Decision: Ask for a directory on natural-language init

Status: implemented Implemented: 2026-09-30

Problem

abx init "DESCRIPTION" has only one positional, and that positional is the description, so there is no way to pass a directory. The project was always created as ./<name>/ under the current directory. A long generation then left the files somewhere the user had not chosen.

Decision

• On an interactive terminal, natural-language abx init / abx template init asks Directory for the template project before generation. The default is ./<name> (or ./<--name> when --name is set). Enter accepts it.
• Any other answer is the project directory itself, not a parent that grows another <name> subdirectory. ~ is expanded. The directory is validated and not created until the files are copied, so a cancelled run leaves nothing behind.
• A path that is a file, or a directory that already contains Dockerfile, commands.py, or template.yaml, is rejected before generation. --force overwrites.
• --yes, --json, and a non-interactive terminal skip the prompt and keep ./<name>/. The create-path switch to template-only does not ask again; it still writes ./<name>/.
• Scaffold (-t), --from, and --adopt are unchanged: a path token is still a directory, and an omitted path still means ./<name>/ without this prompt.

Alternatives considered

• A second positional (abx init "DESCRIPTION" ./dir) — rejected: the description already occupies the only positional, and a second one is refused so a sentence cannot be mistaken for a path.
• Ask after generation, once the name is known — rejected: the user would wait through the whole run before choosing, which is the delay this prompt is meant to avoid. The default ./<name> stands in for the name that does not exist yet.

Test strategy

• tests/test_cli/test_create_nl.py: Enter keeps ./<name>/, a typed path is the project directory, --yes does not ask, a file and an existing template directory are rejected before generation.

Files changed

• src/agent_sandbox/cli/commands/sandbox.py, src/agent_sandbox/cli/commands/template.py
• docs/{en,zh}/reference/cli-reference.md, docs/{en,zh}/design/cli-design.md, CHANGELOG.md