## Why
Terminal-Bench can show task correctness while missing Buzz-specific
collaboration failures, such as posting a final answer outside the
user's thread. Add a small Buzz-native suite that scores relay behavior
directly.
## What
- Add Harbor tasks for direct thread replies, event-level callback
mentions to a three-word user identity, targeted reads of explicitly
named paths outside the workspace, and exact temporary-channel
membership against a seeded directory of 50 users and 10 bots
- Export sanitized post-agent relay evidence and extend solo
runtime/provisioning for deterministic verification
- Expose channel TTL in CLI search output and cover positive and
negative transcript/state fixtures
## Risk Assessment
Low to medium — this primarily adds benchmark and testbed machinery. The
CLI change is an additive `ttl_seconds` field in channel-search JSON;
relay behavior is unchanged.
## References
- Motivated by the Buzz-specific behavior observed while benchmarking
https://github.com/block/buzz/pull/6128
- The named-path regression case covers the issue being fixed by
https://github.com/block/buzz/pull/6261
- Local live Sonnet runs: `reply-to-thread`, `user-mention`, and
`create-channel-invite-users` each scored reward 1.0 with zero
exceptions
- The current branch prompt scored 3/5 on a concurrent
`read-named-path-outside-workspace` batch: one explicit
workspace-boundary refusal and one missing final response
Generated with Codex
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Signed-off-by: Salman Mohammed <smohammed@squareup.com>
