naming-conventions

Names must communicate ownership, timing, and intent.

C#

Use repository-standard casing and suffixes. Components and systems should be discoverable by type search. Events should state whether they are attempts, pre-change checks, notifications, or completed changes.

Do not introduce an abbreviation that is not established project vocabulary.

A partial class added by a fork should follow the suffix already used for that owner and file family, placed after the semantic suffix: MobStateSystem.Trauma.cs, ActionsSystem.Goob.cs, EnergySwordSystem.Arcane.cs. Before adding a partial, verify that the type can be extended in the same assembly and read the applicable owner and sync rules. Never rename an existing partial to a different fork's suffix or name a new partial after a fork that does not own the code.

Fork-suffixed partials as a conflict tool

Content.Shared, Content.Client, Content.Server, and Content.Common are the conflict surface, because sync brings upstream edits into the same files. A suffixed partial is how a fork adds behavior without editing a base file.

Before editing a base declaration, check whether a partial can carry the change. An owner-suffixed partial can keep additive behavior out of a shared upstream file when the type and assembly support it. Details: .agents/rules/fork-trajectory-priority.md.

Prototypes and resources

Prototype IDs are stable machine identifiers, not display names. Use a feature prefix where collisions are possible. Keep directory names, RSI states, audio collections, map names, and nearby prototypes aligned.

Localization

FTL keys use lowercase kebab-case and a stable owner or feature prefix. Variable names describe meaning, not UI position.

Use stable keys and variables in en-US. Keep them consistent with ru-RU only when Russian localization is explicitly in scope. A module key prefix must make ownership clear. File placement does not protect duplicate keys.

Compatibility

Before renaming a serialized field, prototype ID, map entity, database field, CVar, locale key, or network message, search code, prototypes, maps, migrations, config, the affected locale, and downstream references; include Russian files only when Russian is in scope. Provide a migration or compatibility alias where required.

Verification commands

git grep -n "OLD_NAME" -- path/to/relevant/code path/to/relevant/resources path/to/relevant/config
git grep -n "NEW_NAME" -- path/to/relevant/code path/to/relevant/resources path/to/relevant/config
dotnet build path/to/affected-project.csproj --no-restore
git diff --check

Search all references only when the renamed identifier is a public compatibility surface or the task requires finding every reference. For prototype or locale changes, use a targeted validator when available; follow root AGENTS.md for verification scope instead of automatically running a Release build or global YAML linter.