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

Annotations already cover readOnly, idempotent, and non-destructive, so the bar is lower. The description adds genuine context beyond them: only already-published posts are returned and results are ordered newest first. The closing 'read-only and cannot delete posts' clause largely restates the annotations, but the published-filter and ordering are real additions.

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, front-loaded with the scope before the return-value detail. The return-value sentence overlaps with the output schema, which slightly dilutes the otherwise efficient structure.

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?

With an output schema present, the description needn't enumerate return fields, and it adequately covers operation, scope, and ordering for a simple list tool. The only meaningful gap is parameter documentation (limit), which the description leaves to the schema.

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% across two params. The description hints at the required 'location' via 'one owned location' but never explains the 'limit' parameter (default 20) or pagination behavior, so it fails to compensate for the schema gap.

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 (Lists) plus resource (Google Business Profile posts) with narrowing scope: already-published, for one owned location, newest first. This cleanly distinguishes it from gbp_create_post and gbp_update_post siblings without needing to name them.

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 'for one owned location' note implies context but gives no explicit when-to-use/when-not guidance or alternative routing (e.g., toward gbp_create_post for drafts or gbp_update_post). Usage is inferable from the verb but not stated.

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