Garmin Analysis Skill

Use cycling-health as the command-line interface for Garmin data. The CLI is public and available from https://github.com/baijian/cycling-health.

Principles

• Be environment-neutral. Do not assume a specific home directory, machine path, repository checkout, shell profile, or operating system.
• Prefer cycling-health from PATH. If it is missing, guide the user to install it from the public repository before continuing.
• When command execution is available and cycling-health exists, run cycling-health upgrade --output json once before Garmin status, sync, or analysis commands.
• Prefer JSON output for data collection and analysis. Use text output only when the user explicitly wants CLI-style output.
• Treat Garmin credentials, passwords, MFA codes, OAuth tokens, and exported activity files as sensitive local data.
• Let users type passwords and MFA codes into their terminal or trusted local prompt. Do not ask them to paste secrets into chat.
• Analyze only fields that exist in the CLI output. Do not invent HRV, sleep score, cadence, power, zones, or training conclusions.
• Preserve CLI warnings and data gaps in the answer.
• Collect data in stages. Start with summary/list commands, then request raw payloads, extended splits, or exported files only when the requested conclusion needs them.
• Separate current readiness from durable cycling ability. A poor night can lower today's readiness without proving fitness loss; one strong ride does not establish a long-term ability gain.
• Region selection for data queries follows login state: if neither cn nor global is logged in, prompt the user to log in; if only one is logged in, use that region; if both are logged in and the user did not specify a region, default to cn. When the user explicitly names a region, use it (it must be logged in). Pass the selected region with --region <cn|global>; omitting the flag defaults to cn. CN-to-Global sync requires both cn and global to be logged in.

Read references/cli-workflows.md when you need exact install guidance, commands, JSON fields, or failure handling.