Models & environment

Which model runs

With a workspace provider, the one model saved on Settings › Models runs every session and every call. The fallback model is tried only when the primary model errors. See LLM transport. In operator mode, agent sessions run on Opus. That covers the Document scan, Flow setup and Flow generation sessions. A few steps make a single call instead, and each has its own default tier:

Stage	Environment override	Default
Matching a flow’s milestones to the interfaces that could realize them	`TRUECOURSE_MODEL_GUARD_MATCH`	sonnet
Deciding whether an edited section changed what it promises	`TRUECOURSE_MODEL_GUARD_CLAIM_DIFF`	sonnet
Proposing the recipe	`TRUECOURSE_MODEL_GUARD_RECIPE`	sonnet
Judging a failing web step’s screenshot	`TRUECOURSE_MODEL_GUARD_VISUAL_JUDGE`	opus

A stage resolves its model in this order:

its own TRUECOURSE_MODEL_<STAGE> variable;
TRUECOURSE_MODEL, for every stage at once;
its default.

CLAUDE_CODE_MODEL still works as an alias for TRUECOURSE_MODEL, and logs a deprecation line. TRUECOURSE_FALLBACK_MODEL names a model to retry with when the primary model is overloaded.

Environment variables

Set these in the server’s environment: the .env file at the root of the checkout, or the container’s environment.

Variable	What it does
`TRUECOURSE_MAX_CONCURRENCY`	How much runs in parallel. Agent sessions default to the smaller of the CPU count and 4. A Flow run’s test sandboxes default to the smaller of the CPU count and 8.
`TRUECOURSE_MAX_API_CONCURRENCY`	How many API servers a Flow run keeps booted at once. Defaults to the smaller of the sandbox limit and 3, and never exceeds the sandbox limit.
`TRUECOURSE_LLM_TIMEOUT_SCALE`	Multiplies every model call’s time ceiling. Defaults to 1. Raise it for a slow model or proxy.
`TRUECOURSE_LLM_STALL_TIMEOUT_MS`	Stops a streaming call that goes silent after its first event. Defaults to 300000, five minutes, multiplied by the timeout scale.
`TRUECOURSE_NO_PRICE_FETCH`	Model prices for cost estimates are fetched from OpenRouter at most once a day. Set this to skip the network and use the bundled list prices, for example on an air-gapped server.
`TRUECOURSE_GUARD_VISUAL_JUDGE`	Set to `1` or `true` to let a Flow run ask the model what a failing web step’s screenshot shows. The answer is an annotation and never changes an outcome. It uses the workspace’s model provider.

Getting Started

Workspace

Context

Code

Flows

Settings

Configuration

Enterprise

Models & environment

Which model runs

Environment variables

Next steps

LLM transport

Flow run

​Which model runs

​Environment variables

​Next steps

LLM transport

Flow run

Which model runs

Environment variables

Next steps