name	cobalt-new-checkout
description	Guides the agent through setting up a new checkout of the Cobalt repository. Use when cloning and building Cobalt for the first time in a new workspace.

Skill: Cobalt New Checkout Setup

Orchestrates environment analysis, workspace validation, persistent state recording, and post-checks execution across checked out working directories.

Workspace Architecture Topology

Projects operating through gclient need structured directory bounds:

workspace/
  ├── .gclient                    <- Declarative dependencies configuration
  ├── .setup_checkpoints.json     <- Persistent execution checkpoints state
  ├── tools/
  │   └── depot_tools/            <- Native chromium build utilities
  └── src/                        <- Repository checkout root
      └── .agent/
          └── skills/
              └── cobalt-new-checkout/
                  └── scripts/
                      └── cobalt_new_checkout.py  <- Setup automation orchestrator

[!IMPORTANT] Script logic executes mutations inside the directory enclosing the src/ project code root. Verify runtime constraints allow write tasks inside matching paths.

Sequential Execution Milestones

AI Assistants run actions by completing 5 primary configuration milestones:

graph TD
    P1[Phase I: Runtime Environment Check] --> P2[Phase II: Depot Tools Bootstrap]
    P2 --> P3[Phase III: Git Identity Verification]
    P3 --> P4[Phase IV: System Sync & Configuration]
    P4 --> P5[Phase V: Validation Post-Checks]

Phase I: Verification of Prerequisite Runtime Context

Validate execution dependencies and script parameters:

Ensure python3 availability.
Check project repository root holds initialized .git state tracking.
Check required arguments inside non-interactive executions (like --github-user).

Phase II: Depot Tools Initialization & Installation

Establish Chromium infrastructure components:

Confirm presence of tools/depot_tools sibling directory.
Inject target path into session environment parameters.
Perform confirmation test by calling validation check commands (gclient --version).

Phase III: Repository Fork Binding & Connection Validation

Verify connection accessibility (e.g. using git ls-remote).
Configure Git tracking endpoints: _gclient and remote fork.

Phase IV: External Engine Sync & Local Configurations

Execute heavy infrastructure synchronization workflows:

Trigger gclient sync tasks.
Write configuration matrices to local .gclient setup.
Run build setup transformations (cobalt/build/gn.py).

Phase V: Verification & System Post-Check Steps

Confirm stability metrics on completed compilation workspace environments:

Validate static lint configurations execution via pre-commit.
Verify source build tasks compile.

Operational Modes

Programmatic / Non-Interactive Operation (Recommended)

python3 .agent/skills/cobalt-new-checkout/scripts/cobalt_new_checkout.py --non-interactive --internal --github-user "<github_user>"

Options:

--non-interactive: Restricts prompt logic blocking from execution.
--internal / --no-internal: Specifies access configurations matching workspace context.
--github-user: Fork integration target parameter.
--reset-checkpoints: Drops tracking status markers to perform clean runs.

Standalone User Interaction

python3 .agent/skills/cobalt-new-checkout/scripts/cobalt_new_checkout.py

Recovery Strategies

System milestones persist to storage file .setup_checkpoints.json. In the event of underlying platform failure conditions:

Study generated exception output diagnostics.
Correct environmental faults.
Re-run setup orchestrations. The system begins tasks at the broken checkpoint.

name	cobalt-new-checkout
description	Guides the agent through setting up a new checkout of the Cobalt repository. Use when cloning and building Cobalt for the first time in a new workspace.