## Summary
Replacing `BUZZ_ACP_AGENT_COMMAND` with a sandbox launcher hides the
real adapter from Buzz: for example, Goose loses its default `acp`
argument. Add optional `BUZZ_ACP_LAUNCH_PREFIX`, a JSON argument array
applied at the shared subprocess boundary, after normal worker
configuration.
On Unix, every spawn runs `prefix... worker args...` without shell
interpolation. Worker identity, environment setup, stdio and existing
process cleanup are preserved. Invalid or unavailable prefixes fail
launch without falling back to the worker; unset keeps direct launch on
every platform. Configured prefixes fail closed on non-Unix because
per-worker process-tree cleanup is unavailable. Desktop reserves the key
against saved user-environment overrides, and spawn failures name the
executable.
### Related issue
Prerequisite for [Buzz-App
#415](https://github.com/block/buzz-app/pull/415). One commit directly
on `main`, independent of #7942–#7944. No duplicate launch-prefix PR
found. Policy enforcement, verified launcher staging, protected paths
and the supporting runtime pin remain Buzz-App/plugin work.
### Testing
- Original head `9ae9d82f8`: complete ACP suite (990 passed, three
existing ignored), shipped local-task test, real-Goose probe, and full
repository-wide `just ci` passed.
- Review fixes: five launch tests and 44 Desktop environment-filter
tests pass locally, covering the real production platform gate, save
rejection, both merge layers, case variants, and executable error
context.
- Subprocess tests cover direct/wrapped argument defaults, Pi skills,
Hermes/Codex environment, adapter identity, repeated spawns and
invalid/missing prefix refusal.
- Shipped `buzz-acp run` entrypoint completes a task through the wrapper
and deterministic ACP peer.
- Real Goose 1.52.0: direct and wrapped `auth-methods` return identical
results; the wrapper receives `goose acp` with initially empty worker
args.
- Independent agent review: no blocking findings.
- Required push checks passed on the updated head. The existing native
Windows CI job now explicitly runs the platform-contract tests. Its
result is pending; the non-Unix refusal branch was not exercised on this
macOS host.
Repeated-spawn coverage is not a full lazy-pool wake/crash test.
Protected Goose in the Buzz-App UI and human acceptance remain pending.
To try the hook after building `buzz-acp`, use an installed Goose path:
```sh
BUZZ_ACP_LAUNCH_PREFIX='["/usr/bin/env"]' target/debug/buzz-acp auth-methods \
--agent-command /absolute/path/to/goose --agent-args '' --json
```
Expect the same authentication methods as without the prefix. Changing
the prefix to `["/missing-launcher"]` must fail. Draft pending human
testing.
Signed-off-by: Alex Rosenzweig <arosenzweig@squareup.com>
🤖
## Summary
Scripts, scheduled jobs, and other automation need to give an agent one
prepared task and wait for a result without starting a long-running chat
listener. This adds `buzz-acp run`: it reads a task from a local file or
stdin, runs one fresh agent session with the configured tools and
instructions, cleans up, and exits with a machine-readable status.
```sh
buzz-acp run --task ./task.json
cat task.json | buzz-acp run --task -
```
- The versioned JSON task specifies a task ID, intended agent public
key, prepared prompt, and execution time limit. Invalid input or an
identity mismatch is rejected before agent launch. Credentials,
executable, tools, and permissions remain controlled by trusted launch
settings, not the task document.
- Each invocation uses the normal agent equipment: base/persona/team
instructions, enabled memory, tools, model and effort settings,
permissions, and Git identity, credentials, and signing. Both task and
conversational modes obtain these capabilities from one shared runtime
owner; new shared setup belongs there rather than in separate entry
points.
- Launch configuration reads have a separate ten-second bound and can be
cancelled even when a prompt file blocks. A deadline covers adapter
startup through the task turn. Interrupts and termination signals
trigger bounded cleanup. Stdout contains one terminal JSON record;
diagnostics stay on stderr. A normal turn ending is not proof that the
task achieved its goal.
- Normal invocation remains the conversational service. Task mode does
not start chat subscriptions, presence, heartbeat turns, or a persistent
agent pool. Tasks are trusted executable instructions, not sandboxed
input. Reusing a task ID does not prevent duplicate execution, and
uncertain outcomes must not be blindly retried.
See [the task contract](crates/buzz-acp/TASKS.md) for the document
format, exit codes, limits, and examples. URL retrieval, a task server,
and a persistent execution ledger are outside this change.
### Related issue
None found in the existing issue and PR search.
### Testing
- At `4e86bbc97`: 964 unit tests and 22 integration tests passed, with
three existing ignored tests. The package suite ran serially with
inherited harness/Git options cleared. A final test-only shutdown-result
assertion was then checked with the focused memory test and all-target
Clippy.
- All eight real-binary task tests independently passed on the exact
candidate, including blocked configuration reads, file/stdin validation,
session equipment, deadlines, cancellation, and cleanup. The memory test
passed 20 repeated runs. Removing the oversized-input guard fails the
new error assertion; restoring it passes.
- Package all-target Clippy, formatting, file-size checks, and pre-push
Rust/Tauri checks passed. All executed hosted checks passed on the
updated head (54 successful, 28 skipped). The separate Codex review
comment still requests authorization for this exact range.
- Earlier revisions passed the release build and a real Goose 1.51.0
tool-use smoke test. No new release artifact or installed Janet runtime
is claimed for this feedback revision.
- Repository-wide `just ci` was previously attempted; workspace Clippy
passed, then the desktop dependency check stopped on a local pnpm fetch
failure. Hosted checks cover the applicable PR lanes.
---------
Signed-off-by: Logan Johnson <loganj@squareup.com>
Co-authored-by: Larry <627498bd4bd1f281a16431e3c6cce3b5c25b6692798c78672298aefbf2f8f8b5@buzz.block.builderlab.xyz>
