Fabro advertised Bash while its three backends implemented three
different contracts: Daytona evaluated commands through `sh`, and
Docker's streaming, stdio, and setup paths used a login shell. Bash-only
syntax silently misbehaved depending on provider and code path, and
login profiles could change PATH and command behavior per image.
Make `bash -c` the enforced interpreter for every command string the
Unix sandbox API accepts, on every production backend and through both
buffered and streaming execution. This selects the interpreter only —
no `errexit`, no `pipefail`, no login mode — so `false | true` still
succeeds and a workflow that wants other semantics writes them into its
own command.
Local resolves `bash` through the worker's PATH (NixOS has no
/bin/bash) and reuses that one executable across all three command
paths. Docker and Daytona require /bin/bash with no `sh` fallback.
Fresh initialization and resume/start now verify Bash through a shared
marker-validating probe before reporting the sandbox usable, so a
missing or non-Bash interpreter fails at the lifecycle boundary with
provider-specific remediation instead of on the first command. The
probe also rejects Bash in POSIX mode, which an image whose `bash` is
really `sh` would otherwise pass.
Sandbox MCP scripts and the detached launch wrapper move under the same
contract; host-side stdio MCP scripts, hooks, and interactive terminals
are separate executors and keep their existing `sh` behavior.
The `shell` tool's name and JSON schema are unchanged across providers;
only its prose now identifies `command` as Bash source.
BREAKING CHANGE: sandbox commands no longer load login-shell profiles,
so environment set in /etc/profile.d/*.sh, ~/.bash_profile, or
nvm/rbenv/sdkman initializers is gone. Move those exports into the
Dockerfile's ENV or the Daytona snapshot image.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
The fallback provider set was always catalog.all_provider_ids(), computed
at every call site and threaded through five layers alongside the catalog
itself. Fold it into Catalog::resolve_selection_with_catalog_fallback and
carry only a catalog_fallback flag through the transform/validate/
materialize entry points.
- materialize_run delegates to resolve_run_model again instead of
re-inlining its provider normalization and selection
- run_preflight derives ready providers from llm_result instead of
taking both, so callers cannot pass inconsistent pairs; the legacy
tests now exercise the production ready-first routing path
- AppState::resolve_llm_client_with_ready_ids replaces three copies of
resolve-then-extract-provider-ids, and ready_llm_provider_ids
delegates to it
- the unreachable "model resolution failed" preflight check becomes an
invariant error where the materialized run is produced
- validate_prepared_manifest_with_vars/_for_preflight share the
ValidateInput construction
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>