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

With no annotations, the description carries the full burden. It reveals that booth rent is 'quoted directly by shops rather than scraped,' coverage is partial, and the response states how many listings publish a rate. This is valuable behavioral context not available elsewhere. It doesn't mention side effects, but the read-only nature is implied.

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 description is two sentences, front-loaded with the core function and criteria. The second sentence adds a necessary caveat without fluff. No wasted words.

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?

Given no output schema, the description hints at the response by noting it states coverage counts. The tool's purpose, inputs, and key behavioral caveat are covered. It could be slightly more explicit about the output format, but it's complete for a query tool with well-defined parameters.

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%, so the baseline is 3. The description adds context about the meaning of the results (chairs available, booth rent) but does not elaborate on the parameters themselves, which are already well-documented in the schema.

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 clearly states the tool's action: 'Find barbershops and salons ranked by weekly booth rent' with specific criteria (chairs available, Google rating, review count, hiring status). It distinguishes itself from siblings by focusing on shop comparison rather than school or licensee data.

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 provides clear usage context: 'Answers what a chair costs in a given city and which shops have one free.' It doesn't explicitly mention when not to use it or alternatives, but the use cases are well-defined, justifying a 4 rather than 5.

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