creating-a-commit

name	creating-a-commit
description	Use when creating git commits, staging changes, or writing commit messages - defines commit format rules, conventional commits usage, ticket-branch handling, and AI attribution requirements

Creating a Commit

Format Selection

Check the current branch name to decide which header format to use:

digraph format_selection {
    "Branch name?" [shape=diamond];
    "Ticket format\n<ticket>: <description>" [shape=box];
    "Conventional format\n<type>[scope]: <description>" [shape=box];

    "Branch name?" -> "Ticket format\n<ticket>: <description>" [label="matches ticket pattern\ne.g. MPCC-1234"];
    "Branch name?" -> "Conventional format\n<type>[scope]: <description>" [label="anything else"];
}

Ticket Branches

When the branch name matches a ticket pattern (e.g. MPCC-1234, MPMX-42), the ticket replaces the type prefix:

<ticket>: <description>

[optional body]

Assisted-by: <model name> via <tool name>

Non-Ticket Branches

When the branch does not match a ticket pattern, use Conventional Commits:

<type>[optional scope]: <description>

[optional body]

Assisted-by: <model name> via <tool name>

Types: feat, fix, build, chore, ci, docs, style, refactor, perf, test

• feat — new feature (correlates with SemVer MINOR)
• fix — bug fix (correlates with SemVer PATCH)
• Append ! after type/scope for breaking changes (correlates with SemVer MAJOR)
• A scope MAY be provided in parentheses: fix(parser): handle empty input

Header Rules

These apply to both formats:

• Maximum length: 72 characters
• Imperative mood ("add feature" not "added feature")
• Do NOT end with a period
• Do NOT capitalise the first letter of the description

Casing

The entire commit message MUST be lowercase. Exceptions:

• Proper nouns with inherent casing (e.g. NixOS, GitHub, OpenCode)
• The Assisted-by trailer key (standard git trailer convention)
• Model and tool names in the Assisted-by value (e.g. Claude Opus 4)

Body

Optional. Describe the why, not the what. May use prose or bullet points. Must be separated from the header by a blank line.

AI Attribution (Assisted-by Trailer)

Mandatory on every commit an AI agent creates, including trivial ones.

Per Xe Iaso's convention and Fedora's AI-Assisted Contributions Policy.

Rules

1. Use the actual model name you are running as — do NOT fabricate.
2. Use OpenCode as the tool name (all agents in this repo run inside OpenCode).
3. Multiple models = multiple Assisted-by lines.
4. Must be the last line(s) of the commit message.

Examples

Ticket branch

MPCC-34: add opencode global agent rules

add programs.opencode.rules with conventional commit enforcement,
lowercase policy, and assisted-by trailer requirement so all ai
agents produce consistent, machine-readable commit messages.

Assisted-by: Claude Opus 4 via OpenCode

Non-ticket branch (feature)

feat(opencode): add skill for commit message formatting

Assisted-by: Claude Sonnet 4 via OpenCode

Non-ticket branch (fix)

fix: resolve grafana service breakage after upgrade

the grafana module changed its systemd unit name in the latest
nixpkgs update, breaking the existing service override.

Assisted-by: GPT-4o via OpenCode

Non-ticket branch (chore, no body)

chore: update flake lock

Assisted-by: Claude Opus 4 via OpenCode