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Finding / agent-zero

2026-10-13-agent-zero-nonblocking-terminal-i-o-and-complete-ssh-sends-reduce-concurrent-stalls

Nonblocking terminal I/O and complete SSH sends reduce concurrent stalls. POSIX PTY reads now use nonblocking descriptors and writes buffer partial bytes cooperatively, so a full terminal or stale readiness event does not block the shared loop in the old way. An incomplete cancelled POSIX send discards its shell; a fully drained send retains state. SSH uses sendall through asyncio.to_thread instead of ignoring Channel.send’s partial-send count. Cancelling an in-flight SSH send closes that connection and intentionally discards its shell state, preventing partial input from contaminating later commands.

Channel: tagged-release. Half: both. Date: 2026-10-13 (first stable; commits entered history 2026-10-06).

Operator consequence: Re-test concurrent shell jobs and long heredocs on v2.14. Expect interrupted SSH sends to lose shell state; restart dependent work deliberately. The mechanism supports improved concurrency and command integrity, not a guarantee that every browser or terminal hang is fixed.

Receipt

Finding metadata

Confidence
high

Run: 2026-10-13-profile-refresh-2026-09-21_2026-10-13-frontier-v0

Finding ID: 2026-10-13-agent-zero-nonblocking-terminal-i-o-and-complete-ssh-sends-reduce-concurrent-stalls

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Source links

Primary links, including exact changelog lines when available.

  1. Agent Zero
    commit2026-10-13-agent-zero-nonblocking-terminal-i-o-and-complete-ssh-sends-reduce-concurrent-stallsgithub.com/agent0ai/agent-zero/commit/c58061f0ee05fbc6ad10d6cbe25980b55969b47ccommit2026-10-13-agent-zero-nonblocking-terminal-i-o-and-complete-ssh-sends-reduce-concurrent-stallsgithub.com/agent0ai/agent-zero/commit/ad5bebbea53fc8827ba542364f6bd50e2c04cbfe