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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint as safe. The description adds behavioral context about returning an array of bank entries and that no parameters are required, which is useful beyond the annotations.

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 mostly concise but contains a redundant fragment 'Malaysian financial institutions to Bank Negara Malaysia.' This adds no value and disrupts flow. The first two sentences are clear.

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?

Given no output schema, the description explains the return is an array of bank entries with current rate levels and lists three specific rates. However, it does not detail the fields within each entry, leaving some ambiguity about the data structure.

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 coverage is 100%. The description confirms no parameters are required, which is sufficient. Baseline for 0 params is 4.

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 it fetches the latest Base Rate, Base Lending Rate, and indicative effective lending rate for Malaysian financial institutions. The tool name and title align, and it is distinguishable from sibling tools like bnm_exchange_rates and bnm_policy_rate_opr.

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 implies use for retrieving Malaysian base rates but does not explicitly state when to use this tool versus alternatives like bnm_policy_rate_opr or bnm_exchange_rates. No exclusions or context about preconditions are provided.

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