cobalt-new-checkout

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.

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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

Register development origins and configure tracking parameters:

• 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.

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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

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Recovery Strategies

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

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