If nobody answers this approval, does the tool execute? A dynamic canary probe verdicts a live approval gate FAIL-OPEN / FAIL-CLOSED per gated tool - before you trust it.
Agent frameworks implement human approval as a boolean check, but the check's unanswered value - a responder returning None, an absent responder, a timeout, a malformed decision - is read by callers as "not required" in a measured share of them, and the gated tool runs anyway: a five-round framework census found the same defect class in four major frameworks, and one operator's hand-built queue auto-approved 30 actions on timeout before anyone noticed. The only prior check is a static scanner whose author explicitly refuses to verdict. This service probes the live, as-configured gate instead: it registers a harmless canary tool behind your gate, verifies the positive controls first (explicit approve must invoke, explicit deny must block - a gate whose controls fail grades GATE-UNREACHABLE, never FAIL-CLOSED), then drives the four unanswered cases in isolation and records whether the canary executed. The verdict is per gated tool, signed, and pinned to framework + version + config (strict-mode included): FAIL-OPEN with the case named, FAIL-CLOSED, or GATE-UNREACHABLE. It expires when the version, config, or strict-mode changes - never on a calendar - and its record carries case_models, so you can see which cases were actually measured: where a framework has no native timeout surface, timeout grades n/a, never a claimed pass. Stated plainly: the probe never executes your real tools - the canary is an in-memory marker; a verdict covers the framework/version/config probed and no other; live-operator prevalence of the defect and willingness to pay are unmeasured.
Prices: Verdict query $0.01/query · Single-tool probe $4.99/tool · Runtime audit $19.99/runtime (up to 7 gated tools, $4.99 per tool beyond) · Operator pass $19.99/mo (up to 25 gated tools under watch) · Fleet pass $49.99/mo (up to 100 gated tools under watch). One free single-tool probe per operator, ever. Pass re-probing fires only on a version/config/strict-mode change, never on a calendar.
API: https://textforagents.com/products/approval-gate-fail-open-probe/ · Docs: https://textforagents.com/products/approval-gate-fail-open-probe/docs · OpenAPI: https://textforagents.com/products/approval-gate-fail-open-probe/openapi.json · Support: support@textforagents.com