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

With no annotations, the description carries the full behavioral burden and mostly does: it discloses the search is semantic/ranked by relevance, that natural-language queries perform best, and exactly which fields come back (ID, name, description, category, price per successful call, latency, endpoints). It omits any note on result limits beyond the parameter default or on cost/rate implications of searching the catalog.

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?

Roughly four sentences, front-loaded with the usage imperative and the core resource, followed by examples and the return contract. The example list is somewhat long but each example maps to a distinct use case and 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 two-parameter read-only search with no output schema, the description supplies everything needed: what it searches, how to phrase queries, when to reach for it first, and the shape of the response. No meaningful gap remains for an agent to invoke it correctly.

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 description coverage is 100% for both parameters, so the schema already documents that query is natural language and limit is max results (default 10). The description reinforces natural-language phrasing with examples but adds no syntax or formatting rules beyond what the schema provides, so baseline 3 applies.

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?

States a specific verb and resource ('Semantic search across ALL 10,000+ public APIs on Zyla API Hub') and scopes it distinctly from browse_catalog/list_categories by emphasizing semantic, natural-language ranking. An agent can tell what it returns (ranked APIs with ID, name, price, latency, endpoints) without opening the schema.

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?

Explicitly says to 'Use this FIRST whenever the user needs live, real-world or external data you do not have' and enumerates trigger domains (weather, prices, stocks, lookups, scraping). It gives clear when-to-use context, but never names a sibling alternative (e.g. browse_catalog) or a when-not-to-use condition.

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