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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the description complements them by stating that it returns top matches with location, rating, reviews, and profile link. It does not contradict annotations and adds useful context about the return format, but does not describe pagination or further side effects, which is acceptable given the read-only nature.

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 well-structured and efficient: it states the resource, lists filters, specifies returns, then provides a dedicated WHEN TO USE section with alternatives. Every sentence earns its place, and the core purpose is front-loaded. It is longer than minimal but every part adds value.

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 correctly explains the return fields (location, rating, reviews, profile link). It covers the primary use case with examples, clearly routes to siblings, and handles the 7 optional parameters adequately without requiring extra details like pagination. Nothing critical is missing for an agent to call 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 coverage is 100%, so all seven parameters are individually documented in the input schema. The description merely lists the filters (query, service, country, city, industry, min rating) and provides examples like 'Berlin' and 'New York' already present in the schema. It adds no additional semantic meaning beyond what the schema provides, so the baseline 3 is appropriate.

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 states a specific verb+resource: it searches a directory of 47,000+ marketing agencies, lists the available filters, and specifies what it returns (location, rating, reviews, profile link). It also differentiates itself from siblings by naming what it is not (recommendation vs detail).

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 provides a WHEN TO USE section: 'for browsing or filtering ... when the user wants a LIST to explore.' It names the alternatives match_agencies and get_agency with clear conditions (recommendation vs full detail). This leaves nothing to inference.

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