dsh-down-payment: Down Payment Calculation

DeepSeek Harness (DSH) has released the dsh-down-payment plugin for efficiently handling deterministic local logic such as financial down-payment calculations. The plugin is implemented in pure Node.js without network dependencies, supports precise calculation based on parameters, and returns detailed results. Users can install it using the specified command and invoke its registered tool within a session. Because the plugin runs inside a local DSH process, users are advised to review the source code and license before use. It is released under the MIT License and suits scenarios that require direct down-payment calculations within agent conversations.