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

Annotations already declare readOnlyHint and no auth, but the description adds behavioral context beyond them: 'no auth', 'Percentages and index prices only; capital figures are never published', which constrains what data can be expected. It does not disclose ordering rules or any rate limits, keeping it from 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?

A single dense sentence, front-loaded with the resource and scope. Every clause (ranked list, fields, data limits, downstream symbols) earns its place, though the em-dash-heavy packing makes it slightly heavy to parse.

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 carries the return burden and does so by enumerating the returned fields and noting the symbols feed sibling tools. It omits ordering/pagination behavior, which would be needed for fully correct invocation.

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% with only 2 parameters, so the schema already documents both limit and status. The description restates the status values (live / paper / standing) but adds no syntax or semantics beyond what the schema provides; baseline 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 (list) and resource (Tuatara-managed funds) with enumerated return fields (name, sleeve, long/short, status, index price, % return). It explicitly names the siblings get_fund and get_fund_history whose take it feeds, so an agent can place it in the workflow without opening another 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?

The closing sentence routes the agent: this tool returns the symbols that get_fund and get_fund_history consume, strongly implying 'list first, then drill in'. However, it never states exclusions (e.g., when to prefer get_fund directly) or pagination/limit guidance, so it falls just short of explicit when-not guidance.

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