Harnesses and models

Pick the harness for each prompt with --provider. If you omit it, Boat uses the harness you chose on the Agents dashboard.

Harnesses

`--provider`	Harness	Models
`claude`	Claude Code	Anthropic models, or DeepSeek models on a DeepSeek key
`codex`	OpenAI Codex	OpenAI models, or DeepSeek models on a DeepSeek key
`pi`	pi	Anthropic, OpenAI, Mistral, and OpenRouter or llmgateway-routed models (DeepSeek and Mistral included)
`opencode`	OpenCode	same multi-vendor catalog
`prime`	Prime Agent	same multi-vendor catalog
`kimi`	Kimi Code CLI (Moonshot AI)	Kimi models: K3, Kimi for Coding, K2.7 Code, K2.6
`mistral`	Mistral Vibe (Mistral AI)	Mistral models: Large 4 (default), Medium 3.5, Small 4

For the keys each harness needs, read Keys and subscriptions.

The model catalog

Each model accepts a different set of reasoning levels. The catalog changes often, so Boat serves it live. This page does not list it.

boat prompt --help prints the catalog.
GET /provider-models returns it as JSON.

You can change the model or the thinking level on any prompt. The prompt stays in the same conversation.

boat prompt --provider pi --model claude-sonnet-5 --reasoning-effort high "Refactor the billing module"
boat prompt --model gpt-5.6-terra "Same task, second opinion"        # same conversation, other model

Fast mode

Fast mode runs the same model with faster output. The provider bills it at its higher fast rate.

Harness	Fast mode is	Speed	Billing
Codex	The “Fast” service tier	About 1.5x to 2x faster	Uses ChatGPT plan limits faster
Claude Code	Opus fast mode	Up to 2.5x faster	Billed from Claude usage credits

Only models with "fastMode": true in GET /provider-models accept it. Examples are GPT-6.1 Sol, GPT-6 Sol and Opus.
A prompt without fast uses the choice saved on the Agents dashboard.
fast: false forces standard speed.

boat prompt --provider codex --model gpt-6.1-sol --fast "Fix the failing tests"

curl -sS -X POST "$BOAT_API_BASE/sandboxes/$BOAT_ID/prompt" \
  -H "Authorization: Bearer $BOAT_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"provider":"codex","model":"gpt-6.1-sol","fast":true,"prompt":"Fix the failing tests"}'

await sandbox.prompt({ sandboxId, provider: "codex", model: "gpt-6.1-sol", fast: true, prompt: "Fix the failing tests" });

sandbox.prompt(sandbox_id, PromptRequest(provider="codex", model="gpt-6.1-sol", fast=True, prompt="Fix the failing tests"))

A model without fast mode refuses fast: true with 400 fast_mode_not_supported. The error message lists the models that have fast mode.

​Harnesses

​The model catalog

​Fast mode

Harnesses

The model catalog

Fast mode