# Models How TaskStation picks a model, and how billing works for managed vs. your-own-key models. Canonical page: https://taskstation.co/docs/project/models TaskStation runs each [session](/docs/work/sessions) on a model. This page explains managed models vs. your own provider key (BYOK), how TaskStation picks a model automatically, and two billing gotchas to know. This page applies to projects with the LLM Gateway on. LLM Gateway is an experimental [feature flag](/docs/feature-flags), **on by default** where the platform offers it — check or toggle it in Settings → Experimental (operators can default a whole deployment off with `LLM_GATEWAY_DEFAULT_ENABLED=false`). Turning the flag off is a fully supported path. The project then runs **native OpenCode model management**: - Your provider API keys (`ANTHROPIC_API_KEY`, `OPENAI_API_KEY`, `OPENROUTER_API_KEY`, …) are injected into the sandbox as ordinary env vars — add them on the Model settings page or as [secrets](/docs/project/secrets). OpenCode connects each provider from its key automatically. - Model ids are OpenCode's native `provider/model` refs, like `anthropic/claude-opus-4-8`. Managed bare ids and `taskstation/…` refs do not exist off-gateway. - The model picker shows one list before and after the sandbox boots: the providers your keys connect, plus OpenCode Zen's free models (OpenCode connects those without a key). Thinking effort is the composer's thinking control (the model's own variants); the gateway's Generation defaults do not apply. - The gateway surfaces on this page — managed models, the model-defaults chain, budgets, logs — do not apply; OpenCode resolves the default model in the sandbox. ## Managed models and BYOK A model id has one of three shapes: - **Managed** — a bare id, like `grok-4.6` or `deepseek-v4-pro-0813`. TaskStation supplies the credentials. Cloud accounts pay with TaskStation credits. - **BYOK** — a `provider/model` id, like `anthropic/claude-opus-4-8`. You supply the key. Your provider account pays. - **ChatGPT** — a `codex/` id. You connect your ChatGPT plan once through OAuth, and it pays. Connect a BYOK key on the project's Model settings page, or set the provider's env var directly as a [secret](/docs/project/secrets). ## Thinking effort The composer's thinking control sets the session's model **variant** in both modes. The choices are the model's own published tiers (models.dev `reasoning_options`), never a fixed ladder; a model without a knob shows no control. `Auto` clears the variant. - Native (gateway off): OpenCode applies the variant as the provider's own request field. - Gateway on: the request carries `reasoning_effort`; the gateway maps it per upstream (OpenAI → `reasoning_effort`, Claude → adaptive thinking, OpenAI on Amazon Bedrock → Bedrock's `reasoning.effort` request field). For an upstream it cannot map yet (Nova, Grok on Bedrock today) the value is dropped and the model runs at its own default. - Amazon Bedrock refuses the bare in-region id of most current models ("on-demand throughput isn't supported"). The picker prefers the `global.` / regional inference-profile id when the catalog carries one, and the gateway retries a refused bare id once per profile prefix (`global.`, `us.`). - The sandbox learns the project's servable model set from the API at every boot (`GET /v1/llm/models?scope=picker`, the same composition as the web picker), so a model the picker offers always resolves in the runtime. - A project default per model lives in Customize → Gateway → Routing → **Generation defaults** (`model_generation_config`). It fills only a field the request left unset, so a session's variant always wins. ## How auto picks a model Set no model, and TaskStation resolves one through five layers, in order. (The id `auto` covers this same behavior, but it is not yet a selectable option in the model picker.) 1. An explicit pin — a session, channel, or trigger's own `model:` field. 2. The [agent's](/docs/project/agents) default for this project. 3. The project's default. 4. The account's default. 5. The platform default. TaskStation uses the first layer that has a value it can still serve. A saved default that stops working — a disconnected key, a retired model — is skipped automatically. A session never dies from a stale default. See the [manifest reference](/docs/project/manifest) for the trigger `model:` field. > **Billing surprises on BYOK** > Two costs are easy to miss on a paid cloud account: > > - **Platform fee.** TaskStation adds a 10% fee, billed as credits, on top of what > your own provider charges. Free-tier and self-hosted accounts are exempt. > - **Silent failover.** If your BYOK key hits a rate limit or billing error > mid-turn, TaskStation retries on a managed model and bills your credits instead > of failing the session. > > If you see credit charges on a BYOK-only project, check these two causes > before reporting a billing bug. ## Per-project model enablement The project controls which models its pickers offer. By default, the newest model of each family is offered automatically. TaskStation-managed models and any model your project's defaults or routing policy reference are always offered — a guard never prunes them. You can override the default for individual models on the **Manage models** page (Customize → Models). An exception is stored per project and takes effect immediately. The session model picker and the command palette hide anything you turn off; new models stay on by default as the catalog grows. Enablement governs what is offered, not what is served: a request that names a disabled model outright (for example through the raw API) still runs. The project's default model cannot be turned off — set a different default first. ## Shared, not private, keys A connected provider key applies to the whole project. There is no private, per-user key — setting a personal override for a provider key fails with a `llm_credentials_project_wide` error. Update the shared key on the [secrets](/docs/project/secrets) page instead.