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

Annotations already declare readOnly and idempotent, so the description needn't restate them; it adds useful behavior: substring matching, filter-only browsing, and a disclaiming caveat. It accurately aligns with idempotentHint=true.

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 compact and front-loaded: the operation and target come first, then the parameter-use rule, then the caveat. Every sentence earns its place without redundancy.

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 read-only search tool with four optional, fully documented parameters, the description covers what the tool does, how arguments combine, and what it returns. Without an output schema, a bit more detail on row contents would be nice, but it is still invocable 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 coverage is 100%, so the baseline is 3; the description adds extra semantic value by mapping the search dimensions to q, classification, and layer, and by explaining the q-or-filter browsing behavior. It doesn't provide new syntax details, but the schema already handles that.

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 identifies a specific verb ('Search'), resource ('RBI NBFC register'), and the match criteria (name/CIN substring, classification, layer). It distinguishes itself from sibling tools by focusing on the official register, though it does not explicitly name any alternative.

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?

Gives practical guidance: either q or a filter can be supplied, and a filter alone browses that slice, plus a caveat that registration doesn't imply creditworthiness. However, it doesn't describe when to choose this tool over sibling tools or when not to use it.

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