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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and non-destructive behavior, so the description is not burdened with safety disclosure. It adds the useful context that qualifiers refine descriptors with an example, but does not describe edge cases such as descriptors with no qualifiers or retrieval limits. This is acceptable for a simple read-only lookup.

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 well-organized with a front-loaded main sentence followed by concise bullets. It is appropriately sized and avoids redundancy for the most part, though 'Understand aspects that can be specified' is somewhat vague and overlaps with the earlier bullet about finding qualifiers.

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-only lookup tool with an output schema and strong annotations, the description fully covers purpose, usage, and a concrete example. No critical information is missing for an agent to invoke this tool correctly.

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 description coverage is 100% and the single parameter mesh_id is already documented with a pattern and examples. The description reinforces the semantic relationship between descriptors and qualifiers via the 'Diabetes Mellitus/drug therapy' example, but does not add substantial parameter-level detail beyond the schema.

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 opens with a specific verb and resource: 'Get allowed qualifiers (subheadings) for a MeSH descriptor.' It clearly defines the tool's focus on qualifiers rather than descriptors themselves, distinguishing it from siblings like mesh_descriptor, mesh_search, and mesh_tree.

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 'Use this tool to' bullets provide clear context: finding combinable qualifiers, building precise search queries, and understanding specifiable aspects. It does not explicitly name alternatives or state when not to use it, but the intended use cases are concrete enough for an agent to pick this tool appropriately.

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