Struct PackContext 

pub struct PackContext {
    pub cwd: PathBuf,
    pub os: String,
    pub shell: String,
    pub date: String,
    pub headless: bool,
    pub is_git_repo: bool,
    pub model: Option<String>,
    pub os_version: Option<String>,
    pub timezone: Option<String>,
    pub strip_identity: bool,
}

Dynamic, per-run context a pack’s preamble is rendered against.

Deliberately small (like ToolCtx, ADR-0003 rejects god-object contexts): the fields a harness’s real prompt needs (Task 13) — cwd/OS/shell/date + the headless identity branch. Grows only if a ported prompt needs more.

Fields

cwd: PathBuf

Absolute working directory shown to the model.

os: String

Target OS label (e.g. macos).

shell: String

Login shell (e.g. /bin/zsh).

date: String

Current date, preformatted (the preamble stays a pure function of context).

headless: bool

Headless run → autonomous identity branch (vs interactive). See Task 13.

is_git_repo: bool

Whether the working directory is inside a git repository. Rendered in the Claude pack’s # Environment block (Is a git repository: <bool>, D9). Cheaply probed by the exec/tui layer (a .git walk) — no host handle in preamble().

model: Option<String>

The model id/name for the Claude pack’s env “You are powered by the model …” line (D9). None skips the line (the pack does not guess).

os_version: Option<String>

The OS version string for the Claude pack’s env OS Version: line (uname -s -r, computed by the exec/tui layer). None skips the line.

timezone: Option<String>

The IANA timezone name for the codex pack’s <environment_context> <timezone> line (e.g. America/Los_Angeles), resolved best-effort by the exec/tui layer. None omits the line (codex’s field is optional).

strip_identity: bool

Strip identity-revealing sentences from the rendered prompt (e.g. grok’s “You are Grok released by xAI.” and the <user_guide> block naming the Grok Build TUI). Default false = faithful reproduction (user decision, 2026-07-18); true is for A/B runs where the harness’s self-identity would contaminate the comparison. Post-processing on the rendered output only — the verbatim template copies are never edited.

Trait Implementations

impl Clone for PackContext

fn clone(&self) -> PackContext

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for PackContext

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.