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

Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true and destructiveHint=false, so the safety and idempotency profile is covered. The description's only added context is scope ('across all Craigslist sites'), which is genuinely useful because it signals a federated search rather than a single-site lookup. It says nothing about result volume, pagination, or rate limiting — relevant for an open-world scraping tool.

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?

A single short sentence with the scope stated first and no filler. It is efficient, though the unsubstantiated 'filtering by categories' clause is the one phrase that does not pay off given the empty schema.

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?

There is no output schema, so the description should carry more weight, yet it never explains how a search is actually expressed — no query term, no location/region, no result shape. For a search tool whose schema is an open object with no defined properties, this leaves the agent guessing at the most important inputs.

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?

With zero declared parameters, the baseline would be 4, but the description promises 'filtering by categories' while the schema exposes no such parameter and only allows arbitrary additional properties. That mismatch means the one filtering hint cannot be reliably mapped to an argument, so it adds less meaning than a clean zero-param tool would.

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') and resource ('all Craigslist sites') plus the category-filtering angle, which is enough to distinguish it from the unrelated sibling search tools (datagov_search, education_search, loc_search). It stops short of naming any sibling or contrasting scope with them, so it lands at clear-but-undifferentiated.

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?

There is no guidance on when to use this versus the other search-family siblings, no prerequisites, and no exclusions. The agent is told what it does but not when it is the right choice.

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