Approval-Bound Actions and Evidence-Gated Commits in Persistent Web-Agent Workspaces

Web agents ground an intent into an interface target at one moment and execute it later, after user approval or multi-step reasoning. Interfaces mutate during that interval, and dispatch and external effect can diverge. We describe a runtime discipline implemented in an Electron/Chromium workspace: server-held, single-use, expiring records bind execution to an approved plan; content fingerprints re-resolve its target against the live interface without selector fallback; and a post-dispatch observation must satisfy an effect contract before a positive receipt is recorded. Inconclusive contract evaluation yields an indeterminate outcome and no automatic re-execution. We explicitly distinguish contract satisfaction from task success: the current contract detects absence of a previously observed baseline under a URL constraint, which does not prove the intended effect or its causal connection to the action. Preliminary conformance evidence comprises 184 kernel dispatches, a separate 45-check workspace gate, and an independent fixture-side oracle for one successful end-to-end trial. We report their separate scopes and propose a controlled comparison of approval binding, target re-resolution, and commit-time verification under interface drift.