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

Annotations already declare readOnlyHint=true and openWorldHint=false, establishing the safety profile. The description adds valuable behavioral details: the scope of the search corpus, the exclusion of /notes, and the exact fields returned, which go beyond annotation info.

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 four concise sentences, each serving a distinct purpose: core functionality, output format, scope exclusion, and alternative guidance. It is front-loaded with the main verb and resource.

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 search tool with a simple parameter set and an output schema, the description covers all relevant context: what is searched, what is returned, what is excluded, and the best alternative. There are no significant gaps given the tool's simplicity.

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?

Both parameters have full descriptions in the input schema, giving 100% coverage. The tool description does not add any additional meaning for query or topK beyond what the schema already states, so the baseline of 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 the specific verb 'Semantic search' and names the exact corpus (Marcus Aurelius, Seneca, Epictetus), with clear output expectations. It also explicitly distinguishes from sibling get_entry, making its purpose unmistakable.

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?

It explicitly states when not to use the tool (thematic essays at /notes are not covered) and directs users to the alternative (get_entry) for exact citations. This provides clear decision criteria for tool selection.

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