> ## Documentation Index
> Fetch the complete documentation index at: https://docs.replicas.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# DeepSeek Harness

> Run OpenRouter-backed DeepSeek Harness agents in Replicas workspaces.

Replicas supports [DeepSeek Harness](https://github.com/deepseek-ai/DeepSeek-Harness) as a coding agent. The official DSH runtime runs inside the workspace and uses OpenRouter for inference.

## Setup

1. Create a key on the [OpenRouter keys page](https://openrouter.ai/keys).
2. Paste it under **DeepSeek Harness → OpenRouter API Key** in [Organization → Coding Agents](https://replicas.dev/dashboard/agents).
3. Set an organization credential for the team, or add a personal key under **Personal** to override it.

The OpenRouter key and enabled-model selection are shared with [Opencode](/features/coding-agents/opencode) and [Pi](/features/coding-agents/pi). See [Credentials](/admin/credentials) for credential scope and fallback behavior.

## Models

Organization admins choose models under **DeepSeek Harness → OpenRouter models** in [Coding Agents settings](https://replicas.dev/dashboard/agents). Until changed, Replicas enables:

| Model ID                          | Label             | Notes                        |
| --------------------------------- | ----------------- | ---------------------------- |
| `deepseek/deepseek-v4-pro-0813`   | DeepSeek V4 Pro   | Default                      |
| `deepseek/deepseek-v4-flash-0731` | DeepSeek V4 Flash | Faster V4 model              |
| `z-ai/glm-5.2`                    | GLM 5.2           | General agentic coding       |
| `stealth/ox-alpha`                | Ox Alpha          | Free stealth reasoning model |
| `minimax/minimax-m3`              | MiniMax M3        | Long-context agentic coding  |
| `xiaomi/mimo-v2.5-pro`            | MiMo V2.5 Pro     | Agent-focused Xiaomi model   |
| `moonshotai/kimi-k2.6`            | Kimi K2.6         | Multimodal coding model      |

Choose an organization default under [Defaults](/admin/defaults), a personal default in account preferences, or a model for the active chat from the workspace composer.

## Using DeepSeek Harness in Workspaces

Choose **DeepSeek Harness** from the composer's agent picker. It can:

* Read, write, and edit repository files
* Run shell commands and show tool activity in chat
* Accept image attachments
* Ask questions in the composer
* Use [Plan Mode](/features/workspaces/plan-mode)
* Discover skills and expose them as slash commands
* Persist sessions, tool history, jobs, and context usage across turns
* Steer a queued message into the active turn
* Interrupt an active turn

DeepSeek Harness runs with full workspace access and does not request approval before using tools.

DeepSeek Harness does not support Fast Mode or Codex goal mode.

## Programmatic Use

Select DeepSeek Harness anywhere Replicas accepts a coding agent:

| Surface                              | How to choose DeepSeek Harness                                              |
| ------------------------------------ | --------------------------------------------------------------------------- |
| [CLI](/features/cli)                 | `-a deepseek` on `replicas create` and `replicas send`                      |
| [API](/features/api)                 | `"coding_agent": "deepseek"` on create and message requests                 |
| [MCP](/features/mcp)                 | `"coding_agent": "deepseek"` on `create_replica` and `send_replica_message` |
| [Automations](/features/automations) | Set **Coding agent** to DeepSeek Harness                                    |
| [Defaults](/admin/defaults)          | Select DeepSeek Harness as the organization or personal default             |

```bash theme={null}
replicas create fix-tests \
  -e backend \
  -a deepseek \
  -m "Inspect the repository and fix the failing tests"

replicas send REPLICA_ID \
  -a deepseek \
  -m "Run the tests and address any remaining failures"
```

```bash theme={null}
curl -X POST "https://api.replicas.dev/v1/replica" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "fix-tests",
    "environment_id": "ENVIRONMENT_UUID",
    "message": "Inspect the repository and fix the failing tests",
    "coding_agent": "deepseek",
    "model": "deepseek/deepseek-v4-pro-0813"
  }'
```