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

Annotations already declare read-only, idempotent, and non-destructive behavior. The description adds value by stating 'Zero cost' and 'Sourced from Flatscope's glossary', which clarifies it is a lookup with no side effects or charges. No contradictions with annotations.

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, both front-loaded with action and key details. No wasted words; every sentence contributes: the first defines purpose and examples, the second adds source and cost. Ideal for quick parsing.

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 simplicity of the tool (single string parameter, no output schema), the description is fully complete. It explains what the tool does, what terms are covered, the source, and cost. No need for return-value details since the output is self-explanatory.

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 the baseline is 3. The description adds meaning by specifying the domain ('UK leasehold or flat-buying term') and providing concrete examples, which helps the agent understand the expected input beyond the schema's generic description.

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 clearly states the action ('Return'), the resource ('plain-English definition'), and specifies the domain ('UK leasehold or flat-buying term') with relevant examples ('marriage value', 'Section 20'). It distinguishes itself from sibling tools like 'analyze_flat' and 'get_flat_analysis', which focus on property analysis rather than glossary lookup.

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 description implies usage when a definition is needed and notes the source ('Flatscope's glossary') and cost ('Zero cost'), but does not explicitly state when to use or avoid this tool relative to siblings. No exclusion criteria or alternatives are mentioned, though the context of sibling names suggests this is for term definitions.

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