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Evidence record / temporal-agent-harness

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-temporal-agent-harness-0-5-0-replaces-runner-state-and-authored-run-methods-with-declared-state-and-lifecycle-hoo

0.5.0 replaces runner.state and authored run methods with declared state and lifecycle hooks. Observable state moves from runner.state registration to class-declared agent.state. agent.defn generates the workflow run method and rejects an author-defined run at import; setup/teardown hooks take one-time async work. Required/optional typed initialization is validated before the constructor. Invalid or missing input becomes a non-retryable workflow failure instead of a workflow-task retry loop. Teardown runs after draining close or on cancellation if setup completed, not on failure.

Channel: preview-or-beta (T5 and T6). Half: both. Date: 2026-09-30 (released; implementations 2026-09-25 and 2026-09-29).

Operator consequence: Migrate observable-state declarations, remove the old authored run wrapper and stacked workflow.defn, and move async lifecycle work into agent.setup/agent.teardown. Handle rejected initialization as a terminal start failure. Do not put essential failure cleanup only in teardown. This supplements the message/event migration in section 2; unchanged migrated examples are not alleged to fail.

Receipt

Finding metadata

Confidence
high

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

Finding ID: 2026-10-13-temporal-agent-harness-0-5-0-replaces-runner-state-and-authored-run-methods-with-declared-state-and-lifecycle-hoo

Profile citations

Source links

Primary links, including exact changelog lines when available.

  1. Temporal Agent Harness
    commit2026-10-13-temporal-agent-harness-0-5-0-replaces-runner-state-and-authored-run-methods-with-declared-state-and-lifecycle-hoogithub.com/temporal-community/temporal-agent-harness/commit/c0f8ca01bf550cf1da349b02c84e0ac545c2c1d2commit2026-10-13-temporal-agent-harness-0-5-0-replaces-runner-state-and-authored-run-methods-with-declared-state-and-lifecycle-hoogithub.com/temporal-community/temporal-agent-harness/commit/faec13de3ee346597f179ee8cb9c8e474beeb03btagged commit file2026-10-13-temporal-agent-harness-0-5-0-replaces-runner-state-and-authored-run-methods-with-declared-state-and-lifecycle-hootemporal-community/temporal-agent-harness / temporal_agent_harness/harness/state/decl.py#L105-L116tagged commit file2026-10-13-temporal-agent-harness-0-5-0-replaces-runner-state-and-authored-run-methods-with-declared-state-and-lifecycle-hootemporal-community/temporal-agent-harness / temporal_agent_harness/harness/agent_workflow.py#L993-L1011tagged commit file2026-10-13-temporal-agent-harness-0-5-0-replaces-runner-state-and-authored-run-methods-with-declared-state-and-lifecycle-hootemporal-community/temporal-agent-harness / temporal_agent_harness/harness/agent_workflow.py#L1051-L1095tagged commit file2026-10-13-temporal-agent-harness-0-5-0-replaces-runner-state-and-authored-run-methods-with-declared-state-and-lifecycle-hootemporal-community/temporal-agent-harness / temporal_agent_harness/harness/agent_workflow.py#L1130-L1139tagged commit file2026-10-13-temporal-agent-harness-0-5-0-replaces-runner-state-and-authored-run-methods-with-declared-state-and-lifecycle-hootemporal-community/temporal-agent-harness / temporal_agent_harness/harness/agent_workflow.py#L1216-L1235

Versioned source: run artifact