Update an existing pet.

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

Annotations provide idempotentHint and openWorldHint, but the description adds no additional behavioral context such as whether this is a full or partial update, authentication requirements, or effects on associated data. It does not leverage the description field to enrich what annotations already convey.

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?

The description is a single concise sentence with no wasted words. It is appropriately sized for delivering the basic idea, though it sacrifices depth for brevity.

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?

Given the tool's complexity (6 parameters, nested objects, no output schema), the description is far too sparse. It does not explain return values, error behavior, or the scope of the update, leaving significant gaps for an agent.

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?

With only 17% schema description coverage, the description should compensate by explaining key parameters. It mentions 'Id' but the schema does not list id as required, and the actual required fields (name, photoUrls) are undocumented. This could lead to incorrect invocation.

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 'Update an existing pet by Id' clearly states the action (update), the resource (pet), and the identifying mechanism (by Id). It is specific enough to distinguish from add_pet or delete_pet, though it does not explicitly differentiate from the sibling update_pet_with_form.

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 guidance on when to use this tool versus alternatives. It does not mention prerequisites, exclusions, or when update_pet_with_form might be preferred. The description simply states the action without any usage context.

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