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

Annotations already declare the mutation and open-world profile, so the description's main contribution is 'It is public as soon as it is saved' — a genuinely non-obvious fact that there is no draft/review state and the change is immediately customer-visible. It leaves out limits on existing links and any auth/verification requirement, so it is good rather than exhaustive.

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 sentences, zero filler, with the core operation first and the visibility caveat second. Every clause carries information the agent did not already have. Nothing is buried or repeated from the schema.

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 5-parameter mutation with no output schema and full annotation coverage, the description covers what is created and the immediacy of the effect, which is what an agent most needs before writing. It is slightly thin on preconditions (verification status, existing-link limits) given this is an open-world, non-idempotent write.

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 baseline is 3, but the description earns an extra point by glossing the placeActionType enum in natural language ('book, order, reserve, shop online') and identifying uri as the destination, letting the agent pick a valid action kind without opening the schema.

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?

Specific verb (Add) plus resource (action link on the GBP listing), with the valid action kinds enumerated inline ('book, order, reserve, shop online…') and the required destination URL named. An agent can distinguish this from update_gbp_action_link and delete_gbp_action_link from the verb alone, though neither sibling is named 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?

There is no statement of when to use this versus update_gbp_action_link, no prerequisite (e.g. listing verification), and no note on how many action links a listing may hold. The only guidance-adjacent content is the visibility warning, which is a consequence rather than a selection rule.

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