petstore-api.getPetById

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

The annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the description does not need to restate safety. The description adds minimal behavioral context beyond that, but it is consistent with the annotation and indicates a single-resource lookup rather than a list or mutation operation.

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, front-loaded sentence with no filler. It is appropriately brief for such a simple lookup operation, though the brevity also contributes to missing usage and invocation context.

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?

The annotations and output schema cover the safety profile and return shape, but the empty input schema means the description must compensate for the missing pet ID parameter and does not fully do so. It is enough for basic selection but not strong enough for reliable invocation.

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 input schema has zero declared parameters, so the phrase 'by ID' carries the only parameter-like meaning. It tells the agent the conceptual key is a pet ID, but it does not explain how to supply it, what type it should be, or whether it is required, leaving a meaningful ambiguity in the tool definition.

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 gives a specific verb (find), a clear resource (pet), and the lookup criterion (by ID). This distinguishes it from sibling tools like findPetsByStatus, findPetsByTags, and mutation tools, though it stops short of explaining any additional scope or response characteristics.

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 phrase 'by ID' implies the tool should be used when an agent already has a pet ID and needs the matching pet. However, it does not explicitly mention alternatives such as finding by status or tags, nor does it describe when not to use this tool.

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