Spec Kit + Copilot Cloud Agent: How Do You Progress Beyond “Specify”?

[MrHinsh]

I’ve been using Spec Kit and like the local workflow, but I’m unclear on how that maps to the GitHub Copilot cloud agent workflow.

With Copilot cloud agent, I can select one custom agent when I start the task, but I do not see a way to switch agents later in the same pull request or session. GitHub’s documentation describes choosing an agent when starting the task, and describes custom agents as maintaining their configuration for that workflow. I have not found documentation for changing agents mid-run on GitHub.com.

That leaves me unsure how to apply the normal Spec Kit progression of specify → plan → implement when using the cloud agent. Spec Kit clearly presents the broader workflow as constitution → specify → plan → tasks → implement, including examples that use GitHub Copilot agents, but I have not found clear guidance on how a developer should orchestrate those phases in GitHub’s cloud-agent flow when only one custom agent can be selected at the start.

So my question is:

What is the intended workflow for orchestrating a Spec Kit flow with GitHub Copilot cloud agent?

More specifically:

• If I start with a custom “Specify” agent, how am I supposed to move to planning and then implementation?
• Is the expected pattern to use separate cloud-agent runs for each phase?
• Should I create a single custom agent that knows how to drive the full Spec Kit workflow instead of trying to switch between specialised agents?
• Is there an officially supported handoff model for GitHub.com cloud-agent workflows, or is that not currently part of the workflow on that surface?

I’m trying to understand the recommended developer workflow for using Spec Kit with GitHub Copilot cloud agent in a way that is equivalent to the local phased workflow, but within the practical constraint that the cloud agent appears to be fixed once the task has started. My current reading is that GitHub supports selecting a custom agent at the beginning of a task, and while some documentation mentions a handoffs property in Xcode agent configuration, I have not found equivalent GitHub.com guidance showing agent switching during a single PR workflow.

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I feel like the workflow would need to be:

1. Specify (local)
2. Plan (local)
3. Implementation (cloud)

But the hand off to the cloud creates a new PR for the bracnh that is the spec branch?

[mnriem]

Can you provide a bit more detail on what you are doing?

[MrHinsh]

I want to do a similar workflow tha tI would sue locally, but on the Github Copiklot Cloud agent. Once the agent has been started there is no way to "change" the agent mid PR.

What is the workflow for a developer to orcastrate the SpecKit flow using Github Copiklot Cloud agent.

I updated the question to try and clarify.