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

Annotations already declare readOnlyHint=true and openWorldHint=false, which covers the safety profile. The description adds valuable operational context beyond this: daily updates, keyless access, historical depth to 1994, and the specific arXiv categories and momentum-scaling formula. It does not contradict the annotations and clarifies the tool's data source and update cadence.

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 three sentences and front-loaded with the return value, then usage context, then operational details. However, there is minor redundancy: 'Daily' appears twice ('Daily, keyless, history to 1994' and 'Updates: daily'). This small duplication slightly reduces conciseness.

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?

There is no output schema, so the description adequately explains return values: the 0-100 index, per-category counts, and 8 recent paper titles. It also covers update frequency, authentication, and historical depth. For a tool with one optional parameter and a read-only operation, the description is sufficiently complete for an agent to understand what it will receive.

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 for the single parameter 'days' is 100%, with a detailed description in the schema itself. The description adds only indirect hints ('history to 1994', 'Daily') that do not meaningfully go beyond the schema's explanation. With high schema coverage, the baseline of 3 is appropriate; the description does not provide additional parameter semantics.

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 what the tool does: 'Returns a 0-100 AI research velocity index' with specific details on the calculation (papers/day, 7d momentum) and output contents (per-category counts, 8 recent paper titles). The verb 'Returns' and specific resource 'AI research velocity index' make the purpose unmistakable, and this tool is distinct from siblings in its focus on arXiv AI/ML research pace.

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 provides explicit when-to-use guidance: 'Call when the user asks about AI/ML research pace, arXiv submission trends, or whether AI attention is accelerating, or when timing AI-sector launches, content, hiring, or allocation decisions.' It does not mention when not to use it or name alternatives, but the context is clear enough for an agent to select this tool appropriately.

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