When developing agents with DeepSeek Harness (DSH) or DSH Desktop, quickly filtering suitable public APIs is a common requirement. Manually browsing lists is often inefficient and lacks filtering capabilities. The dsh-universe-api plugin provides an offline, deterministic solution.

What It Is

This is an offline API discovery plugin for DeepSeek Harness (DSH) and DSH Desktop. It is maintained by Ruixinhua. It registers a read-only tool named universe_api_search for deterministic searches over a normalized snapshot of the public-apis catalog.

Core Features

The plugin provides the following capabilities:

  • Offline search: Performs offline, deterministic searches across 1,693 normalized public API records.
  • Multilingual support: Supports English and Chinese query expansion, Unicode normalization, and CJK-aware matching.
  • Hard filtering: Applies hard filters for category, authentication, HTTPS, CORS, status, and source tier.
  • Stable ranking: Provides match reasons and catalog freshness metadata for stable ranking.
  • Private catalog: An optional private canonical-v1 catalog can completely replace the bundled snapshot.
  • Unified contract: A single DSH contract that can be reused in the CLI, web profiles, and DSH Desktop.

Installation and Enablement

Run the following command in the DSH Desktop terminal to install:

dsh plugin add github:Ruixinhua/dsh-universe-api#v0.1.2

After changing files or paths, restart DSH Desktop to ensure the new package enters the Loader composition.

Typical Usage

Use the tool directly in a DSH prompt.

Use universe_api_search to find 3 weather APIs that require no API key and have HTTPS=yes and CORS=yes. Explain why each result matched.

Chinese example:

请使用 universe_api_search，找 3 个无需 API key、HTTPS=yes、CORS=yes 的天气 API，并说明匹配理由。

The tool accepts the following input parameters (types and behavior):

Parameter Type and behavior
query Optional natural language string, up to 2,048 characters. Omit this parameter to browse using filters only.
categories Optional string array, up to 20 values, each up to 128 characters. Multiple values use OR semantics.
sourceTier all (default), public, or apilayer.
auth none, api_key, oauth2, basic, bearer, signed, user_agent, other, or unknown.
https, cors yes, no, or unknown; values are matched exactly.
status active, coming_soon, stale, candidate, or unknown.
limit Integer from 1 to 20; default 5.

Use Cases and Notes

  • Nature: This is a discovery tool, not an API client. It never calls candidate APIs, does not accept API keys, and does not perform runtime network requests.
  • Validation: Before making important decisions, be sure to verify pricing, availability, authentication, and terms in the provider’s official documentation.
  • Strict filtering: The plugin does not silently relax filters when there are no matches. In particular, unknown is different from no, and in the bundled catalog containing only public data, sourceTier: "apilayer" returns zero results.

Conclusion

This plugin provides DSH with a reliable offline discovery mechanism. The source code and documentation are located at: https://github.com/Ruixinhua/dsh-universe-api