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Evidence record / agent-zero

A dated record of one change, kept so the writing that cites it can be checked. Compiled from the sources listed below by the research run, not written for reading. The judgment lives in the issues that cite it, below.

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

Profile citations

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

Versioned source: run artifact