BSP key rates

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

Annotations only declare readOnlyHint and openWorldHint=false, but the description adds genuinely useful behavior: daily-fetch with cache serving, a per-row published_date that is explicitly NOT the fetch time, source_url linkage, and the null semantics of rate_percent (FX level and discontinued ON reference rate). This is exactly the kind of context annotations cannot carry.

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?

Front-loaded with the purpose, then supporting detail in descending priority, and the key routing hint is placed last. The field-by-field enumeration and parenthetical asides are somewhat dense, but each sentence carries real information rather than filler.

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 no-arg read tool with an output schema and safety annotations already present, the description covers caching cadence, date semantics, null handling, and sibling routing — nothing an agent needs to call it correctly is missing.

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?

There are zero parameters, so per the rubric the baseline is 4; there is nothing for the description to disambiguate. It does clarify return-field semantics instead, which is helpful but belongs more to output description.

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 ('Get the Bangko Sentral ng Pilipinas (BSP) Key Rates dashboard') and then enumerates exactly which rates it covers (target RRP, overnight lending/deposit facilities, BSP securities, TDF, inflation, USD/PHP). It explicitly distinguishes itself from the sibling get_bsp_policy_rate, so an agent can separate the two without opening either schema.

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?

Ends with an explicit alternative routing rule: 'For just the monetary-policy stance, use get_bsp_policy_rate instead.' That tells the agent both the broader use case here and the narrower sibling to prefer when only policy stance is needed, leaving nothing to inference.

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