[fas89]

fluid bundle without --out (or with --out -) did not do what its --help says on a contract with a fragments/ directory beside it, the layout fluid split leaves. Found while re-checking drafts 21-29; the fix direction is a founder decision (2026-10-29): follow --help.

What changed

On such a layout fluid bundle wrote contract.bundled.fluid.yaml instead of stdout: fluid bundle contract.fluid.yaml | ... received nothing, --format json put JSON under the .yaml name, and --format tgz put the gzip tarball there, which the next stage read as YAML ('utf-8' codec can't decode byte 0x8b) and --sign / --attest refused (signing_bundle_wrong_format). fluid ship bundles that way on every run. The auto-detect is gone: yaml and json go to stdout and a tgz to <contract id>.fluid.bundle.tgz, the same for every contract (kustomize build and helm template print to stdout the same way). --help names both defaults; the CHANGELOG has a Changed entry and an Upgrade note (a script that read contract.bundled.fluid.yaml passes --out).

From the security review: the default tgz path now gets the validate_cli_path write check an explicit --out gets, so a symlink planted at that name cannot point the write at a forbidden path.

Borrow before build

Bug fix inside existing code; precedent for "no --out means stdout": kustomize build, helm template, and fluid itself (- means stdout in odps.py).

Validation

• Full suite (-n 6 --dist loadscope --ignore=tests/perf): 30434 passed; the 7 failures and 2 collection errors fail identically on clean main (dlt credential-field drift, the DuckDB sandbox broad-root tests, the live claude CLI test, two CI-only modules); one MCP test that failed under load passes alone on the branch and on main. After the last commit: tests/forge + the bundle, signing, attestation, fragments-bundle, compat-gate and security tests, 1000 passed.
• ruff, black 24.10.0, import-linter 6/6, mypy --strict hotspots, product guardrail, detect-secrets: green.
• New tests fail on main (3 of the fragment-layout tests; the symlink test).
• Live, on a fragment layout: fluid bundle contract.fluid.yaml | head prints the composed contract; --format json pipes into a JSON parser; --format tgz writes commerce.orders_events.fluid.bundle.tgz (gzip), no contract.bundled.fluid.yaml.

Reviews

• /security-review: PASS. Two LOWs, both pre-existing: the default tgz path skipped the --out write check (fixed here), and the stdout-mode logging swap adds a stderr handler without the redaction filter (follow-up).
• /world-class-inspection: PASS (codebase, tests, docs, consistency); P3 notes fixed (the JSON test oracle, CHANGELOG precision).
• /defect-scan: no confirmed defect in touched code. Every caller checked: fluid ship (now leaves <id>.fluid.bundle.tgz, as on flat layouts), engine.bundle(), generated CI (explicit --out), MCP/IDE/templates (no calls).

Follow-ups (pre-existing, not this change)

• The stdout-mode log swap (bundle.py ~349-357) skips the secret-redaction filter on its new stderr handler and prints some events twice.
• An id longer than ~238 characters makes the default tgz name too long (also on flat layouts).
• Stale hints: fluid forge suggests fluid bundle --check (not a flag) and cat contract.bundled.yaml.

Documentation

• Docs PR linked
• No docs needed
• Docs TODO — forge_docs docs/cli/bundle.md ("Default output location" table and the tgz warning), docs/cli/ship.md, docs/cli/split.md, docs/concepts/fragments.md: comes with the forge_docs pages PR of this wave.