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

Annotations already declare read-only/idempotent/open-world safety, but the description adds non-obvious behavior beyond them: searches are logged to a roadmap database, high-frequency unmet queries jump the build queue, and the call costs no credits. These side-effect and cost disclosures are exactly the kind of context annotations cannot convey.

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?

The actionable instruction is front-loaded and clear, but the bulk of the text is an 81-domain enumeration that is largely redundant for a tool whose purpose is to find those domains. It conveys coverage credibility, so it earns its place somewhat, but it is longer than strictly necessary.

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 discovery tool with no output schema, the description covers everything an agent needs: what it returns ('exact tool names for matched domains'), when to call it, and the follow-up to obtain an API key. Nothing needed to invoke it correctly is missing.

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?

The single 'query' parameter is fully documented in the schema (100% coverage, including examples), so the schema does the heavy lifting. The description reinforces intent with example phrases but adds no syntax or format detail beyond the schema, which is the correct baseline when coverage is complete.

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 role ('guide to LiveDataLink's entire data catalog') and distinguishes itself from the 377 sibling tools by being the discovery/meta entry point. An agent immediately understands this is the catalog-search tool, not a data-fetching tool.

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 call it FIRST when unsure which tool to use or when the user asks about data availability, then lists concrete trigger phrases ('what data do you have?', 'can you look up X?'). It also directs the follow-up step (get_free_api_key or pricing), giving complete routing guidance.

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