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

Annotations already declare readOnlyHint=true, openWorldHint=true, and destructiveHint=false, so safety is covered. The description adds real value beyond those hints by disclosing a tiered response: basic fields on free plans, extended fields (height, weight, lifespan, traits, purpose) on paid plans, plus a 1-credit cost. It does not describe fuzzy or partial matching behavior for the name lookup, which is the main remaining gap.

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, front-loaded with the capability and followed by the plan-tier and cost caveats; every sentence earns its place. Minor redundancy in the leading "Dog Breeds: Dog Breeds searches" restatement of the title.

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 single-parameter read lookup with an output schema, the definition supplies what annotations and schema do not: the shape of the response across plan tiers and the credit cost. Nothing essential for correct invocation is missing, though a note on behavior for an unrecognized breed name would close the last gap.

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% and there is only one required parameter, so the schema already defines the breed input and gives an example. The description reinforces that lookup is by breed name, but adds no syntax, matching rules, or alias guidance beyond that. Baseline 3 applies.

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 uses a specific verb and resource ("searches canine breed records by name") and names the returned fields (official breed names, kennel club group classifications). It is easy to tell apart from the hundreds of siblings, but it does so only by subject matter, not by any explicit contrast with another tool.

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?

Usage is implied: call it with a breed name to look up breed data. The description adds a useful pricing constraint (1 credit) and a free-versus-paid data tier, but it gives no explicit when-to-use or when-not-to-use rule, because no sibling competes for the same task.

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