What problem does it solve? Voice agent teams struggle to turn a failure signal — a bad production call or a failing eval run — into a verified fix without accidentally editing production or overfitting prompts to one transcript. This Skill closes that loop: it reproduces the failure in Cekura simulation first, then iterates edits against a non-production target with attestation and regression checks. ## Core Features & Use Cases - Must-fail-first reproduction: Builds a simulation harness from real call traces and requires a recorded failing Cekura result (repro.json) before any edit is proposed. - Capability-manifest framework: Models where agent config actually lives — repo files, databases, prompt registries, or provider dashboards (VAPI, Retell, ElevenLabs, Bland) — via a per-project .cekura/selfimprove.yaml declaring read/render/apply/deploy/verify mechanics. - Verified improvement loop: Proposes scoped edits, deploys to a sandbox, attests live runtime matches intent, verifies with stochastic pass thresholds, and gates against overfitting before an explicit, rollback-ready production promotion. - Use Case: A production call shows the agent hanging up early. The skill fetches the failure with ended_reason signals, reproduces it in simulation, fixes the prompt on a cloned agent, verifies 7/8 passes, runs a regression sweep, and hands you a validated diff for promotion. ## Quick Start Ask the assistant to fix my voice agent from the failing Cekura result ID 123456 using the self-improving agent workflow.