});

const msg = await client.messages.create({
  model: 'qwen3.6:27b',
  max_tokens: 1024,
  messages: [{ role: 'user', content: 'Hello!' }],
});
console.log(msg.content[0].text);

200

{
  "id": "msg_01N3Xc8...",
  "type": "message",
  "role": "assistant",
  "model": "qwen3.6:27b",
  "content": [
    {
      "type": "text",
      "text": "Hello! How can I help?"
    }
  ],
  "stop_reason": "end_turn",
  "stop_sequence": null,
  "usage": {
    "input_tokens": 9,
    "output_tokens": 12
  }
}

Pendra translates Anthropic's Messages format to OpenAI Chat Completions under the hood, so you can point any Anthropic SDK — or Claude Code — at Pendra and get Anthropic-shaped responses back. The Python and JavaScript examples use the official Anthropic SDKs; only the base URL and key change.

Authentication

Send your Pendra API key on the x-api-key header (Anthropic convention). The Authorization: Bearer header also works for OpenAI-style clients.

Body application/json

model string required

Model ID. Browse available models.

max_tokens integer required

Maximum number of tokens to generate.

messages array required

The conversation — an array of { role, content } objects.

system string | array

System prompt — a string, or an array of content blocks.

stream boolean default: false

Set true for Anthropic-format SSE (see Streaming below).

tools array

Anthropic-shaped tool definitions. Pair with tool_choice.

Other optional fields

temperature, top_p, top_k, stop_sequences — standard sampling controls.

Response

Pendra returns the Anthropic message envelope (see example). content is an array of content blocks (text, tool_use, etc.). stop_reason is "end_turn" on a natural finish or "max_tokens" when capped. usage uses Anthropic naming (input_tokens / output_tokens).

Streaming

Set "stream": true to receive Anthropic-format SSE events (message_start, content_block_delta, message_delta, message_stop).

event: message_start
data: {"type":"message_start","message":{"id":"msg_01N3Xc8","type":"message","role":"assistant","content":[],"model":"qwen3.6:27b","stop_reason":null,"usage":{"input_tokens":9,"output_tokens":0}}}

event: content_block_delta
data: {"type":"content_block_delta","index":0,"delta":{"type":"text_delta","text":"Hello"}}

event: message_delta
data: {"type":"message_delta","delta":{"stop_reason":"end_turn","stop_sequence":null},"usage":{"output_tokens":2}}

event: message_stop
data: {"type":"message_stop"}

Use with Claude Code

Point Claude Code at Pendra by setting two environment variables — see the full recipe in Integrations → Claude Code.