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

Annotations already establish readOnly, idempotent, non-destructive and open-world behavior, so the lower bar applies. The description adds a genuine behavioral detail in '(free)' (cost signal) but says nothing about rate limits, auth, or the shape of what comes back beyond 'matching categories and keywords'.

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?

Two short clauses, zero filler, and the primary action ('turn a niche into...') is front-loaded before the rationale. Nothing in the text is redundant with the name or title.

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 single-required-parameter, read-only, no-output-schema tool, the definition covers what it does and roughly what it returns (categories and keywords). Only a hint about output format or how many suggestions to expect is missing, which is minor at this complexity.

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% and the single 'niche' parameter already carries an example ('basement waterproofing'), so the schema does the heavy lifting. The description's word 'niche' adds no format constraints, expected input granularity, or examples beyond what the schema supplies.

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?

Description names a specific verb+resource: it converts a niche into Google business categories and search keywords, and adds an outcome rationale ('helps avoid off-niche results'). This distinguishes it adequately from siblings like find_locations or start_search, though it never names an alternative explicitly.

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?

Usage is only implied — the phrase 'helps avoid off-niche results' suggests it should be used to sharpen a search before searching, but there is no explicit when-to-use, when-not-to-use, or named alternative tool to prefer instead.

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