DeepSeek Harness

Replace <BASE_URL> using values from Endpoints.

Use DeepSeek Harness with SupaNexus as a custom provider. The bundled DeepSeek card talks to DeepSeek’s own API — add a custom provider for the unified gateway.

Marketing landing page: DeepSeek API on SupaNexus.

Fill <BASE_URL> from Endpoints. Official Harness: deepseek.com/harness · GitHub.

How to use DeepSeek Harness with a custom API

Install DeepSeek Harness from the official developer preview. Pin a version you have tested — the preview still ships breaking changes.
Open Settings → Models and choose Add a custom provider. Catalog cards will not point at SupaNexus.
Set a lowercase Provider ID such as supanexus. The id is permanent for sessions and credentials.
Base URL: <BASE_URL>/v1. API protocol: OpenAI Chat Completions (openai-completions).
Paste a SupaNexus project API key.
Add models deepseek/deepseek-v4-pro and deepseek/deepseek-v4-flash, or choose Fetch available models (calls OpenAI-compatible GET /v1/models).
Save. For fields the form does not expose, edit $DSH_HOME/settings.yaml and restart.

llm-pi-ai:
  providers:
    supanexus:
      apiKeyEnv: SUPANEXUS_API_KEY
      api: openai-completions
      baseURL: "<BASE_URL>/v1"
      models:
        - id: deepseek/deepseek-v4-pro
        - id: deepseek/deepseek-v4-flash

Keep the key in SUPANEXUS_API_KEY. Do not commit it into YAML.

DeepSeek Harness recommended API

Item	Recommendation
Protocol	OpenAI Chat Completions (`openai-completions`) — native SupaNexus surface
Flagship / agents	`deepseek/deepseek-v4-pro`
Latency / cost	`deepseek/deepseek-v4-flash`
Global host	`https://api.supanexus.ai/v1`
CN backup	`https://api.supanexus.io/v1`

Use the official DeepSeek catalog card only when you intend to call DeepSeek’s own API. SupaNexus gives you one key across vendors, unified metering, and no DeepSeek peak / off-peak split on our catalog.

If the rest of your tools already speak Anthropic, you can point Harness at Messages (POST /v1/messages) instead. For a greenfield Harness setup, stay on Chat Completions.

OpenAI SDK (same models)

The same Public API IDs work outside Harness:

from openai import OpenAI

client = OpenAI(
    base_url="<BASE_URL>/v1",
    api_key="sk-snx-...",
)

response = client.chat.completions.create(
    model="deepseek/deepseek-v4-pro",
    messages=[{"role": "user", "content": "Hello!"}],
)
print(response.choices[0].message.content)

See also OpenAI SDK Integration and Models.