Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, and the description adds meaningful context about what 'verified' means: skills passed safety checks against command shadowing, injection, concealment, and unsafe scripts. This goes beyond the structured hints and helps an agent understand the trustworthiness semantics of results.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three sentences with no wasted words: the core action is front-loaded, the safety-check detail is relevant, and the get_skill routing is useful. Slightly longer than strictly necessary, but each sentence earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a simple read-only search tool with two optional parameters and an output schema, the description covers what the tool searches, the optional plugin filter, the safety guarantee, and the follow-up tool to retrieve full sources. It does not need to explain return values because an output schema exists.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the input schema already documents both parameters well. The description adds minor context by calling plugin a 'parent plugin' and noting filtering is optional, but it does not substantially improve on the schema descriptions.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description names a specific verb ('Search'), a concrete resource (Sigistry catalog of verified skills), and clarifies what a skill is (SKILL.md instruction sets). It is clearly differentiated from siblings like get_skill (fetch full source) and search_plugins (search plugins rather than skills).

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives actionable routing guidance: use this tool to search the catalog and use get_skill to fetch a match's portable source. It does not explicitly contrast with search_plugins or list_categories, but the intended context is clear enough for an agent to select it for skill discovery.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.