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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world (openWorldHint=false). The description reinforces the closed corpus ('held in this dataset') and, unusually, discloses the returned fields (reference, date, summary, page and PDF links), which the annotations do not cover. Pagination and result-count behavior remain undisclosed, keeping it below a 5.

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 earning their place: the first front-loads the resource, scope and return shape, the second delivers the usage trigger. No filler or repetition of the title.

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?

With no output schema, the description compensates by enumerating the return fields, and both parameters are fully documented in the schema, so an agent can call this correctly. It could still say what happens with zero matches or how results are limited, and it does not route between the other search-family siblings.

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%: the query parameter's format and the full category enum-to-label mapping are already documented in the schema. The description only echoes that matching happens by topic, reference number or category, adding no syntax or constraint detail beyond the schema, so the baseline of 3 applies.

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?

States a specific verb and resource ('Finds the RBI Master Directions for ... NBFCs held in this dataset') plus the match dimensions (topic, reference number, category). It is distinguishable from sibling search/lookup tools such as search_bare_acts and lookup_bare_act_section, which target bare acts rather than the NBFC Master Directions corpus.

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 clear context for use ('Use for NBFC regulatory-compliance questions') with concrete examples of the topics covered (fair practices, KYC, provisioning, registration). It stops short of naming alternatives or when-not-to-use cases, so it falls just below the explicit routing bar.

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