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Version: 0.1.30

Guide: Building CLI apps

X07 is intended to make it easy for agents to build robust command-line tools.

Canonical (x07 init + x07 run)​

  1. Start from the CLI template (recommended):

    x07 init --template cli

  2. Keep business logic pure and isolate I/O behind adapters so it’s easy to test.

  3. Run via the single front door:

    # OS CLI run (argv_v1 is derived from args after --):
    x07 run -- tool --help

    # Policy-enforced run:
    x07 run --profile sandbox -- tool --help

  4. Distribute a normal CLI binary (no toolchain required at runtime):

    x07 bundle --out dist/tool
    ./dist/tool --help

    For policy-enforced distribution:

    x07 bundle --profile sandbox --out dist/tool

Using ext-cli​

ext-cli parses a declarative CLI spec plus an argv_v1 byte encoding.

If you didn’t start from x07 init --template cli, add the canonical CLI packages from the capability map (see Agent contracts) and then sync the lockfile:

# Pick NAME@VERSION from /agent/latest/catalog/capabilities.json.
x07 pkg add NAME@VERSION --sync

argv_v1 encoding:

  • u32_le(argc)
  • then argc tokens of:
    • u32_le(len)
    • len raw bytes

When running under x07 run, you can either:

  • pass process args after -- (recommended; x07 run encodes argv_v1 into input bytes), or
  • provide argv_v1 bytes directly via --input (advanced).

Canonical execution for CLI args: x07 run -- <args...>​

If your program expects argv_v1, pass process args after -- and x07 run will encode them into input bytes automatically:

x07 run -- tool --help
x07 run --profile sandbox -- tool --url https://example.com --depth 2 --out out/results.txt

This eliminates the need to manually construct --input bytes for normal runs. --input remains available for advanced usage.

See also: docs/examples/agent-gate/cli-ext-cli in the x07 repo (CI-gated reference project).

Using ext-cli-ux​

ext-cli-ux provides deterministic CLI output helpers pinned by arch/cli/:

  • std.cli.profile.from_arch_v1(profile_id) (profile config)
  • std.cli.progress.render_v1(profile, done, total) (pure progress line)
  • std.cli.table.render_v1(profile, rows_doc) (pure table rendering)
  • std.cli.jsonl.encode_v1(doc) (pure JSONL encoding; canonical JSON per line)

For most projects, add the canonical package via the capability map (cli.ux) and sync the lockfile:

# Pick NAME@VERSION from /agent/latest/catalog/capabilities.json.
x07 pkg add NAME@VERSION --sync
  • myapp.cli — CLI spec + parsing
  • myapp.core — pure logic
  • myapp.adapters — OS I/O (fs/net/db)
  • myapp.main — thin wiring

Testing​

  • Unit tests: x07 test --manifest tests/tests.json
  • Integration smoke tests: x07 run --profile sandbox -- ... in CI (assert on the runner report)

Expert (manual inputs + troubleshooting)​

  • Prefer x07 run -- <args...> for normal runs; use --input only when you already have pre-encoded argv_v1 bytes.
  • If x07 bundle output behaves differently than x07 run, check whether you’re relying on an implicit OS capability that should be expressed as an explicit policy.