Call pi.setActiveTools() inside before_agent_start: 
pi.on('before_agent_start', async (_event, ctx) => {
  if (ctx.external?.conversationType === 'channel') {
    await pi.setActiveTools(['read', 'grep', 'lookup_customer']);
  }
});

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Rules

  • Pass an array containing at most 256 unique names.
  • Names must be non-empty, trimmed strings.
  • Every name must belong to the deployment’s allowed built-in or extension tool set.
  • An empty array intentionally disables all tools.
The method resolves to true when the selection is structurally accepted. Invalid selections throw. Salambo rejects names that are unavailable in the pinned deployment.

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Lifecycle

The hosted runtime applies active-tool selection from before_agent_start. Do not call this method during module discovery. The resulting set is persisted with session state and restored on durable follow-up turns. agent/settings.json remains the default for new sessions.