add checkpoint deployment cli support

[kevinjosethomas]

• adds checkpoint deployment to the existing deployments create command with an explicit checkpoint id flag.
• reuses the deployments api client so checkpoint deployment returns and displays the created adapter.
• covers the endpoint call, success output, and conflict error behavior in deployment cli tests.

---

Note

Low Risk
Additive CLI/API client wiring with tests; no changes to auth or existing adapter deploy validation paths beyond a new optional flag.

Overview
Adds Hosted Training checkpoint deployment to the Prime CLI so users can start inference from a checkpoint without going through an existing adapter ID first.

DeploymentsClient gains deploy_checkpoint, which POSTs to /rft/checkpoints/{id}/deploy and parses the returned adapter like adapter deploy. prime deployments create accepts --checkpoint-id (mutually exclusive with positional MODEL_ID), runs confirmation unless --yes, prints adapter id/status, and reuses the same inference usage hints as model deploy.

The checkpoint path does not run the READY / deployable-base-model checks used for adapter deploy; it relies on the API. Tests cover the POST path, successful CLI output, and surfacing 409 conflict errors.

^{Reviewed by Cursor Bugbot for commit 13d3303. Bugbot is set up for automated code reviews on this repo. Configure here.}

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

^{❌ Bugbot Autofix is OFF. To automatically fix reported issues with cloud agents, enable autofix in the Cursor dashboard.}

^{Reviewed by Cursor Bugbot for commit 13d3303. Configure here.}

[cursor]

Empty checkpoint-id triggers assert

Medium Severity

Passing --checkpoint-id with an empty value skips the checkpoint deploy path and the no-argument help exit, then hits assert model_id is not None. That assertion is not caught as APIError, so the CLI can crash instead of showing a clear validation error.

Additional Locations (1)

• packages/prime/src/prime_cli/commands/deployments.py#L198-L201

 

^{Reviewed by Cursor Bugbot for commit 13d3303. Configure here.}