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

Annotations already declare readOnlyHint=true and openWorldHint=true. The description adds meaningful behavior beyond that: the rolling window excludes today, the default is 30, metrics defaults to all and is case-insensitive, and the response includes impressions_total plus a lowercase-keyed sum per metric. It doesn't mention rate limits or failure modes, so not a 5.

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?

It is front-loaded with the resource and metric list, then period rules, then metric filtering, then response shape. The long enumeration of metric token names is dense but necessary; overall it earns its place without much waste.

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 6-parameter reporting tool with an output schema, all decision-relevant information is present: period logic, metric filtering, time-series toggle, and workspace scoping. The description even summarizes the response shape despite the output schema existing.

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 0%, but the description fully compensates: days semantics and default, the exact accepted metric names and case-insensitivity, start_date/end_date format and their precedence over days, include_time_series adding a daily series, and workspace being optional for single-workspace cases — essentially all 6 parameters are documented with meaning.

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 resource (Business Profile performance) and enumerates exact metrics returned: impressions split by Maps/Search, calls, website clicks, direction requests, messages, bookings, food orders, and menu clicks. This clearly distinguishes it from siblings like gbp_local_rank, gbp_reviews, and gbp_search_keywords.

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?

It gives precise guidance on the two mutually exclusive period modes: days (rolling window to yesterday, default 30) OR start_date+end_date replacing days, and states workspace is optional when only one workspace exists. It doesn't explicitly contrast with sibling GBP tools, so it falls short of a 5.

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