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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and destructiveHint=false, so the safety profile is covered. The description adds value beyond that by explaining the output dependency (the location id other tools need) and warning against guessing ids, though it omits any pagination or multi-account volume notes.

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 tight sentences with the resource and the key caveat front-loaded. Every clause earns its place: what it lists, what it returns, and the ordering/prerequisite rule.

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 zero-parameter read-only listing tool with no output schema, the description supplies everything needed to invoke it correctly: the resource, the prerequisite ordering, and the meaning of the identifier returned. No output schema means return values need not be detailed.

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?

The tool takes no parameters, so there is nothing for the description to disambiguate and the baseline is 4. The mention of gbp_location_id is an output detail, not a parameter, so it neither helps nor hurts this dimension.

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?

States a specific verb and resource: 'List the Google Business Profile locations this sign-in manages'. It also clarifies the return payload's key field (gbp_location_id) and its role for the other gbp_* siblings, so an agent can distinguish it from gbp_posts, gbp_reviews, or highlevel_list_locations without opening a schema.

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?

Provides explicit ordering and a negative constraint: 'Call this first; never guess a location id.' This tells the agent both when to use it (before other gbp_* tools) and what not to do, which is unusually clear routing guidance.

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