Introduction

The core design philosophy of DeepSeek Harness (DSH) is “everything is a plugin.” When agents execute complex tasks, intermediate steps often require deterministic tools, such as JSON/YAML conversion, SQL dialect migration, regex testing, or JWT decoding.

If prompting a large model directly to handle these needs, it is usually slower, consumes more tokens, and makes it difficult to guarantee fully reproducible results. dsh-devkit was created to solve this problem: it provides a set of lightweight, deterministic operational tools that let agents call them quickly and at low cost during task flows.

Plugin Positioning

This plugin is maintained by mario03690 and is a tool set based on MCP (Model Context Protocol). It contains no locally executed code and communicates with DSH’s MCP client only through a configuration patch. It aims to provide agents with general-purpose capabilities such as JSON/YAML processing, SQL transpilation, text redaction, and QR code generation.

Installation and Enablement

Install it using DSH’s plugin manager:

dsh plugin --profile <your-profile> add github:mario03690/dsh-devkit

After installation, the plugin injects the necessary MCP client configuration into DSH’s Cordis configuration.

Core Tool List

The plugin provides 14 tools, covering common basic operations in agent development:

  • what_can_you_do: Describes a task (in any language) and returns the list of tools that can perform it, along with invocation examples.
  • redact_text: Removes sensitive information from text, including emails, phone numbers, IDs, API keys, JWTs, card numbers, and IP addresses.
  • json_yaml: Bidirectional conversion between JSON and YAML, with automatic input format detection.
  • validate_json: Validates whether text is valid JSON and can check against a specific schema and top-level type.
  • diff_text: Computes text differences and returns added and removed line numbers (based on the longest common subsequence algorithm).
  • jwt_decode: Decodes the Header and Payload of a JWT, converts timestamps into a human-readable format, and calculates the remaining validity period.
  • regex_test: Tests text with a regular expression and returns match positions and capturing groups (named capturing groups supported).
  • transpile_sql: Converts SQL statements between dialects, supporting MySQL, PostgreSQL, SQLite, TSQL, Oracle, Snowflake, BigQuery, ClickHouse, Doris, StarRocks, and more.
  • make_qr: Generates a QR code PNG from text or a URL.
  • json_format: Validates and formats JSON (2-space indentation); if invalid, it reports the error location.
  • timezone_convert: Converts time zones; supports any IANA time zone (such as Asia/Shanghai) and querying the current time.
  • unit_convert: Converts units, covering length, weight, temperature, area, volume, speed, and data size.
  • sql_from_description: Generates a directly executable SQL file from a natural-language description and table schema.
  • screenshot_url: Captures a full-page screenshot of a specified URL and generates a PNG image.

Typical Usage

Agents can call these tools to complete specific tasks:
* SQL transpilation: Convert a MySQL query into PostgreSQL syntax.
* Sensitive information handling: Extract and remove emails, phone numbers, and API keys from a long piece of text.
* QR code generation: Convert arbitrary text or a URL into a QR code image.
* Time handling: Convert time in UTC+8 to New York time.
* Screenshots: Capture a complete screenshot of a specified web page.

Cost and Privacy

  • Billing: Most tools cost $0.001 per call. sql_from_description costs $0.01 per call, and screenshot_url costs $0.003 per call. Failed calls are not charged.
  • Data retention: Documents and prompts are processed in memory only and are not stored or persisted.
  • Authorization: The free quota can be used without any credentials. An optional AllRouter Key is only passed in request headers and is not stored.

Compatibility and Runtime Environment

  • Runtime: Requires dsh v0.1 developer preview (Cordis v4). Only depends on @deepseek-ai/dsh-mcp-client.
  • Local execution: None. The plugin contains no tool code, does not build local binaries, and includes no lifecycle scripts.
  • File system: No access.
  • Shell/processes: No access.
  • Network access: Only outbound HTTPS to ainetcafe.com is allowed.

Summary

dsh-devkit is suitable for scenarios that need format conversion, text processing, SQL operations, or screenshot capabilities in an agent workflow. It solves the limitations of local execution through server-side operations, while maintaining very high determinism and low cost.

For more information, visit the plugin directory or the GitHub repository.