# Sell with an Anthropic API If your API already speaks the Anthropic Messages dialect, you can sell with no agent and no delivery endpoint. The exchange calls your API directly. To start, [log in](#log-in) with `dispatch_dialect` set to `anthropic`. - For an OpenAI-compatible API, see [Sell with an OpenAI-compatible API](https://inference.ai.exchange/docs/provider-openai.md). - To run an agent instead, see [Serve and get paid](https://inference.ai.exchange/docs/provider-dispatch.md). ## When to use this Use this path when your API streams a message in the Anthropic format. - You still keep the session open to quote. [Quote over the session](https://inference.ai.exchange/docs/provider-quoting.md) has the frames. - This path serves chat only. A job of another kind needs an agent, and the exchange offers it to the next offer. ## Set it up 1. Register the provider and its deployments. See [Register deployments](https://inference.ai.exchange/docs/provider-models.md). 2. Log in with `dispatch_dialect` set to `anthropic`. 3. Quote as usual. ### Log in `dispatch_url` is the base URL of your API. Its scheme, host and port must match the registered `declared_endpoint`. `dispatch_token` is the key of your API. The exchange sends it as `x-api-key` and keeps it in memory for this session only. ```json { "type": "login", "slug": "acme", "api_key": "sk-liquid-...", "dispatch_url": "https://api.acme.example/v1", "dispatch_token": "your-anthropic-api-key", "dispatch_dialect": "anthropic", "capabilities": [] } ``` ### Open the session and quote This script logs in, quotes each listed deployment and then sends a `heartbeat` every two seconds. The exchange closes a session that sends no frame for five seconds. See [Keep the session alive](https://inference.ai.exchange/docs/provider-quoting.md#keep-the-session-alive). The script uses the Python `websockets` package. A real provider also quotes again before the quote expires, and when its price changes. ```python import asyncio import json import websockets URL = "wss://router.inference.ai.exchange/v1/provider/ws" LOGIN = { "type": "login", "slug": "acme", "api_key": "sk-liquid-...", "dispatch_url": "https://api.acme.example/v1", "dispatch_token": "your-anthropic-api-key", "dispatch_dialect": "anthropic", "capabilities": [], } def quote(model_id: str, revision: int) -> dict: return { "type": "quote", "target": {"kind": "registered", "model_id": model_id}, "pricing": [ {"billable": "input_text", "unit": "mtok", "usd": 0.12}, {"billable": "output_text", "unit": "mtok", "usd": 0.48} ], "service_class": {"ttft_ms": 1500, "completion_ms": 30000}, "supported_features": ["text"], "retention_policy_supported": ["none"], "revision": revision, } async def beat(socket) -> None: while True: await asyncio.sleep(2) await socket.send(json.dumps({"type": "heartbeat"})) async def main() -> None: async with websockets.connect(URL) as socket: await socket.send(json.dumps(LOGIN)) beating = asyncio.create_task(beat(socket)) try: async for raw in socket: frame = json.loads(raw) print(frame["type"]) if frame["type"] == "listed": for model in frame["models"]: await socket.send(json.dumps(quote(model["model_id"], 1))) elif frame["type"] in ("login_reject", "quote_reject"): raise SystemExit(frame) finally: beating.cancel() asyncio.run(main()) ``` ## What the exchange sends The exchange posts a streamed message to `{dispatch_url}/messages`. The header `Idempotency-Key` is the award id. Your server may ignore it. The exchange never sends an award twice after the request leaves. ```bash curl https://api.acme.example/v1/messages \ -H "x-api-key: your-anthropic-api-key" \ -H "anthropic-version: 2023-06-01" \ -H "Idempotency-Key: aw_8f3c…" \ -H "Content-Type: application/json" \ -d '{ "model": "acme-claude-large", "max_tokens": 64, "stream": true, "messages": [{ "role": "user", "content": "Name a prime number." }] }' ``` - `model` is the upstream identifier of the deployment. - `max_tokens` is the cap of the award. - The exchange sends the cache plan of the job as `cache_control` markers, so cache writes are metered. - Thinking blocks, redacted thinking and tool calls pass through. Stream server-sent events in the Messages format, and end with `message_stop`. The exchange settles on the counts in `message_start.message.usage` and `message_delta.usage`. The last value of each count wins. ```text event: message_start data: {"type":"message_start","message":{"id":"msg_1","role":"assistant","usage":{"input_tokens":14,"cache_read_input_tokens":0,"cache_creation_input_tokens":0,"output_tokens":1}}} event: content_block_start data: {"type":"content_block_start","index":0,"content_block":{"type":"text","text":""}} event: content_block_delta data: {"type":"content_block_delta","index":0,"delta":{"type":"text_delta","text":"Seven is prime."}} event: content_block_stop data: {"type":"content_block_stop","index":0} event: message_delta data: {"type":"message_delta","delta":{"stop_reason":"end_turn"},"usage":{"output_tokens":5}} event: message_stop data: {"type":"message_stop"} ``` A stream with no usage counts, a stream that ends before `message_stop`, and an `error` event do not settle as a success. ## Refuse a job Answer an error with a status code of 400 or more before the first event, and the exchange offers the job to the next offer. ```http HTTP/1.1 529 Content-Type: application/json { "type": "error", "error": { "type": "overloaded_error", "message": "the deployment is at capacity" } } ``` After the first event of a chat answer, the exchange cannot fall back to another offer, because the buyer would get one answer from two providers. ## Limits - Only chat jobs are sent. A job of another kind goes to the next offer. - A chat job that has an audio or video part goes to the next offer, because the Messages API has no block for it. - Quote as usual. The `quote` frames do not change.