Routing - Twill

Routing configs decide how a new task runs when it arrives — from any surface. Each config is a row in Settings → Routing:

Field	Meaning
Trigger	The keyword that selects this config, written as `/keyword` (e.g. `ultra`)
Mode	`agent` (implement), `plan` (plan first), `ask` (read-only Q&A), or `goal` (iterate until a goal holds)
Agent	Which harness + model runs the task (e.g. Codex GPT 5.5)
Effort	`low`, `medium`, `high`, `xhigh` — plus `ultracode` on Claude Code

Every workspace has an undeletable default config — the fallback when no trigger matches. New workspaces default to agent mode, Codex GPT 5.5, medium effort. Configs can also carry custom instructions appended to the task.

Using triggers

Start a task message with the trigger:

@twill /ultra fix the race condition in the export worker

The trigger is stripped before the agent sees the message. How a trigger fires depends on the surface:

Surface	How to fire a config
Web app	Pick mode/agent directly in the composer
Slack, Notion, Asana	`/trigger` at the start of the message
GitHub	`/trigger` in the text, or an issue label matching the trigger
Linear	An issue label matching the trigger

Routing applies to a task’s first message only. Follow-ups keep the task’s existing agent and mode.

Bring your own keysRun tasks on your own provider API keys at provider rates — Twill bills nothing for the AI usage.

​Using triggers

Using triggers