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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds value by enumerating the specific elements the tool returns (definition, formulas, coverage, limitations, discussion URL, snapshot metadata), which goes beyond the annotations. However, it does not describe any potential performance, caching, or edge-case behaviors, so a 3 is appropriate.

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, information-dense sentence with no fluff. It front-loads the primary purpose and lists all key deliverables in a compact list, making it easy to scan and understand.

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 tool with no parameters and no output schema, the description provides a solid overview of what the response contains. It covers definition, formulas, coverage, limitations, discussion URL, and metadata, which is comprehensive for a documentation/metadata endpoint. A small gap is that it does not describe the exact structure or format of the snapshot metadata, but this is not essential for selection or 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?

With zero parameters, the schema carries no information. The description compensates by clarifying what the tool actually provides, which aligns with the baseline score of 4 for parameter-free tools. It adds meaning by specifying the metric and the types of data returned.

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 a specific verb ('Get') and a specific resource: the definition, formulas, coverage, limitations, discussion URL, and snapshot metadata for AB5D's artist-level Oeuvre Total Days Held metric. It distinguishes itself from sibling tools like get_artist_otdh and list_artist_otdh, which presumably retrieve values rather than methodology.

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 does not explicitly state when to use this tool versus alternatives. It neither mentions conditions for selection nor names any sibling tools as alternatives. The usage context is only implied by the descriptor 'methodology' in the name and the listing of metadata elements.

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