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

With no annotations, the description carries the burden of behavioral disclosure. It provides valuable information about data freshness (metadata stable, prices updated as new source data arrives), which explains the update behavior. However, it does not disclose other behavioral traits such as authentication, rate limits, or the exact structure of the returned list (though output schema partially covers that).

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 concise and front-loaded with the primary purpose, followed by a separate sentence for data freshness. Every sentence adds value: the first defines the tool's function and scope, the second clarifies data volatility. No unnecessary words or repetition.

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 the tool's simplicity (zero parameters) and the presence of an output schema, the description is fairly complete. It provides the domain, scope, and data freshness expectations. It could be slightly richer by explicitly noting whether the list includes all benchmarks or what specific fields are returned, but the output schema likely covers those details, so this is adequate.

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?

The tool has zero parameters, so the description correctly includes no parameter details. The schema coverage is 100% (vacuously), and the description's mention of scope (benchmark assets for Bulgarian pensions) provides context for what the list contains, satisfying the baseline for zero-parameter tools.

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 uses a specific verb ('list') and resource ('benchmark assets') with a clear domain (Bulgarian pension comparisons). It adds context about including inflation and market references and specific fund types (UPF, PPF, VPF/DPF), which clarifies its scope. However, it does not explicitly distinguish itself from similar sibling tools like get_bulgarian_pension_benchmarks or get_benchmark_series.

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 usage by stating it lists benchmark assets and includes institutional fund types, but it does not explicitly state when to use this tool over its siblings or provide any exclusions/alternatives. The context of Bulgarian pension comparisons is useful but the guidance is not explicit.

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