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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so the safety profile is covered; the description adds genuinely new behavioral context by declaring that no pricing data is returned and specifying the return shape (a Markdown table of asset classes with tool, size and filters). It does not mention volume/pagination, but for a small static catalog that matters little.

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, followed by usage guidance and a short returns note; the parenthetical scope narrowing does real work. Minor waste in the Python-style 'str: Markdown table' return formatting, which could be a plain sentence.

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?

A zero-parameter, read-only discovery tool with no output schema; the description covers purpose, ordering relative to siblings, what the rows contain, and the return medium. Nothing an agent needs in order to call it correctly and interpret the result 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?

The tool takes zero parameters, so the baseline is 4 and there is nothing for the description to disambiguate. It correctly spends no space on arguments and instead explains what the parameterless result contains.

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 ('List the Finance Database's asset classes') and immediately narrows the scope with 'which instruments exist and how they are classified, no prices', plus names the row contents (tool, size, filters). This clearly separates it from siblings like equities, cryptos or search_instruments, which deal with actual instruments and prices.

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?

Explicitly prescribes ordering ('Use this first to see what is available'), explains that each asset class has its own tool whose filters are listed here, and routes filter-value lookups to `show_options`. That is concrete when-to-use and alternative-routing guidance rather than implied usage.

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