[anycodes]

Description

Process-start acknowledgement can precede application readiness. Public a2 rejected the first nonzero ready_cmd result even though the same owned process and port became healthy within readiness_timeout. Poll only nonzero ProcessResult values inside one monotonic ready-command budget, constrain each probe by the remaining time and preserve cancellation/error cleanup. Creation and startup are never replayed. Prepare the lockstep 0.4.0a3 pair without changing published a2 artifacts.

Refs #121
Refs Alibaba-Agent-Sandbox/awesome-providers#40

Type of Change

• Bug fix
• Tests
• Documentation

Testing

• Public a2 real causal reproduction: initial connection refusal, exact server PID alive, same port healthy inside the budget; original failed result still rejected. Independent typed NotFound cleanup. An earlier diagnostic's false process-list assertion remains recorded.
• Candidate real prepared sandbox: delayed success after five failed probes, a one-second failure deadline, and cancellation. All three owned sandboxes independently typed NotFound.
• Full existing OpenSandbox T4 run 40208641347: all 18 steps SUCCESS, including default/portable/proxy startup, CLI/Python/Node application calls and no-owned-container check. This installed the exact candidate source pair, not public a3; guest runtime remained public a2.
• 25 focused tests and full client suite (2,275 passed, 26 skips) passed. Lint, format, both mypy runs, four distribution builds, clean combined-wheel installation, pip check, hygiene and repository health passed.
• Local server suite: 877 passed, three failures. Raw HTTP fixtures returned 501/502 instead of expected 400; the new uv environment initially lacked pip, and that package-list test passed after normal pip installation. Original failures remain recorded; no assertion was weakened. Latest-head hosted matrix remains the final gate.
• Independent peer and root reviews of runtime/tests found no blocker. Latest follow-up changes only evidence.

Definition of Done

• Regression tests added and passing
• Targeted real-cloud E2E with independent cleanup
• Exact candidate OpenSandbox T4
• Proposed owner record, bilingual docs, changelog
• Versions and dependency kept in lockstep
• Final latest-head CI
• Final independent review, normal merge and publication/readback

The budget covers ready_cmd probes; existing startup-acknowledgement and per-service health budgets are unchanged. No new user option, provider capability, compatibility alias or launch mode. This draft does not claim public a3 or whole-catalog acceptance.