dsh-mysql

MySQL connector plugin for DeepSeek Harness. Configure multiple MySQL connections in the DSH settings page, switch the active connection per session from a button in the composer, and expose MySQL tools globally to every agent preset — no preset edits required.

中文说明

Features

• Settings page (设置 → MySQL 数据库): add / edit / delete / test connections — host, port, user, password, default database, per-connection table allowlist and write permission (default off).
• Composer button (🐬, left side of the input bar): pick the connection for the current session only; switch any time. The chosen connection and its readable tables are injected into each turn's runtime-context snapshot (appended after the conversation, so switching or editing a connection never rewrites the stable system-prompt prefix used for context caching).
• Global tools (available under every agent preset):

Tool	Purpose
mysql_query	Read-only single-statement SELECT/SHOW/DESCRIBE/EXPLAIN against the selected connection. Table allowlist enforced, multi-statement rejected, MAX_EXECUTION_TIME hint injected into SELECT, max 2000 rows returned with a truncated flag.
mysql_tables	Inspect the schema (columns, types, keys, comments) of the readable tables via information_schema.
mysql_execute	INSERT/UPDATE/DELETE only, and only when the connection has allowWrite enabled (default off). DDL (DROP/TRUNCATE/ALTER/...) and multi-statement SQL are always rejected.

• Per-session selection is resolved through the tool execution context (exec.agent), so the model always queries the database the user picked in the composer.
• All connection state persists locally in $DSH_HOME/storages/dsh-mysql/connections.json; passwords are stored in that file and never sent back to the browser UI (the UI only sees hasPassword).

Install

# From npm / GitHub (recommended once published)
dsh plugin --profile web add github:1321928757/dsh-mysql#v0.1.4

# Or from a local tarball
pnpm pack
dsh plugin --profile web add C:\path\to\dsh-mysql-0.1.4.tgz

Then restart dsh web (make sure the old process really exited). After the restart, open 设置 → MySQL 数据库, add a connection and press 测试连接.

Quick start

1. Open Settings → MySQL 数据库 → + 添加连接; fill in host / port / user / password / default database, optionally list the readable tables (comma separated), decide whether to enable write permission. Press 测试连接, then 保存.
2. In any conversation, click the 🐬 button on the left of the composer and pick a connection (per-session).
3. Ask the agent anything about the database — it can call mysql_tables to inspect the schema and mysql_query to read data. When the connection has write permission enabled, mysql_execute can run INSERT/UPDATE/DELETE.

Safety model

• Tool-layer enforcement, defense in depth. For production use, also create a dedicated MySQL account with only the needed privileges (ideally SELECT only) for the agent.
• mysql_query accepts only single SELECT/SHOW/DESCRIBE/EXPLAIN; mysql_execute accepts only single INSERT/UPDATE/DELETE and requires the per-connection allowWrite flag.
• Table allowlist: when a connection lists tables, every statement is checked and rejected if it references a table outside the list (an empty list means "all tables").
• SELECT statements get a MAX_EXECUTION_TIME(15000) optimizer hint injected; result sets are capped at 2000 rows.
• Passwords live in $DSH_HOME/storages/dsh-mysql/connections.json (plain text on the local machine). Use file permissions / a dedicated OS account to protect it.

Migrating from a preset-embedded mysql tool

If a preset previously embedded mysql_query/mysql_execute (e.g. a row loading a local mysql-tool.mjs):

1. Install this plugin into the profile.
2. Remove the mysql tool row (and connection config) from the preset's agent.cordis.yml; keep the business persona text.
3. Restart dsh web, then recreate the connection in Settings → MySQL 数据库. The tool names are identical, so preset prompts that mention mysql_query keep working unchanged.

Development

node --check lib\index.js lib\shared.js lib\typert.host.js lib\client.js
node test\shared.test.mjs
pnpm pack
dsh plugin --profile web add .\dsh-mysql-0.1.4.tgz
# restart dsh web, then verify in the browser

License

MIT