baseline

Deterministic SHA-256 manifests of an emission output tree for regression detection. Used by the CLI flags --capture-baseline PATH and --check-baseline PATH, and consumed by tests/test_baseline.py to pin per-target emission contracts (tests/baselines/<team>-<framework>.json).

The capture skips the full generation pipeline — it walks an existing output tree, hashes every regular file (no symlinks, no excluded path components), and writes a JSON manifest. The diff is per-file SHA equality.

Public Surface

capture(
    root: Path,
    *,
    label: str,
    exclude: frozenset[str] | None = None,
) -> dict[str, Any]

Compute a baseline manifest for root. label is a free-form identifier (e.g. copilot-vscode, bridge-overlay). exclude defaults to caches and VCS metadata. The returned dict has shape {schema_version, label, root, file_count, files: [{path, sha256}, ...]}.

write(manifest: dict[str, Any], out_path: Path) -> None

Write the manifest as deterministic JSON (sorted keys, 2-space indent, trailing newline). Parent dirs created as needed.

load(path: Path) -> dict[str, Any]

Load and parse a baseline manifest from disk.

diff(prior: dict[str, Any], current: dict[str, Any]) -> dict[str, list[str]]

Return {added, removed, changed} — three sorted lists of relative path strings. A file is changed iff present in both with differing SHA-256.

CLI Workflow

# Capture (after a known-good emission)
agentteams --capture-baseline tests/baselines/myteam-copilot-vscode.json \
  --baseline-label copilot-vscode --output .github/agents

# Verify (CI / pre-merge)
agentteams --check-baseline tests/baselines/myteam-copilot-vscode.json \
  --output .github/agents

--check-baseline exits non-zero on any diff and lists added/removed/changed file paths to stderr; --capture-baseline skips the normal generation pipeline.

Notes

• Hashing skips symlinks (no realpath follow).
• Excluded path components (default: __pycache__, .git, .pytest_cache, .mypy_cache, .ruff_cache, node_modules, .DS_Store) are skipped at any depth.
• The manifest's root is recorded as an absolute POSIX path — useful for forensics, not for portable diffing. Per-file path entries are root-relative.

See also

• drift — the template→artifact drift scan (a related but distinct regression signal).
• Update lifecycle guide — where baseline capture/check fits into the update flow.